1 /*
2 * jidctint.c
3 *
4 * Copyright (C) 1991-1998, Thomas G. Lane.
5 * Modification developed 2002-2009 by Guido Vollbeding.
6 * This file is part of the Independent JPEG Group's software.
7 * For conditions of distribution and use, see the accompanying README file.
8 *
9 * This file contains a slow-but-accurate integer implementation of the
10 * inverse DCT (Discrete Cosine Transform). In the IJG code, this routine
11 * must also perform dequantization of the input coefficients.
12 *
13 * A 2-D IDCT can be done by 1-D IDCT on each column followed by 1-D IDCT
14 * on each row (or vice versa, but it's more convenient to emit a row at
15 * a time). Direct algorithms are also available, but they are much more
16 * complex and seem not to be any faster when reduced to code.
17 *
18 * This implementation is based on an algorithm described in
19 * C. Loeffler, A. Ligtenberg and G. Moschytz, "Practical Fast 1-D DCT
20 * Algorithms with 11 Multiplications", Proc. Int'l. Conf. on Acoustics,
21 * Speech, and Signal Processing 1989 (ICASSP '89), pp. 988-991.
22 * The primary algorithm described there uses 11 multiplies and 29 adds.
23 * We use their alternate method with 12 multiplies and 32 adds.
24 * The advantage of this method is that no data path contains more than one
25 * multiplication; this allows a very simple and accurate implementation in
26 * scaled fixed-point arithmetic, with a minimal number of shifts.
27 *
28 * We also provide IDCT routines with various output sample block sizes for
29 * direct resolution reduction or enlargement and for direct resolving the
30 * common 2x1 and 1x2 subsampling cases without additional resampling: NxN
31 * (N=1...16), 2NxN, and Nx2N (N=1...8) pixels for one 8x8 input DCT block.
32 *
33 * For N<8 we simply take the corresponding low-frequency coefficients of
34 * the 8x8 input DCT block and apply an NxN point IDCT on the sub-block
35 * to yield the downscaled outputs.
36 * This can be seen as direct low-pass downsampling from the DCT domain
37 * point of view rather than the usual spatial domain point of view,
38 * yielding significant computational savings and results at least
39 * as good as common bilinear (averaging) spatial downsampling.
40 *
41 * For N>8 we apply a partial NxN IDCT on the 8 input coefficients as
42 * lower frequencies and higher frequencies assumed to be zero.
43 * It turns out that the computational effort is similar to the 8x8 IDCT
44 * regarding the output size.
45 * Furthermore, the scaling and descaling is the same for all IDCT sizes.
46 *
47 * CAUTION: We rely on the FIX() macro except for the N=1,2,4,8 cases
48 * since there would be too many additional constants to pre-calculate.
49 */
50
51 #define JPEG_INTERNALS
52 #include "jinclude.h"
53 #include "jpeglib.h"
54 #include "jdct.h" /* Private declarations for DCT subsystem */
55
56 #ifdef DCT_ISLOW_SUPPORTED
57
58
59 /*
60 * This module is specialized to the case DCTSIZE = 8.
61 */
62
63 #if DCTSIZE != 8
64 Sorry, this code only copes with 8x8 DCT blocks. /* deliberate syntax err */
65 #endif
66
67
68 /*
69 * The poop on this scaling stuff is as follows:
70 *
71 * Each 1-D IDCT step produces outputs which are a factor of sqrt(N)
72 * larger than the true IDCT outputs. The final outputs are therefore
73 * a factor of N larger than desired; since N=8 this can be cured by
74 * a simple right shift at the end of the algorithm. The advantage of
75 * this arrangement is that we save two multiplications per 1-D IDCT,
76 * because the y0 and y4 inputs need not be divided by sqrt(N).
77 *
78 * We have to do addition and subtraction of the integer inputs, which
79 * is no problem, and multiplication by fractional constants, which is
80 * a problem to do in integer arithmetic. We multiply all the constants
81 * by CONST_SCALE and convert them to integer constants (thus retaining
82 * CONST_BITS bits of precision in the constants). After doing a
83 * multiplication we have to divide the product by CONST_SCALE, with proper
84 * rounding, to produce the correct output. This division can be done
85 * cheaply as a right shift of CONST_BITS bits. We postpone shifting
86 * as long as possible so that partial sums can be added together with
87 * full fractional precision.
88 *
89 * The outputs of the first pass are scaled up by PASS1_BITS bits so that
90 * they are represented to better-than-integral precision. These outputs
91 * require BITS_IN_JSAMPLE + PASS1_BITS + 3 bits; this fits in a 16-bit word
92 * with the recommended scaling. (To scale up 12-bit sample data further, an
93 * intermediate INT32 array would be needed.)
94 *
95 * To avoid overflow of the 32-bit intermediate results in pass 2, we must
96 * have BITS_IN_JSAMPLE + CONST_BITS + PASS1_BITS <= 26. Error analysis
97 * shows that the values given below are the most effective.
98 */
99
100 #if BITS_IN_JSAMPLE == 8
101 #define CONST_BITS 13
102 #define PASS1_BITS 2
103 #else
104 #define CONST_BITS 13
105 #define PASS1_BITS 1 /* lose a little precision to avoid overflow */
106 #endif
107
108 /* Some C compilers fail to reduce "FIX(constant)" at compile time, thus
109 * causing a lot of useless floating-point operations at run time.
110 * To get around this we use the following pre-calculated constants.
111 * If you change CONST_BITS you may want to add appropriate values.
112 * (With a reasonable C compiler, you can just rely on the FIX() macro...)
113 */
114
115 #if CONST_BITS == 13
116 #define FIX_0_298631336 ((INT32) 2446) /* FIX(0.298631336) */
117 #define FIX_0_390180644 ((INT32) 3196) /* FIX(0.390180644) */
118 #define FIX_0_541196100 ((INT32) 4433) /* FIX(0.541196100) */
119 #define FIX_0_765366865 ((INT32) 6270) /* FIX(0.765366865) */
120 #define FIX_0_899976223 ((INT32) 7373) /* FIX(0.899976223) */
121 #define FIX_1_175875602 ((INT32) 9633) /* FIX(1.175875602) */
122 #define FIX_1_501321110 ((INT32) 12299) /* FIX(1.501321110) */
123 #define FIX_1_847759065 ((INT32) 15137) /* FIX(1.847759065) */
124 #define FIX_1_961570560 ((INT32) 16069) /* FIX(1.961570560) */
125 #define FIX_2_053119869 ((INT32) 16819) /* FIX(2.053119869) */
126 #define FIX_2_562915447 ((INT32) 20995) /* FIX(2.562915447) */
127 #define FIX_3_072711026 ((INT32) 25172) /* FIX(3.072711026) */
128 #else
129 #define FIX_0_298631336 FIX(0.298631336)
130 #define FIX_0_390180644 FIX(0.390180644)
131 #define FIX_0_541196100 FIX(0.541196100)
132 #define FIX_0_765366865 FIX(0.765366865)
133 #define FIX_0_899976223 FIX(0.899976223)
134 #define FIX_1_175875602 FIX(1.175875602)
135 #define FIX_1_501321110 FIX(1.501321110)
136 #define FIX_1_847759065 FIX(1.847759065)
137 #define FIX_1_961570560 FIX(1.961570560)
138 #define FIX_2_053119869 FIX(2.053119869)
139 #define FIX_2_562915447 FIX(2.562915447)
140 #define FIX_3_072711026 FIX(3.072711026)
141 #endif
142
143
144 /* Multiply an INT32 variable by an INT32 constant to yield an INT32 result.
145 * For 8-bit samples with the recommended scaling, all the variable
146 * and constant values involved are no more than 16 bits wide, so a
147 * 16x16->32 bit multiply can be used instead of a full 32x32 multiply.
148 * For 12-bit samples, a full 32-bit multiplication will be needed.
149 */
150
151 #if BITS_IN_JSAMPLE == 8
152 #define MULTIPLY(var,const) MULTIPLY16C16(var,const)
153 #else
154 #define MULTIPLY(var,const) ((var) * (const))
155 #endif
156
157
158 /* Dequantize a coefficient by multiplying it by the multiplier-table
159 * entry; produce an int result. In this module, both inputs and result
160 * are 16 bits or less, so either int or short multiply will work.
161 */
162
163 #define DEQUANTIZE(coef,quantval) (((ISLOW_MULT_TYPE) (coef)) * (quantval))
164
165
166 /*
167 * Perform dequantization and inverse DCT on one block of coefficients.
168 */
169
170 GLOBAL(void)
171 jpeg_idct_islow (j_decompress_ptr cinfo, jpeg_component_info * compptr,
172 JCOEFPTR coef_block,
173 JSAMPARRAY output_buf, JDIMENSION output_col)
174 {
175 INT32 tmp0, tmp1, tmp2, tmp3;
176 INT32 tmp10, tmp11, tmp12, tmp13;
177 INT32 z1, z2, z3;
178 JCOEFPTR inptr;
179 ISLOW_MULT_TYPE * quantptr;
180 int * wsptr;
181 JSAMPROW outptr;
182 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
183 int ctr;
184 int workspace[DCTSIZE2]; /* buffers data between passes */
185 SHIFT_TEMPS
186
187 /* Pass 1: process columns from input, store into work array. */
188 /* Note results are scaled up by sqrt(8) compared to a true IDCT; */
189 /* furthermore, we scale the results by 2**PASS1_BITS. */
190
191 inptr = coef_block;
192 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
193 wsptr = workspace;
194 for (ctr = DCTSIZE; ctr > 0; ctr--) {
195 /* Due to quantization, we will usually find that many of the input
196 * coefficients are zero, especially the AC terms. We can exploit this
197 * by short-circuiting the IDCT calculation for any column in which all
198 * the AC terms are zero. In that case each output is equal to the
199 * DC coefficient (with scale factor as needed).
200 * With typical images and quantization tables, half or more of the
201 * column DCT calculations can be simplified this way.
202 */
203
204 if (inptr[DCTSIZE*1] == 0 && inptr[DCTSIZE*2] == 0 &&
205 inptr[DCTSIZE*3] == 0 && inptr[DCTSIZE*4] == 0 &&
206 inptr[DCTSIZE*5] == 0 && inptr[DCTSIZE*6] == 0 &&
207 inptr[DCTSIZE*7] == 0) {
208 /* AC terms all zero */
209 int dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]) << PASS1_BITS;
210
211 wsptr[DCTSIZE*0] = dcval;
212 wsptr[DCTSIZE*1] = dcval;
213 wsptr[DCTSIZE*2] = dcval;
214 wsptr[DCTSIZE*3] = dcval;
215 wsptr[DCTSIZE*4] = dcval;
216 wsptr[DCTSIZE*5] = dcval;
217 wsptr[DCTSIZE*6] = dcval;
218 wsptr[DCTSIZE*7] = dcval;
219
220 inptr++; /* advance pointers to next column */
221 quantptr++;
222 wsptr++;
223 continue;
224 }
225
226 /* Even part: reverse the even part of the forward DCT. */
227 /* The rotator is sqrt(2)*c(-6). */
228
229 z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
230 z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
231
232 z1 = MULTIPLY(z2 + z3, FIX_0_541196100);
233 tmp2 = z1 + MULTIPLY(z2, FIX_0_765366865);
234 tmp3 = z1 - MULTIPLY(z3, FIX_1_847759065);
235
236 z2 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
237 z3 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
238 z2 <<= CONST_BITS;
239 z3 <<= CONST_BITS;
240 /* Add fudge factor here for final descale. */
241 z2 += ONE << (CONST_BITS-PASS1_BITS-1);
242
243 tmp0 = z2 + z3;
244 tmp1 = z2 - z3;
245
246 tmp10 = tmp0 + tmp2;
247 tmp13 = tmp0 - tmp2;
248 tmp11 = tmp1 + tmp3;
249 tmp12 = tmp1 - tmp3;
250
251 /* Odd part per figure 8; the matrix is unitary and hence its
252 * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively.
253 */
254
255 tmp0 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
256 tmp1 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
257 tmp2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
258 tmp3 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
259
260 z2 = tmp0 + tmp2;
261 z3 = tmp1 + tmp3;
262
263 z1 = MULTIPLY(z2 + z3, FIX_1_175875602); /* sqrt(2) * c3 */
264 z2 = MULTIPLY(z2, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
265 z3 = MULTIPLY(z3, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
266 z2 += z1;
267 z3 += z1;
268
269 z1 = MULTIPLY(tmp0 + tmp3, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */
270 tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
271 tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */
272 tmp0 += z1 + z2;
273 tmp3 += z1 + z3;
274
275 z1 = MULTIPLY(tmp1 + tmp2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
276 tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
277 tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
278 tmp1 += z1 + z3;
279 tmp2 += z1 + z2;
280
281 /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */
282
283 wsptr[DCTSIZE*0] = (int) RIGHT_SHIFT(tmp10 + tmp3, CONST_BITS-PASS1_BITS);
284 wsptr[DCTSIZE*7] = (int) RIGHT_SHIFT(tmp10 - tmp3, CONST_BITS-PASS1_BITS);
285 wsptr[DCTSIZE*1] = (int) RIGHT_SHIFT(tmp11 + tmp2, CONST_BITS-PASS1_BITS);
286 wsptr[DCTSIZE*6] = (int) RIGHT_SHIFT(tmp11 - tmp2, CONST_BITS-PASS1_BITS);
287 wsptr[DCTSIZE*2] = (int) RIGHT_SHIFT(tmp12 + tmp1, CONST_BITS-PASS1_BITS);
288 wsptr[DCTSIZE*5] = (int) RIGHT_SHIFT(tmp12 - tmp1, CONST_BITS-PASS1_BITS);
289 wsptr[DCTSIZE*3] = (int) RIGHT_SHIFT(tmp13 + tmp0, CONST_BITS-PASS1_BITS);
290 wsptr[DCTSIZE*4] = (int) RIGHT_SHIFT(tmp13 - tmp0, CONST_BITS-PASS1_BITS);
291
292 inptr++; /* advance pointers to next column */
293 quantptr++;
294 wsptr++;
295 }
296
297 /* Pass 2: process rows from work array, store into output array. */
298 /* Note that we must descale the results by a factor of 8 == 2**3, */
299 /* and also undo the PASS1_BITS scaling. */
300
301 wsptr = workspace;
302 for (ctr = 0; ctr < DCTSIZE; ctr++) {
303 outptr = output_buf[ctr] + output_col;
304 /* Rows of zeroes can be exploited in the same way as we did with columns.
305 * However, the column calculation has created many nonzero AC terms, so
306 * the simplification applies less often (typically 5% to 10% of the time).
307 * On machines with very fast multiplication, it's possible that the
308 * test takes more time than it's worth. In that case this section
309 * may be commented out.
310 */
311
312 #ifndef NO_ZERO_ROW_TEST
313 if (wsptr[1] == 0 && wsptr[2] == 0 && wsptr[3] == 0 && wsptr[4] == 0 &&
314 wsptr[5] == 0 && wsptr[6] == 0 && wsptr[7] == 0) {
315 /* AC terms all zero */
316 JSAMPLE dcval = range_limit[(int) DESCALE((INT32) wsptr[0], PASS1_BITS+3)
317 & RANGE_MASK];
318
319 outptr[0] = dcval;
320 outptr[1] = dcval;
321 outptr[2] = dcval;
322 outptr[3] = dcval;
323 outptr[4] = dcval;
324 outptr[5] = dcval;
325 outptr[6] = dcval;
326 outptr[7] = dcval;
327
328 wsptr += DCTSIZE; /* advance pointer to next row */
329 continue;
330 }
331 #endif
332
333 /* Even part: reverse the even part of the forward DCT. */
334 /* The rotator is sqrt(2)*c(-6). */
335
336 z2 = (INT32) wsptr[2];
337 z3 = (INT32) wsptr[6];
338
339 z1 = MULTIPLY(z2 + z3, FIX_0_541196100);
340 tmp2 = z1 + MULTIPLY(z2, FIX_0_765366865);
341 tmp3 = z1 - MULTIPLY(z3, FIX_1_847759065);
342
343 /* Add fudge factor here for final descale. */
344 z2 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
345 z3 = (INT32) wsptr[4];
346
347 tmp0 = (z2 + z3) << CONST_BITS;
348 tmp1 = (z2 - z3) << CONST_BITS;
349
350 tmp10 = tmp0 + tmp2;
351 tmp13 = tmp0 - tmp2;
352 tmp11 = tmp1 + tmp3;
353 tmp12 = tmp1 - tmp3;
354
355 /* Odd part per figure 8; the matrix is unitary and hence its
356 * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively.
357 */
358
359 tmp0 = (INT32) wsptr[7];
360 tmp1 = (INT32) wsptr[5];
361 tmp2 = (INT32) wsptr[3];
362 tmp3 = (INT32) wsptr[1];
363
364 z2 = tmp0 + tmp2;
365 z3 = tmp1 + tmp3;
366
367 z1 = MULTIPLY(z2 + z3, FIX_1_175875602); /* sqrt(2) * c3 */
368 z2 = MULTIPLY(z2, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
369 z3 = MULTIPLY(z3, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
370 z2 += z1;
371 z3 += z1;
372
373 z1 = MULTIPLY(tmp0 + tmp3, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */
374 tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
375 tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */
376 tmp0 += z1 + z2;
377 tmp3 += z1 + z3;
378
379 z1 = MULTIPLY(tmp1 + tmp2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
380 tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
381 tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
382 tmp1 += z1 + z3;
383 tmp2 += z1 + z2;
384
385 /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */
386
387 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp3,
388 CONST_BITS+PASS1_BITS+3)
389 & RANGE_MASK];
390 outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp3,
391 CONST_BITS+PASS1_BITS+3)
392 & RANGE_MASK];
393 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp2,
394 CONST_BITS+PASS1_BITS+3)
395 & RANGE_MASK];
396 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp2,
397 CONST_BITS+PASS1_BITS+3)
398 & RANGE_MASK];
399 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp1,
400 CONST_BITS+PASS1_BITS+3)
401 & RANGE_MASK];
402 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp1,
403 CONST_BITS+PASS1_BITS+3)
404 & RANGE_MASK];
405 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp13 + tmp0,
406 CONST_BITS+PASS1_BITS+3)
407 & RANGE_MASK];
408 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp13 - tmp0,
409 CONST_BITS+PASS1_BITS+3)
410 & RANGE_MASK];
411
412 wsptr += DCTSIZE; /* advance pointer to next row */
413 }
414 }
415
416 #ifdef IDCT_SCALING_SUPPORTED
417
418
419 /*
420 * Perform dequantization and inverse DCT on one block of coefficients,
421 * producing a 7x7 output block.
422 *
423 * Optimized algorithm with 12 multiplications in the 1-D kernel.
424 * cK represents sqrt(2) * cos(K*pi/14).
425 */
426
427 GLOBAL(void)
428 jpeg_idct_7x7 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
429 JCOEFPTR coef_block,
430 JSAMPARRAY output_buf, JDIMENSION output_col)
431 {
432 INT32 tmp0, tmp1, tmp2, tmp10, tmp11, tmp12, tmp13;
433 INT32 z1, z2, z3;
434 JCOEFPTR inptr;
435 ISLOW_MULT_TYPE * quantptr;
436 int * wsptr;
437 JSAMPROW outptr;
438 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
439 int ctr;
440 int workspace[7*7]; /* buffers data between passes */
441 SHIFT_TEMPS
442
443 /* Pass 1: process columns from input, store into work array. */
444
445 inptr = coef_block;
446 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
447 wsptr = workspace;
448 for (ctr = 0; ctr < 7; ctr++, inptr++, quantptr++, wsptr++) {
449 /* Even part */
450
451 tmp13 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
452 tmp13 <<= CONST_BITS;
453 /* Add fudge factor here for final descale. */
454 tmp13 += ONE << (CONST_BITS-PASS1_BITS-1);
455
456 z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
457 z2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
458 z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
459
460 tmp10 = MULTIPLY(z2 - z3, FIX(0.881747734)); /* c4 */
461 tmp12 = MULTIPLY(z1 - z2, FIX(0.314692123)); /* c6 */
462 tmp11 = tmp10 + tmp12 + tmp13 - MULTIPLY(z2, FIX(1.841218003)); /* c2+c4-c6 */
463 tmp0 = z1 + z3;
464 z2 -= tmp0;
465 tmp0 = MULTIPLY(tmp0, FIX(1.274162392)) + tmp13; /* c2 */
466 tmp10 += tmp0 - MULTIPLY(z3, FIX(0.077722536)); /* c2-c4-c6 */
467 tmp12 += tmp0 - MULTIPLY(z1, FIX(2.470602249)); /* c2+c4+c6 */
468 tmp13 += MULTIPLY(z2, FIX(1.414213562)); /* c0 */
469
470 /* Odd part */
471
472 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
473 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
474 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
475
476 tmp1 = MULTIPLY(z1 + z2, FIX(0.935414347)); /* (c3+c1-c5)/2 */
477 tmp2 = MULTIPLY(z1 - z2, FIX(0.170262339)); /* (c3+c5-c1)/2 */
478 tmp0 = tmp1 - tmp2;
479 tmp1 += tmp2;
480 tmp2 = MULTIPLY(z2 + z3, - FIX(1.378756276)); /* -c1 */
481 tmp1 += tmp2;
482 z2 = MULTIPLY(z1 + z3, FIX(0.613604268)); /* c5 */
483 tmp0 += z2;
484 tmp2 += z2 + MULTIPLY(z3, FIX(1.870828693)); /* c3+c1-c5 */
485
486 /* Final output stage */
487
488 wsptr[7*0] = (int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS-PASS1_BITS);
489 wsptr[7*6] = (int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS-PASS1_BITS);
490 wsptr[7*1] = (int) RIGHT_SHIFT(tmp11 + tmp1, CONST_BITS-PASS1_BITS);
491 wsptr[7*5] = (int) RIGHT_SHIFT(tmp11 - tmp1, CONST_BITS-PASS1_BITS);
492 wsptr[7*2] = (int) RIGHT_SHIFT(tmp12 + tmp2, CONST_BITS-PASS1_BITS);
493 wsptr[7*4] = (int) RIGHT_SHIFT(tmp12 - tmp2, CONST_BITS-PASS1_BITS);
494 wsptr[7*3] = (int) RIGHT_SHIFT(tmp13, CONST_BITS-PASS1_BITS);
495 }
496
497 /* Pass 2: process 7 rows from work array, store into output array. */
498
499 wsptr = workspace;
500 for (ctr = 0; ctr < 7; ctr++) {
501 outptr = output_buf[ctr] + output_col;
502
503 /* Even part */
504
505 /* Add fudge factor here for final descale. */
506 tmp13 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
507 tmp13 <<= CONST_BITS;
508
509 z1 = (INT32) wsptr[2];
510 z2 = (INT32) wsptr[4];
511 z3 = (INT32) wsptr[6];
512
513 tmp10 = MULTIPLY(z2 - z3, FIX(0.881747734)); /* c4 */
514 tmp12 = MULTIPLY(z1 - z2, FIX(0.314692123)); /* c6 */
515 tmp11 = tmp10 + tmp12 + tmp13 - MULTIPLY(z2, FIX(1.841218003)); /* c2+c4-c6 */
516 tmp0 = z1 + z3;
517 z2 -= tmp0;
518 tmp0 = MULTIPLY(tmp0, FIX(1.274162392)) + tmp13; /* c2 */
519 tmp10 += tmp0 - MULTIPLY(z3, FIX(0.077722536)); /* c2-c4-c6 */
520 tmp12 += tmp0 - MULTIPLY(z1, FIX(2.470602249)); /* c2+c4+c6 */
521 tmp13 += MULTIPLY(z2, FIX(1.414213562)); /* c0 */
522
523 /* Odd part */
524
525 z1 = (INT32) wsptr[1];
526 z2 = (INT32) wsptr[3];
527 z3 = (INT32) wsptr[5];
528
529 tmp1 = MULTIPLY(z1 + z2, FIX(0.935414347)); /* (c3+c1-c5)/2 */
530 tmp2 = MULTIPLY(z1 - z2, FIX(0.170262339)); /* (c3+c5-c1)/2 */
531 tmp0 = tmp1 - tmp2;
532 tmp1 += tmp2;
533 tmp2 = MULTIPLY(z2 + z3, - FIX(1.378756276)); /* -c1 */
534 tmp1 += tmp2;
535 z2 = MULTIPLY(z1 + z3, FIX(0.613604268)); /* c5 */
536 tmp0 += z2;
537 tmp2 += z2 + MULTIPLY(z3, FIX(1.870828693)); /* c3+c1-c5 */
538
539 /* Final output stage */
540
541 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
542 CONST_BITS+PASS1_BITS+3)
543 & RANGE_MASK];
544 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
545 CONST_BITS+PASS1_BITS+3)
546 & RANGE_MASK];
547 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp1,
548 CONST_BITS+PASS1_BITS+3)
549 & RANGE_MASK];
550 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp1,
551 CONST_BITS+PASS1_BITS+3)
552 & RANGE_MASK];
553 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp2,
554 CONST_BITS+PASS1_BITS+3)
555 & RANGE_MASK];
556 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp2,
557 CONST_BITS+PASS1_BITS+3)
558 & RANGE_MASK];
559 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp13,
560 CONST_BITS+PASS1_BITS+3)
561 & RANGE_MASK];
562
563 wsptr += 7; /* advance pointer to next row */
564 }
565 }
566
567
568 /*
569 * Perform dequantization and inverse DCT on one block of coefficients,
570 * producing a reduced-size 6x6 output block.
571 *
572 * Optimized algorithm with 3 multiplications in the 1-D kernel.
573 * cK represents sqrt(2) * cos(K*pi/12).
574 */
575
576 GLOBAL(void)
577 jpeg_idct_6x6 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
578 JCOEFPTR coef_block,
579 JSAMPARRAY output_buf, JDIMENSION output_col)
580 {
581 INT32 tmp0, tmp1, tmp2, tmp10, tmp11, tmp12;
582 INT32 z1, z2, z3;
583 JCOEFPTR inptr;
584 ISLOW_MULT_TYPE * quantptr;
585 int * wsptr;
586 JSAMPROW outptr;
587 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
588 int ctr;
589 int workspace[6*6]; /* buffers data between passes */
590 SHIFT_TEMPS
591
592 /* Pass 1: process columns from input, store into work array. */
593
594 inptr = coef_block;
595 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
596 wsptr = workspace;
597 for (ctr = 0; ctr < 6; ctr++, inptr++, quantptr++, wsptr++) {
598 /* Even part */
599
600 tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
601 tmp0 <<= CONST_BITS;
602 /* Add fudge factor here for final descale. */
603 tmp0 += ONE << (CONST_BITS-PASS1_BITS-1);
604 tmp2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
605 tmp10 = MULTIPLY(tmp2, FIX(0.707106781)); /* c4 */
606 tmp1 = tmp0 + tmp10;
607 tmp11 = RIGHT_SHIFT(tmp0 - tmp10 - tmp10, CONST_BITS-PASS1_BITS);
608 tmp10 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
609 tmp0 = MULTIPLY(tmp10, FIX(1.224744871)); /* c2 */
610 tmp10 = tmp1 + tmp0;
611 tmp12 = tmp1 - tmp0;
612
613 /* Odd part */
614
615 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
616 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
617 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
618 tmp1 = MULTIPLY(z1 + z3, FIX(0.366025404)); /* c5 */
619 tmp0 = tmp1 + ((z1 + z2) << CONST_BITS);
620 tmp2 = tmp1 + ((z3 - z2) << CONST_BITS);
621 tmp1 = (z1 - z2 - z3) << PASS1_BITS;
622
623 /* Final output stage */
624
625 wsptr[6*0] = (int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS-PASS1_BITS);
626 wsptr[6*5] = (int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS-PASS1_BITS);
627 wsptr[6*1] = (int) (tmp11 + tmp1);
628 wsptr[6*4] = (int) (tmp11 - tmp1);
629 wsptr[6*2] = (int) RIGHT_SHIFT(tmp12 + tmp2, CONST_BITS-PASS1_BITS);
630 wsptr[6*3] = (int) RIGHT_SHIFT(tmp12 - tmp2, CONST_BITS-PASS1_BITS);
631 }
632
633 /* Pass 2: process 6 rows from work array, store into output array. */
634
635 wsptr = workspace;
636 for (ctr = 0; ctr < 6; ctr++) {
637 outptr = output_buf[ctr] + output_col;
638
639 /* Even part */
640
641 /* Add fudge factor here for final descale. */
642 tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
643 tmp0 <<= CONST_BITS;
644 tmp2 = (INT32) wsptr[4];
645 tmp10 = MULTIPLY(tmp2, FIX(0.707106781)); /* c4 */
646 tmp1 = tmp0 + tmp10;
647 tmp11 = tmp0 - tmp10 - tmp10;
648 tmp10 = (INT32) wsptr[2];
649 tmp0 = MULTIPLY(tmp10, FIX(1.224744871)); /* c2 */
650 tmp10 = tmp1 + tmp0;
651 tmp12 = tmp1 - tmp0;
652
653 /* Odd part */
654
655 z1 = (INT32) wsptr[1];
656 z2 = (INT32) wsptr[3];
657 z3 = (INT32) wsptr[5];
658 tmp1 = MULTIPLY(z1 + z3, FIX(0.366025404)); /* c5 */
659 tmp0 = tmp1 + ((z1 + z2) << CONST_BITS);
660 tmp2 = tmp1 + ((z3 - z2) << CONST_BITS);
661 tmp1 = (z1 - z2 - z3) << CONST_BITS;
662
663 /* Final output stage */
664
665 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
666 CONST_BITS+PASS1_BITS+3)
667 & RANGE_MASK];
668 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
669 CONST_BITS+PASS1_BITS+3)
670 & RANGE_MASK];
671 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp1,
672 CONST_BITS+PASS1_BITS+3)
673 & RANGE_MASK];
674 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp1,
675 CONST_BITS+PASS1_BITS+3)
676 & RANGE_MASK];
677 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp2,
678 CONST_BITS+PASS1_BITS+3)
679 & RANGE_MASK];
680 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp2,
681 CONST_BITS+PASS1_BITS+3)
682 & RANGE_MASK];
683
684 wsptr += 6; /* advance pointer to next row */
685 }
686 }
687
688
689 /*
690 * Perform dequantization and inverse DCT on one block of coefficients,
691 * producing a reduced-size 5x5 output block.
692 *
693 * Optimized algorithm with 5 multiplications in the 1-D kernel.
694 * cK represents sqrt(2) * cos(K*pi/10).
695 */
696
697 GLOBAL(void)
698 jpeg_idct_5x5 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
699 JCOEFPTR coef_block,
700 JSAMPARRAY output_buf, JDIMENSION output_col)
701 {
702 INT32 tmp0, tmp1, tmp10, tmp11, tmp12;
703 INT32 z1, z2, z3;
704 JCOEFPTR inptr;
705 ISLOW_MULT_TYPE * quantptr;
706 int * wsptr;
707 JSAMPROW outptr;
708 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
709 int ctr;
710 int workspace[5*5]; /* buffers data between passes */
711 SHIFT_TEMPS
712
713 /* Pass 1: process columns from input, store into work array. */
714
715 inptr = coef_block;
716 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
717 wsptr = workspace;
718 for (ctr = 0; ctr < 5; ctr++, inptr++, quantptr++, wsptr++) {
719 /* Even part */
720
721 tmp12 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
722 tmp12 <<= CONST_BITS;
723 /* Add fudge factor here for final descale. */
724 tmp12 += ONE << (CONST_BITS-PASS1_BITS-1);
725 tmp0 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
726 tmp1 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
727 z1 = MULTIPLY(tmp0 + tmp1, FIX(0.790569415)); /* (c2+c4)/2 */
728 z2 = MULTIPLY(tmp0 - tmp1, FIX(0.353553391)); /* (c2-c4)/2 */
729 z3 = tmp12 + z2;
730 tmp10 = z3 + z1;
731 tmp11 = z3 - z1;
732 tmp12 -= z2 << 2;
733
734 /* Odd part */
735
736 z2 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
737 z3 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
738
739 z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c3 */
740 tmp0 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c1-c3 */
741 tmp1 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c1+c3 */
742
743 /* Final output stage */
744
745 wsptr[5*0] = (int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS-PASS1_BITS);
746 wsptr[5*4] = (int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS-PASS1_BITS);
747 wsptr[5*1] = (int) RIGHT_SHIFT(tmp11 + tmp1, CONST_BITS-PASS1_BITS);
748 wsptr[5*3] = (int) RIGHT_SHIFT(tmp11 - tmp1, CONST_BITS-PASS1_BITS);
749 wsptr[5*2] = (int) RIGHT_SHIFT(tmp12, CONST_BITS-PASS1_BITS);
750 }
751
752 /* Pass 2: process 5 rows from work array, store into output array. */
753
754 wsptr = workspace;
755 for (ctr = 0; ctr < 5; ctr++) {
756 outptr = output_buf[ctr] + output_col;
757
758 /* Even part */
759
760 /* Add fudge factor here for final descale. */
761 tmp12 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
762 tmp12 <<= CONST_BITS;
763 tmp0 = (INT32) wsptr[2];
764 tmp1 = (INT32) wsptr[4];
765 z1 = MULTIPLY(tmp0 + tmp1, FIX(0.790569415)); /* (c2+c4)/2 */
766 z2 = MULTIPLY(tmp0 - tmp1, FIX(0.353553391)); /* (c2-c4)/2 */
767 z3 = tmp12 + z2;
768 tmp10 = z3 + z1;
769 tmp11 = z3 - z1;
770 tmp12 -= z2 << 2;
771
772 /* Odd part */
773
774 z2 = (INT32) wsptr[1];
775 z3 = (INT32) wsptr[3];
776
777 z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c3 */
778 tmp0 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c1-c3 */
779 tmp1 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c1+c3 */
780
781 /* Final output stage */
782
783 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
784 CONST_BITS+PASS1_BITS+3)
785 & RANGE_MASK];
786 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
787 CONST_BITS+PASS1_BITS+3)
788 & RANGE_MASK];
789 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp1,
790 CONST_BITS+PASS1_BITS+3)
791 & RANGE_MASK];
792 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp1,
793 CONST_BITS+PASS1_BITS+3)
794 & RANGE_MASK];
795 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12,
796 CONST_BITS+PASS1_BITS+3)
797 & RANGE_MASK];
798
799 wsptr += 5; /* advance pointer to next row */
800 }
801 }
802
803
804 /*
805 * Perform dequantization and inverse DCT on one block of coefficients,
806 * producing a reduced-size 4x4 output block.
807 *
808 * Optimized algorithm with 3 multiplications in the 1-D kernel.
809 * cK represents sqrt(2) * cos(K*pi/16) [refers to 8-point IDCT].
810 */
811
812 GLOBAL(void)
813 jpeg_idct_4x4 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
814 JCOEFPTR coef_block,
815 JSAMPARRAY output_buf, JDIMENSION output_col)
816 {
817 INT32 tmp0, tmp2, tmp10, tmp12;
818 INT32 z1, z2, z3;
819 JCOEFPTR inptr;
820 ISLOW_MULT_TYPE * quantptr;
821 int * wsptr;
822 JSAMPROW outptr;
823 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
824 int ctr;
825 int workspace[4*4]; /* buffers data between passes */
826 SHIFT_TEMPS
827
828 /* Pass 1: process columns from input, store into work array. */
829
830 inptr = coef_block;
831 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
832 wsptr = workspace;
833 for (ctr = 0; ctr < 4; ctr++, inptr++, quantptr++, wsptr++) {
834 /* Even part */
835
836 tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
837 tmp2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
838
839 tmp10 = (tmp0 + tmp2) << PASS1_BITS;
840 tmp12 = (tmp0 - tmp2) << PASS1_BITS;
841
842 /* Odd part */
843 /* Same rotation as in the even part of the 8x8 LL&M IDCT */
844
845 z2 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
846 z3 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
847
848 z1 = MULTIPLY(z2 + z3, FIX_0_541196100); /* c6 */
849 /* Add fudge factor here for final descale. */
850 z1 += ONE << (CONST_BITS-PASS1_BITS-1);
851 tmp0 = RIGHT_SHIFT(z1 + MULTIPLY(z2, FIX_0_765366865), /* c2-c6 */
852 CONST_BITS-PASS1_BITS);
853 tmp2 = RIGHT_SHIFT(z1 - MULTIPLY(z3, FIX_1_847759065), /* c2+c6 */
854 CONST_BITS-PASS1_BITS);
855
856 /* Final output stage */
857
858 wsptr[4*0] = (int) (tmp10 + tmp0);
859 wsptr[4*3] = (int) (tmp10 - tmp0);
860 wsptr[4*1] = (int) (tmp12 + tmp2);
861 wsptr[4*2] = (int) (tmp12 - tmp2);
862 }
863
864 /* Pass 2: process 4 rows from work array, store into output array. */
865
866 wsptr = workspace;
867 for (ctr = 0; ctr < 4; ctr++) {
868 outptr = output_buf[ctr] + output_col;
869
870 /* Even part */
871
872 /* Add fudge factor here for final descale. */
873 tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
874 tmp2 = (INT32) wsptr[2];
875
876 tmp10 = (tmp0 + tmp2) << CONST_BITS;
877 tmp12 = (tmp0 - tmp2) << CONST_BITS;
878
879 /* Odd part */
880 /* Same rotation as in the even part of the 8x8 LL&M IDCT */
881
882 z2 = (INT32) wsptr[1];
883 z3 = (INT32) wsptr[3];
884
885 z1 = MULTIPLY(z2 + z3, FIX_0_541196100); /* c6 */
886 tmp0 = z1 + MULTIPLY(z2, FIX_0_765366865); /* c2-c6 */
887 tmp2 = z1 - MULTIPLY(z3, FIX_1_847759065); /* c2+c6 */
888
889 /* Final output stage */
890
891 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
892 CONST_BITS+PASS1_BITS+3)
893 & RANGE_MASK];
894 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
895 CONST_BITS+PASS1_BITS+3)
896 & RANGE_MASK];
897 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp2,
898 CONST_BITS+PASS1_BITS+3)
899 & RANGE_MASK];
900 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp2,
901 CONST_BITS+PASS1_BITS+3)
902 & RANGE_MASK];
903
904 wsptr += 4; /* advance pointer to next row */
905 }
906 }
907
908
909 /*
910 * Perform dequantization and inverse DCT on one block of coefficients,
911 * producing a reduced-size 3x3 output block.
912 *
913 * Optimized algorithm with 2 multiplications in the 1-D kernel.
914 * cK represents sqrt(2) * cos(K*pi/6).
915 */
916
917 GLOBAL(void)
918 jpeg_idct_3x3 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
919 JCOEFPTR coef_block,
920 JSAMPARRAY output_buf, JDIMENSION output_col)
921 {
922 INT32 tmp0, tmp2, tmp10, tmp12;
923 JCOEFPTR inptr;
924 ISLOW_MULT_TYPE * quantptr;
925 int * wsptr;
926 JSAMPROW outptr;
927 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
928 int ctr;
929 int workspace[3*3]; /* buffers data between passes */
930 SHIFT_TEMPS
931
932 /* Pass 1: process columns from input, store into work array. */
933
934 inptr = coef_block;
935 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
936 wsptr = workspace;
937 for (ctr = 0; ctr < 3; ctr++, inptr++, quantptr++, wsptr++) {
938 /* Even part */
939
940 tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
941 tmp0 <<= CONST_BITS;
942 /* Add fudge factor here for final descale. */
943 tmp0 += ONE << (CONST_BITS-PASS1_BITS-1);
944 tmp2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
945 tmp12 = MULTIPLY(tmp2, FIX(0.707106781)); /* c2 */
946 tmp10 = tmp0 + tmp12;
947 tmp2 = tmp0 - tmp12 - tmp12;
948
949 /* Odd part */
950
951 tmp12 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
952 tmp0 = MULTIPLY(tmp12, FIX(1.224744871)); /* c1 */
953
954 /* Final output stage */
955
956 wsptr[3*0] = (int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS-PASS1_BITS);
957 wsptr[3*2] = (int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS-PASS1_BITS);
958 wsptr[3*1] = (int) RIGHT_SHIFT(tmp2, CONST_BITS-PASS1_BITS);
959 }
960
961 /* Pass 2: process 3 rows from work array, store into output array. */
962
963 wsptr = workspace;
964 for (ctr = 0; ctr < 3; ctr++) {
965 outptr = output_buf[ctr] + output_col;
966
967 /* Even part */
968
969 /* Add fudge factor here for final descale. */
970 tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
971 tmp0 <<= CONST_BITS;
972 tmp2 = (INT32) wsptr[2];
973 tmp12 = MULTIPLY(tmp2, FIX(0.707106781)); /* c2 */
974 tmp10 = tmp0 + tmp12;
975 tmp2 = tmp0 - tmp12 - tmp12;
976
977 /* Odd part */
978
979 tmp12 = (INT32) wsptr[1];
980 tmp0 = MULTIPLY(tmp12, FIX(1.224744871)); /* c1 */
981
982 /* Final output stage */
983
984 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
985 CONST_BITS+PASS1_BITS+3)
986 & RANGE_MASK];
987 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
988 CONST_BITS+PASS1_BITS+3)
989 & RANGE_MASK];
990 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp2,
991 CONST_BITS+PASS1_BITS+3)
992 & RANGE_MASK];
993
994 wsptr += 3; /* advance pointer to next row */
995 }
996 }
997
998
999 /*
1000 * Perform dequantization and inverse DCT on one block of coefficients,
1001 * producing a reduced-size 2x2 output block.
1002 *
1003 * Multiplication-less algorithm.
1004 */
1005
1006 GLOBAL(void)
1007 jpeg_idct_2x2 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
1008 JCOEFPTR coef_block,
1009 JSAMPARRAY output_buf, JDIMENSION output_col)
1010 {
1011 INT32 tmp0, tmp1, tmp2, tmp3, tmp4, tmp5;
1012 ISLOW_MULT_TYPE * quantptr;
1013 JSAMPROW outptr;
1014 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
1015 SHIFT_TEMPS
1016
1017 /* Pass 1: process columns from input. */
1018
1019 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
1020
1021 /* Column 0 */
1022 tmp4 = DEQUANTIZE(coef_block[DCTSIZE*0], quantptr[DCTSIZE*0]);
1023 tmp5 = DEQUANTIZE(coef_block[DCTSIZE*1], quantptr[DCTSIZE*1]);
1024 /* Add fudge factor here for final descale. */
1025 tmp4 += ONE << 2;
1026
1027 tmp0 = tmp4 + tmp5;
1028 tmp2 = tmp4 - tmp5;
1029
1030 /* Column 1 */
1031 tmp4 = DEQUANTIZE(coef_block[DCTSIZE*0+1], quantptr[DCTSIZE*0+1]);
1032 tmp5 = DEQUANTIZE(coef_block[DCTSIZE*1+1], quantptr[DCTSIZE*1+1]);
1033
1034 tmp1 = tmp4 + tmp5;
1035 tmp3 = tmp4 - tmp5;
1036
1037 /* Pass 2: process 2 rows, store into output array. */
1038
1039 /* Row 0 */
1040 outptr = output_buf[0] + output_col;
1041
1042 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp0 + tmp1, 3) & RANGE_MASK];
1043 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp0 - tmp1, 3) & RANGE_MASK];
1044
1045 /* Row 1 */
1046 outptr = output_buf[1] + output_col;
1047
1048 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp2 + tmp3, 3) & RANGE_MASK];
1049 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp2 - tmp3, 3) & RANGE_MASK];
1050 }
1051
1052
1053 /*
1054 * Perform dequantization and inverse DCT on one block of coefficients,
1055 * producing a reduced-size 1x1 output block.
1056 *
1057 * We hardly need an inverse DCT routine for this: just take the
1058 * average pixel value, which is one-eighth of the DC coefficient.
1059 */
1060
1061 GLOBAL(void)
1062 jpeg_idct_1x1 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
1063 JCOEFPTR coef_block,
1064 JSAMPARRAY output_buf, JDIMENSION output_col)
1065 {
1066 int dcval;
1067 ISLOW_MULT_TYPE * quantptr;
1068 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
1069 SHIFT_TEMPS
1070
1071 /* 1x1 is trivial: just take the DC coefficient divided by 8. */
1072 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
1073 dcval = DEQUANTIZE(coef_block[0], quantptr[0]);
1074 dcval = (int) DESCALE((INT32) dcval, 3);
1075
1076 output_buf[0][output_col] = range_limit[dcval & RANGE_MASK];
1077 }
1078
1079
1080 /*
1081 * Perform dequantization and inverse DCT on one block of coefficients,
1082 * producing a 9x9 output block.
1083 *
1084 * Optimized algorithm with 10 multiplications in the 1-D kernel.
1085 * cK represents sqrt(2) * cos(K*pi/18).
1086 */
1087
1088 GLOBAL(void)
1089 jpeg_idct_9x9 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
1090 JCOEFPTR coef_block,
1091 JSAMPARRAY output_buf, JDIMENSION output_col)
1092 {
1093 INT32 tmp0, tmp1, tmp2, tmp3, tmp10, tmp11, tmp12, tmp13, tmp14;
1094 INT32 z1, z2, z3, z4;
1095 JCOEFPTR inptr;
1096 ISLOW_MULT_TYPE * quantptr;
1097 int * wsptr;
1098 JSAMPROW outptr;
1099 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
1100 int ctr;
1101 int workspace[8*9]; /* buffers data between passes */
1102 SHIFT_TEMPS
1103
1104 /* Pass 1: process columns from input, store into work array. */
1105
1106 inptr = coef_block;
1107 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
1108 wsptr = workspace;
1109 for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
1110 /* Even part */
1111
1112 tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
1113 tmp0 <<= CONST_BITS;
1114 /* Add fudge factor here for final descale. */
1115 tmp0 += ONE << (CONST_BITS-PASS1_BITS-1);
1116
1117 z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
1118 z2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
1119 z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
1120
1121 tmp3 = MULTIPLY(z3, FIX(0.707106781)); /* c6 */
1122 tmp1 = tmp0 + tmp3;
1123 tmp2 = tmp0 - tmp3 - tmp3;
1124
1125 tmp0 = MULTIPLY(z1 - z2, FIX(0.707106781)); /* c6 */
1126 tmp11 = tmp2 + tmp0;
1127 tmp14 = tmp2 - tmp0 - tmp0;
1128
1129 tmp0 = MULTIPLY(z1 + z2, FIX(1.328926049)); /* c2 */
1130 tmp2 = MULTIPLY(z1, FIX(1.083350441)); /* c4 */
1131 tmp3 = MULTIPLY(z2, FIX(0.245575608)); /* c8 */
1132
1133 tmp10 = tmp1 + tmp0 - tmp3;
1134 tmp12 = tmp1 - tmp0 + tmp2;
1135 tmp13 = tmp1 - tmp2 + tmp3;
1136
1137 /* Odd part */
1138
1139 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
1140 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
1141 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
1142 z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
1143
1144 z2 = MULTIPLY(z2, - FIX(1.224744871)); /* -c3 */
1145
1146 tmp2 = MULTIPLY(z1 + z3, FIX(0.909038955)); /* c5 */
1147 tmp3 = MULTIPLY(z1 + z4, FIX(0.483689525)); /* c7 */
1148 tmp0 = tmp2 + tmp3 - z2;
1149 tmp1 = MULTIPLY(z3 - z4, FIX(1.392728481)); /* c1 */
1150 tmp2 += z2 - tmp1;
1151 tmp3 += z2 + tmp1;
1152 tmp1 = MULTIPLY(z1 - z3 - z4, FIX(1.224744871)); /* c3 */
1153
1154 /* Final output stage */
1155
1156 wsptr[8*0] = (int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS-PASS1_BITS);
1157 wsptr[8*8] = (int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS-PASS1_BITS);
1158 wsptr[8*1] = (int) RIGHT_SHIFT(tmp11 + tmp1, CONST_BITS-PASS1_BITS);
1159 wsptr[8*7] = (int) RIGHT_SHIFT(tmp11 - tmp1, CONST_BITS-PASS1_BITS);
1160 wsptr[8*2] = (int) RIGHT_SHIFT(tmp12 + tmp2, CONST_BITS-PASS1_BITS);
1161 wsptr[8*6] = (int) RIGHT_SHIFT(tmp12 - tmp2, CONST_BITS-PASS1_BITS);
1162 wsptr[8*3] = (int) RIGHT_SHIFT(tmp13 + tmp3, CONST_BITS-PASS1_BITS);
1163 wsptr[8*5] = (int) RIGHT_SHIFT(tmp13 - tmp3, CONST_BITS-PASS1_BITS);
1164 wsptr[8*4] = (int) RIGHT_SHIFT(tmp14, CONST_BITS-PASS1_BITS);
1165 }
1166
1167 /* Pass 2: process 9 rows from work array, store into output array. */
1168
1169 wsptr = workspace;
1170 for (ctr = 0; ctr < 9; ctr++) {
1171 outptr = output_buf[ctr] + output_col;
1172
1173 /* Even part */
1174
1175 /* Add fudge factor here for final descale. */
1176 tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
1177 tmp0 <<= CONST_BITS;
1178
1179 z1 = (INT32) wsptr[2];
1180 z2 = (INT32) wsptr[4];
1181 z3 = (INT32) wsptr[6];
1182
1183 tmp3 = MULTIPLY(z3, FIX(0.707106781)); /* c6 */
1184 tmp1 = tmp0 + tmp3;
1185 tmp2 = tmp0 - tmp3 - tmp3;
1186
1187 tmp0 = MULTIPLY(z1 - z2, FIX(0.707106781)); /* c6 */
1188 tmp11 = tmp2 + tmp0;
1189 tmp14 = tmp2 - tmp0 - tmp0;
1190
1191 tmp0 = MULTIPLY(z1 + z2, FIX(1.328926049)); /* c2 */
1192 tmp2 = MULTIPLY(z1, FIX(1.083350441)); /* c4 */
1193 tmp3 = MULTIPLY(z2, FIX(0.245575608)); /* c8 */
1194
1195 tmp10 = tmp1 + tmp0 - tmp3;
1196 tmp12 = tmp1 - tmp0 + tmp2;
1197 tmp13 = tmp1 - tmp2 + tmp3;
1198
1199 /* Odd part */
1200
1201 z1 = (INT32) wsptr[1];
1202 z2 = (INT32) wsptr[3];
1203 z3 = (INT32) wsptr[5];
1204 z4 = (INT32) wsptr[7];
1205
1206 z2 = MULTIPLY(z2, - FIX(1.224744871)); /* -c3 */
1207
1208 tmp2 = MULTIPLY(z1 + z3, FIX(0.909038955)); /* c5 */
1209 tmp3 = MULTIPLY(z1 + z4, FIX(0.483689525)); /* c7 */
1210 tmp0 = tmp2 + tmp3 - z2;
1211 tmp1 = MULTIPLY(z3 - z4, FIX(1.392728481)); /* c1 */
1212 tmp2 += z2 - tmp1;
1213 tmp3 += z2 + tmp1;
1214 tmp1 = MULTIPLY(z1 - z3 - z4, FIX(1.224744871)); /* c3 */
1215
1216 /* Final output stage */
1217
1218 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
1219 CONST_BITS+PASS1_BITS+3)
1220 & RANGE_MASK];
1221 outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
1222 CONST_BITS+PASS1_BITS+3)
1223 & RANGE_MASK];
1224 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp1,
1225 CONST_BITS+PASS1_BITS+3)
1226 & RANGE_MASK];
1227 outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp1,
1228 CONST_BITS+PASS1_BITS+3)
1229 & RANGE_MASK];
1230 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp2,
1231 CONST_BITS+PASS1_BITS+3)
1232 & RANGE_MASK];
1233 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp2,
1234 CONST_BITS+PASS1_BITS+3)
1235 & RANGE_MASK];
1236 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp13 + tmp3,
1237 CONST_BITS+PASS1_BITS+3)
1238 & RANGE_MASK];
1239 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp13 - tmp3,
1240 CONST_BITS+PASS1_BITS+3)
1241 & RANGE_MASK];
1242 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp14,
1243 CONST_BITS+PASS1_BITS+3)
1244 & RANGE_MASK];
1245
1246 wsptr += 8; /* advance pointer to next row */
1247 }
1248 }
1249
1250
1251 /*
1252 * Perform dequantization and inverse DCT on one block of coefficients,
1253 * producing a 10x10 output block.
1254 *
1255 * Optimized algorithm with 12 multiplications in the 1-D kernel.
1256 * cK represents sqrt(2) * cos(K*pi/20).
1257 */
1258
1259 GLOBAL(void)
1260 jpeg_idct_10x10 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
1261 JCOEFPTR coef_block,
1262 JSAMPARRAY output_buf, JDIMENSION output_col)
1263 {
1264 INT32 tmp10, tmp11, tmp12, tmp13, tmp14;
1265 INT32 tmp20, tmp21, tmp22, tmp23, tmp24;
1266 INT32 z1, z2, z3, z4, z5;
1267 JCOEFPTR inptr;
1268 ISLOW_MULT_TYPE * quantptr;
1269 int * wsptr;
1270 JSAMPROW outptr;
1271 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
1272 int ctr;
1273 int workspace[8*10]; /* buffers data between passes */
1274 SHIFT_TEMPS
1275
1276 /* Pass 1: process columns from input, store into work array. */
1277
1278 inptr = coef_block;
1279 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
1280 wsptr = workspace;
1281 for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
1282 /* Even part */
1283
1284 z3 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
1285 z3 <<= CONST_BITS;
1286 /* Add fudge factor here for final descale. */
1287 z3 += ONE << (CONST_BITS-PASS1_BITS-1);
1288 z4 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
1289 z1 = MULTIPLY(z4, FIX(1.144122806)); /* c4 */
1290 z2 = MULTIPLY(z4, FIX(0.437016024)); /* c8 */
1291 tmp10 = z3 + z1;
1292 tmp11 = z3 - z2;
1293
1294 tmp22 = RIGHT_SHIFT(z3 - ((z1 - z2) << 1), /* c0 = (c4-c8)*2 */
1295 CONST_BITS-PASS1_BITS);
1296
1297 z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
1298 z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
1299
1300 z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c6 */
1301 tmp12 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c2-c6 */
1302 tmp13 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c2+c6 */
1303
1304 tmp20 = tmp10 + tmp12;
1305 tmp24 = tmp10 - tmp12;
1306 tmp21 = tmp11 + tmp13;
1307 tmp23 = tmp11 - tmp13;
1308
1309 /* Odd part */
1310
1311 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
1312 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
1313 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
1314 z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
1315
1316 tmp11 = z2 + z4;
1317 tmp13 = z2 - z4;
1318
1319 tmp12 = MULTIPLY(tmp13, FIX(0.309016994)); /* (c3-c7)/2 */
1320 z5 = z3 << CONST_BITS;
1321
1322 z2 = MULTIPLY(tmp11, FIX(0.951056516)); /* (c3+c7)/2 */
1323 z4 = z5 + tmp12;
1324
1325 tmp10 = MULTIPLY(z1, FIX(1.396802247)) + z2 + z4; /* c1 */
1326 tmp14 = MULTIPLY(z1, FIX(0.221231742)) - z2 + z4; /* c9 */
1327
1328 z2 = MULTIPLY(tmp11, FIX(0.587785252)); /* (c1-c9)/2 */
1329 z4 = z5 - tmp12 - (tmp13 << (CONST_BITS - 1));
1330
1331 tmp12 = (z1 - tmp13 - z3) << PASS1_BITS;
1332
1333 tmp11 = MULTIPLY(z1, FIX(1.260073511)) - z2 - z4; /* c3 */
1334 tmp13 = MULTIPLY(z1, FIX(0.642039522)) - z2 + z4; /* c7 */
1335
1336 /* Final output stage */
1337
1338 wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
1339 wsptr[8*9] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
1340 wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
1341 wsptr[8*8] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
1342 wsptr[8*2] = (int) (tmp22 + tmp12);
1343 wsptr[8*7] = (int) (tmp22 - tmp12);
1344 wsptr[8*3] = (int) RIGHT_SHIFT(tmp23 + tmp13, CONST_BITS-PASS1_BITS);
1345 wsptr[8*6] = (int) RIGHT_SHIFT(tmp23 - tmp13, CONST_BITS-PASS1_BITS);
1346 wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
1347 wsptr[8*5] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
1348 }
1349
1350 /* Pass 2: process 10 rows from work array, store into output array. */
1351
1352 wsptr = workspace;
1353 for (ctr = 0; ctr < 10; ctr++) {
1354 outptr = output_buf[ctr] + output_col;
1355
1356 /* Even part */
1357
1358 /* Add fudge factor here for final descale. */
1359 z3 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
1360 z3 <<= CONST_BITS;
1361 z4 = (INT32) wsptr[4];
1362 z1 = MULTIPLY(z4, FIX(1.144122806)); /* c4 */
1363 z2 = MULTIPLY(z4, FIX(0.437016024)); /* c8 */
1364 tmp10 = z3 + z1;
1365 tmp11 = z3 - z2;
1366
1367 tmp22 = z3 - ((z1 - z2) << 1); /* c0 = (c4-c8)*2 */
1368
1369 z2 = (INT32) wsptr[2];
1370 z3 = (INT32) wsptr[6];
1371
1372 z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c6 */
1373 tmp12 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c2-c6 */
1374 tmp13 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c2+c6 */
1375
1376 tmp20 = tmp10 + tmp12;
1377 tmp24 = tmp10 - tmp12;
1378 tmp21 = tmp11 + tmp13;
1379 tmp23 = tmp11 - tmp13;
1380
1381 /* Odd part */
1382
1383 z1 = (INT32) wsptr[1];
1384 z2 = (INT32) wsptr[3];
1385 z3 = (INT32) wsptr[5];
1386 z3 <<= CONST_BITS;
1387 z4 = (INT32) wsptr[7];
1388
1389 tmp11 = z2 + z4;
1390 tmp13 = z2 - z4;
1391
1392 tmp12 = MULTIPLY(tmp13, FIX(0.309016994)); /* (c3-c7)/2 */
1393
1394 z2 = MULTIPLY(tmp11, FIX(0.951056516)); /* (c3+c7)/2 */
1395 z4 = z3 + tmp12;
1396
1397 tmp10 = MULTIPLY(z1, FIX(1.396802247)) + z2 + z4; /* c1 */
1398 tmp14 = MULTIPLY(z1, FIX(0.221231742)) - z2 + z4; /* c9 */
1399
1400 z2 = MULTIPLY(tmp11, FIX(0.587785252)); /* (c1-c9)/2 */
1401 z4 = z3 - tmp12 - (tmp13 << (CONST_BITS - 1));
1402
1403 tmp12 = ((z1 - tmp13) << CONST_BITS) - z3;
1404
1405 tmp11 = MULTIPLY(z1, FIX(1.260073511)) - z2 - z4; /* c3 */
1406 tmp13 = MULTIPLY(z1, FIX(0.642039522)) - z2 + z4; /* c7 */
1407
1408 /* Final output stage */
1409
1410 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
1411 CONST_BITS+PASS1_BITS+3)
1412 & RANGE_MASK];
1413 outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
1414 CONST_BITS+PASS1_BITS+3)
1415 & RANGE_MASK];
1416 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
1417 CONST_BITS+PASS1_BITS+3)
1418 & RANGE_MASK];
1419 outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
1420 CONST_BITS+PASS1_BITS+3)
1421 & RANGE_MASK];
1422 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
1423 CONST_BITS+PASS1_BITS+3)
1424 & RANGE_MASK];
1425 outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
1426 CONST_BITS+PASS1_BITS+3)
1427 & RANGE_MASK];
1428 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
1429 CONST_BITS+PASS1_BITS+3)
1430 & RANGE_MASK];
1431 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
1432 CONST_BITS+PASS1_BITS+3)
1433 & RANGE_MASK];
1434 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
1435 CONST_BITS+PASS1_BITS+3)
1436 & RANGE_MASK];
1437 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
1438 CONST_BITS+PASS1_BITS+3)
1439 & RANGE_MASK];
1440
1441 wsptr += 8; /* advance pointer to next row */
1442 }
1443 }
1444
1445
1446 /*
1447 * Perform dequantization and inverse DCT on one block of coefficients,
1448 * producing a 11x11 output block.
1449 *
1450 * Optimized algorithm with 24 multiplications in the 1-D kernel.
1451 * cK represents sqrt(2) * cos(K*pi/22).
1452 */
1453
1454 GLOBAL(void)
1455 jpeg_idct_11x11 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
1456 JCOEFPTR coef_block,
1457 JSAMPARRAY output_buf, JDIMENSION output_col)
1458 {
1459 INT32 tmp10, tmp11, tmp12, tmp13, tmp14;
1460 INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25;
1461 INT32 z1, z2, z3, z4;
1462 JCOEFPTR inptr;
1463 ISLOW_MULT_TYPE * quantptr;
1464 int * wsptr;
1465 JSAMPROW outptr;
1466 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
1467 int ctr;
1468 int workspace[8*11]; /* buffers data between passes */
1469 SHIFT_TEMPS
1470
1471 /* Pass 1: process columns from input, store into work array. */
1472
1473 inptr = coef_block;
1474 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
1475 wsptr = workspace;
1476 for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
1477 /* Even part */
1478
1479 tmp10 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
1480 tmp10 <<= CONST_BITS;
1481 /* Add fudge factor here for final descale. */
1482 tmp10 += ONE << (CONST_BITS-PASS1_BITS-1);
1483
1484 z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
1485 z2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
1486 z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
1487
1488 tmp20 = MULTIPLY(z2 - z3, FIX(2.546640132)); /* c2+c4 */
1489 tmp23 = MULTIPLY(z2 - z1, FIX(0.430815045)); /* c2-c6 */
1490 z4 = z1 + z3;
1491 tmp24 = MULTIPLY(z4, - FIX(1.155664402)); /* -(c2-c10) */
1492 z4 -= z2;
1493 tmp25 = tmp10 + MULTIPLY(z4, FIX(1.356927976)); /* c2 */
1494 tmp21 = tmp20 + tmp23 + tmp25 -
1495 MULTIPLY(z2, FIX(1.821790775)); /* c2+c4+c10-c6 */
1496 tmp20 += tmp25 + MULTIPLY(z3, FIX(2.115825087)); /* c4+c6 */
1497 tmp23 += tmp25 - MULTIPLY(z1, FIX(1.513598477)); /* c6+c8 */
1498 tmp24 += tmp25;
1499 tmp22 = tmp24 - MULTIPLY(z3, FIX(0.788749120)); /* c8+c10 */
1500 tmp24 += MULTIPLY(z2, FIX(1.944413522)) - /* c2+c8 */
1501 MULTIPLY(z1, FIX(1.390975730)); /* c4+c10 */
1502 tmp25 = tmp10 - MULTIPLY(z4, FIX(1.414213562)); /* c0 */
1503
1504 /* Odd part */
1505
1506 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
1507 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
1508 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
1509 z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
1510
1511 tmp11 = z1 + z2;
1512 tmp14 = MULTIPLY(tmp11 + z3 + z4, FIX(0.398430003)); /* c9 */
1513 tmp11 = MULTIPLY(tmp11, FIX(0.887983902)); /* c3-c9 */
1514 tmp12 = MULTIPLY(z1 + z3, FIX(0.670361295)); /* c5-c9 */
1515 tmp13 = tmp14 + MULTIPLY(z1 + z4, FIX(0.366151574)); /* c7-c9 */
1516 tmp10 = tmp11 + tmp12 + tmp13 -
1517 MULTIPLY(z1, FIX(0.923107866)); /* c7+c5+c3-c1-2*c9 */
1518 z1 = tmp14 - MULTIPLY(z2 + z3, FIX(1.163011579)); /* c7+c9 */
1519 tmp11 += z1 + MULTIPLY(z2, FIX(2.073276588)); /* c1+c7+3*c9-c3 */
1520 tmp12 += z1 - MULTIPLY(z3, FIX(1.192193623)); /* c3+c5-c7-c9 */
1521 z1 = MULTIPLY(z2 + z4, - FIX(1.798248910)); /* -(c1+c9) */
1522 tmp11 += z1;
1523 tmp13 += z1 + MULTIPLY(z4, FIX(2.102458632)); /* c1+c5+c9-c7 */
1524 tmp14 += MULTIPLY(z2, - FIX(1.467221301)) + /* -(c5+c9) */
1525 MULTIPLY(z3, FIX(1.001388905)) - /* c1-c9 */
1526 MULTIPLY(z4, FIX(1.684843907)); /* c3+c9 */
1527
1528 /* Final output stage */
1529
1530 wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
1531 wsptr[8*10] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
1532 wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
1533 wsptr[8*9] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
1534 wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
1535 wsptr[8*8] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
1536 wsptr[8*3] = (int) RIGHT_SHIFT(tmp23 + tmp13, CONST_BITS-PASS1_BITS);
1537 wsptr[8*7] = (int) RIGHT_SHIFT(tmp23 - tmp13, CONST_BITS-PASS1_BITS);
1538 wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
1539 wsptr[8*6] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
1540 wsptr[8*5] = (int) RIGHT_SHIFT(tmp25, CONST_BITS-PASS1_BITS);
1541 }
1542
1543 /* Pass 2: process 11 rows from work array, store into output array. */
1544
1545 wsptr = workspace;
1546 for (ctr = 0; ctr < 11; ctr++) {
1547 outptr = output_buf[ctr] + output_col;
1548
1549 /* Even part */
1550
1551 /* Add fudge factor here for final descale. */
1552 tmp10 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
1553 tmp10 <<= CONST_BITS;
1554
1555 z1 = (INT32) wsptr[2];
1556 z2 = (INT32) wsptr[4];
1557 z3 = (INT32) wsptr[6];
1558
1559 tmp20 = MULTIPLY(z2 - z3, FIX(2.546640132)); /* c2+c4 */
1560 tmp23 = MULTIPLY(z2 - z1, FIX(0.430815045)); /* c2-c6 */
1561 z4 = z1 + z3;
1562 tmp24 = MULTIPLY(z4, - FIX(1.155664402)); /* -(c2-c10) */
1563 z4 -= z2;
1564 tmp25 = tmp10 + MULTIPLY(z4, FIX(1.356927976)); /* c2 */
1565 tmp21 = tmp20 + tmp23 + tmp25 -
1566 MULTIPLY(z2, FIX(1.821790775)); /* c2+c4+c10-c6 */
1567 tmp20 += tmp25 + MULTIPLY(z3, FIX(2.115825087)); /* c4+c6 */
1568 tmp23 += tmp25 - MULTIPLY(z1, FIX(1.513598477)); /* c6+c8 */
1569 tmp24 += tmp25;
1570 tmp22 = tmp24 - MULTIPLY(z3, FIX(0.788749120)); /* c8+c10 */
1571 tmp24 += MULTIPLY(z2, FIX(1.944413522)) - /* c2+c8 */
1572 MULTIPLY(z1, FIX(1.390975730)); /* c4+c10 */
1573 tmp25 = tmp10 - MULTIPLY(z4, FIX(1.414213562)); /* c0 */
1574
1575 /* Odd part */
1576
1577 z1 = (INT32) wsptr[1];
1578 z2 = (INT32) wsptr[3];
1579 z3 = (INT32) wsptr[5];
1580 z4 = (INT32) wsptr[7];
1581
1582 tmp11 = z1 + z2;
1583 tmp14 = MULTIPLY(tmp11 + z3 + z4, FIX(0.398430003)); /* c9 */
1584 tmp11 = MULTIPLY(tmp11, FIX(0.887983902)); /* c3-c9 */
1585 tmp12 = MULTIPLY(z1 + z3, FIX(0.670361295)); /* c5-c9 */
1586 tmp13 = tmp14 + MULTIPLY(z1 + z4, FIX(0.366151574)); /* c7-c9 */
1587 tmp10 = tmp11 + tmp12 + tmp13 -
1588 MULTIPLY(z1, FIX(0.923107866)); /* c7+c5+c3-c1-2*c9 */
1589 z1 = tmp14 - MULTIPLY(z2 + z3, FIX(1.163011579)); /* c7+c9 */
1590 tmp11 += z1 + MULTIPLY(z2, FIX(2.073276588)); /* c1+c7+3*c9-c3 */
1591 tmp12 += z1 - MULTIPLY(z3, FIX(1.192193623)); /* c3+c5-c7-c9 */
1592 z1 = MULTIPLY(z2 + z4, - FIX(1.798248910)); /* -(c1+c9) */
1593 tmp11 += z1;
1594 tmp13 += z1 + MULTIPLY(z4, FIX(2.102458632)); /* c1+c5+c9-c7 */
1595 tmp14 += MULTIPLY(z2, - FIX(1.467221301)) + /* -(c5+c9) */
1596 MULTIPLY(z3, FIX(1.001388905)) - /* c1-c9 */
1597 MULTIPLY(z4, FIX(1.684843907)); /* c3+c9 */
1598
1599 /* Final output stage */
1600
1601 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
1602 CONST_BITS+PASS1_BITS+3)
1603 & RANGE_MASK];
1604 outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
1605 CONST_BITS+PASS1_BITS+3)
1606 & RANGE_MASK];
1607 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
1608 CONST_BITS+PASS1_BITS+3)
1609 & RANGE_MASK];
1610 outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
1611 CONST_BITS+PASS1_BITS+3)
1612 & RANGE_MASK];
1613 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
1614 CONST_BITS+PASS1_BITS+3)
1615 & RANGE_MASK];
1616 outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
1617 CONST_BITS+PASS1_BITS+3)
1618 & RANGE_MASK];
1619 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
1620 CONST_BITS+PASS1_BITS+3)
1621 & RANGE_MASK];
1622 outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
1623 CONST_BITS+PASS1_BITS+3)
1624 & RANGE_MASK];
1625 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
1626 CONST_BITS+PASS1_BITS+3)
1627 & RANGE_MASK];
1628 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
1629 CONST_BITS+PASS1_BITS+3)
1630 & RANGE_MASK];
1631 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25,
1632 CONST_BITS+PASS1_BITS+3)
1633 & RANGE_MASK];
1634
1635 wsptr += 8; /* advance pointer to next row */
1636 }
1637 }
1638
1639
1640 /*
1641 * Perform dequantization and inverse DCT on one block of coefficients,
1642 * producing a 12x12 output block.
1643 *
1644 * Optimized algorithm with 15 multiplications in the 1-D kernel.
1645 * cK represents sqrt(2) * cos(K*pi/24).
1646 */
1647
1648 GLOBAL(void)
1649 jpeg_idct_12x12 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
1650 JCOEFPTR coef_block,
1651 JSAMPARRAY output_buf, JDIMENSION output_col)
1652 {
1653 INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15;
1654 INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25;
1655 INT32 z1, z2, z3, z4;
1656 JCOEFPTR inptr;
1657 ISLOW_MULT_TYPE * quantptr;
1658 int * wsptr;
1659 JSAMPROW outptr;
1660 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
1661 int ctr;
1662 int workspace[8*12]; /* buffers data between passes */
1663 SHIFT_TEMPS
1664
1665 /* Pass 1: process columns from input, store into work array. */
1666
1667 inptr = coef_block;
1668 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
1669 wsptr = workspace;
1670 for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
1671 /* Even part */
1672
1673 z3 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
1674 z3 <<= CONST_BITS;
1675 /* Add fudge factor here for final descale. */
1676 z3 += ONE << (CONST_BITS-PASS1_BITS-1);
1677
1678 z4 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
1679 z4 = MULTIPLY(z4, FIX(1.224744871)); /* c4 */
1680
1681 tmp10 = z3 + z4;
1682 tmp11 = z3 - z4;
1683
1684 z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
1685 z4 = MULTIPLY(z1, FIX(1.366025404)); /* c2 */
1686 z1 <<= CONST_BITS;
1687 z2 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
1688 z2 <<= CONST_BITS;
1689
1690 tmp12 = z1 - z2;
1691
1692 tmp21 = z3 + tmp12;
1693 tmp24 = z3 - tmp12;
1694
1695 tmp12 = z4 + z2;
1696
1697 tmp20 = tmp10 + tmp12;
1698 tmp25 = tmp10 - tmp12;
1699
1700 tmp12 = z4 - z1 - z2;
1701
1702 tmp22 = tmp11 + tmp12;
1703 tmp23 = tmp11 - tmp12;
1704
1705 /* Odd part */
1706
1707 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
1708 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
1709 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
1710 z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
1711
1712 tmp11 = MULTIPLY(z2, FIX(1.306562965)); /* c3 */
1713 tmp14 = MULTIPLY(z2, - FIX_0_541196100); /* -c9 */
1714
1715 tmp10 = z1 + z3;
1716 tmp15 = MULTIPLY(tmp10 + z4, FIX(0.860918669)); /* c7 */
1717 tmp12 = tmp15 + MULTIPLY(tmp10, FIX(0.261052384)); /* c5-c7 */
1718 tmp10 = tmp12 + tmp11 + MULTIPLY(z1, FIX(0.280143716)); /* c1-c5 */
1719 tmp13 = MULTIPLY(z3 + z4, - FIX(1.045510580)); /* -(c7+c11) */
1720 tmp12 += tmp13 + tmp14 - MULTIPLY(z3, FIX(1.478575242)); /* c1+c5-c7-c11 */
1721 tmp13 += tmp15 - tmp11 + MULTIPLY(z4, FIX(1.586706681)); /* c1+c11 */
1722 tmp15 += tmp14 - MULTIPLY(z1, FIX(0.676326758)) - /* c7-c11 */
1723 MULTIPLY(z4, FIX(1.982889723)); /* c5+c7 */
1724
1725 z1 -= z4;
1726 z2 -= z3;
1727 z3 = MULTIPLY(z1 + z2, FIX_0_541196100); /* c9 */
1728 tmp11 = z3 + MULTIPLY(z1, FIX_0_765366865); /* c3-c9 */
1729 tmp14 = z3 - MULTIPLY(z2, FIX_1_847759065); /* c3+c9 */
1730
1731 /* Final output stage */
1732
1733 wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
1734 wsptr[8*11] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
1735 wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
1736 wsptr[8*10] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
1737 wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
1738 wsptr[8*9] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
1739 wsptr[8*3] = (int) RIGHT_SHIFT(tmp23 + tmp13, CONST_BITS-PASS1_BITS);
1740 wsptr[8*8] = (int) RIGHT_SHIFT(tmp23 - tmp13, CONST_BITS-PASS1_BITS);
1741 wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
1742 wsptr[8*7] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
1743 wsptr[8*5] = (int) RIGHT_SHIFT(tmp25 + tmp15, CONST_BITS-PASS1_BITS);
1744 wsptr[8*6] = (int) RIGHT_SHIFT(tmp25 - tmp15, CONST_BITS-PASS1_BITS);
1745 }
1746
1747 /* Pass 2: process 12 rows from work array, store into output array. */
1748
1749 wsptr = workspace;
1750 for (ctr = 0; ctr < 12; ctr++) {
1751 outptr = output_buf[ctr] + output_col;
1752
1753 /* Even part */
1754
1755 /* Add fudge factor here for final descale. */
1756 z3 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
1757 z3 <<= CONST_BITS;
1758
1759 z4 = (INT32) wsptr[4];
1760 z4 = MULTIPLY(z4, FIX(1.224744871)); /* c4 */
1761
1762 tmp10 = z3 + z4;
1763 tmp11 = z3 - z4;
1764
1765 z1 = (INT32) wsptr[2];
1766 z4 = MULTIPLY(z1, FIX(1.366025404)); /* c2 */
1767 z1 <<= CONST_BITS;
1768 z2 = (INT32) wsptr[6];
1769 z2 <<= CONST_BITS;
1770
1771 tmp12 = z1 - z2;
1772
1773 tmp21 = z3 + tmp12;
1774 tmp24 = z3 - tmp12;
1775
1776 tmp12 = z4 + z2;
1777
1778 tmp20 = tmp10 + tmp12;
1779 tmp25 = tmp10 - tmp12;
1780
1781 tmp12 = z4 - z1 - z2;
1782
1783 tmp22 = tmp11 + tmp12;
1784 tmp23 = tmp11 - tmp12;
1785
1786 /* Odd part */
1787
1788 z1 = (INT32) wsptr[1];
1789 z2 = (INT32) wsptr[3];
1790 z3 = (INT32) wsptr[5];
1791 z4 = (INT32) wsptr[7];
1792
1793 tmp11 = MULTIPLY(z2, FIX(1.306562965)); /* c3 */
1794 tmp14 = MULTIPLY(z2, - FIX_0_541196100); /* -c9 */
1795
1796 tmp10 = z1 + z3;
1797 tmp15 = MULTIPLY(tmp10 + z4, FIX(0.860918669)); /* c7 */
1798 tmp12 = tmp15 + MULTIPLY(tmp10, FIX(0.261052384)); /* c5-c7 */
1799 tmp10 = tmp12 + tmp11 + MULTIPLY(z1, FIX(0.280143716)); /* c1-c5 */
1800 tmp13 = MULTIPLY(z3 + z4, - FIX(1.045510580)); /* -(c7+c11) */
1801 tmp12 += tmp13 + tmp14 - MULTIPLY(z3, FIX(1.478575242)); /* c1+c5-c7-c11 */
1802 tmp13 += tmp15 - tmp11 + MULTIPLY(z4, FIX(1.586706681)); /* c1+c11 */
1803 tmp15 += tmp14 - MULTIPLY(z1, FIX(0.676326758)) - /* c7-c11 */
1804 MULTIPLY(z4, FIX(1.982889723)); /* c5+c7 */
1805
1806 z1 -= z4;
1807 z2 -= z3;
1808 z3 = MULTIPLY(z1 + z2, FIX_0_541196100); /* c9 */
1809 tmp11 = z3 + MULTIPLY(z1, FIX_0_765366865); /* c3-c9 */
1810 tmp14 = z3 - MULTIPLY(z2, FIX_1_847759065); /* c3+c9 */
1811
1812 /* Final output stage */
1813
1814 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
1815 CONST_BITS+PASS1_BITS+3)
1816 & RANGE_MASK];
1817 outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
1818 CONST_BITS+PASS1_BITS+3)
1819 & RANGE_MASK];
1820 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
1821 CONST_BITS+PASS1_BITS+3)
1822 & RANGE_MASK];
1823 outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
1824 CONST_BITS+PASS1_BITS+3)
1825 & RANGE_MASK];
1826 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
1827 CONST_BITS+PASS1_BITS+3)
1828 & RANGE_MASK];
1829 outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
1830 CONST_BITS+PASS1_BITS+3)
1831 & RANGE_MASK];
1832 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
1833 CONST_BITS+PASS1_BITS+3)
1834 & RANGE_MASK];
1835 outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
1836 CONST_BITS+PASS1_BITS+3)
1837 & RANGE_MASK];
1838 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
1839 CONST_BITS+PASS1_BITS+3)
1840 & RANGE_MASK];
1841 outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
1842 CONST_BITS+PASS1_BITS+3)
1843 & RANGE_MASK];
1844 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp15,
1845 CONST_BITS+PASS1_BITS+3)
1846 & RANGE_MASK];
1847 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp15,
1848 CONST_BITS+PASS1_BITS+3)
1849 & RANGE_MASK];
1850
1851 wsptr += 8; /* advance pointer to next row */
1852 }
1853 }
1854
1855
1856 /*
1857 * Perform dequantization and inverse DCT on one block of coefficients,
1858 * producing a 13x13 output block.
1859 *
1860 * Optimized algorithm with 29 multiplications in the 1-D kernel.
1861 * cK represents sqrt(2) * cos(K*pi/26).
1862 */
1863
1864 GLOBAL(void)
1865 jpeg_idct_13x13 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
1866 JCOEFPTR coef_block,
1867 JSAMPARRAY output_buf, JDIMENSION output_col)
1868 {
1869 INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15;
1870 INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26;
1871 INT32 z1, z2, z3, z4;
1872 JCOEFPTR inptr;
1873 ISLOW_MULT_TYPE * quantptr;
1874 int * wsptr;
1875 JSAMPROW outptr;
1876 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
1877 int ctr;
1878 int workspace[8*13]; /* buffers data between passes */
1879 SHIFT_TEMPS
1880
1881 /* Pass 1: process columns from input, store into work array. */
1882
1883 inptr = coef_block;
1884 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
1885 wsptr = workspace;
1886 for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
1887 /* Even part */
1888
1889 z1 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
1890 z1 <<= CONST_BITS;
1891 /* Add fudge factor here for final descale. */
1892 z1 += ONE << (CONST_BITS-PASS1_BITS-1);
1893
1894 z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
1895 z3 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
1896 z4 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
1897
1898 tmp10 = z3 + z4;
1899 tmp11 = z3 - z4;
1900
1901 tmp12 = MULTIPLY(tmp10, FIX(1.155388986)); /* (c4+c6)/2 */
1902 tmp13 = MULTIPLY(tmp11, FIX(0.096834934)) + z1; /* (c4-c6)/2 */
1903
1904 tmp20 = MULTIPLY(z2, FIX(1.373119086)) + tmp12 + tmp13; /* c2 */
1905 tmp22 = MULTIPLY(z2, FIX(0.501487041)) - tmp12 + tmp13; /* c10 */
1906
1907 tmp12 = MULTIPLY(tmp10, FIX(0.316450131)); /* (c8-c12)/2 */
1908 tmp13 = MULTIPLY(tmp11, FIX(0.486914739)) + z1; /* (c8+c12)/2 */
1909
1910 tmp21 = MULTIPLY(z2, FIX(1.058554052)) - tmp12 + tmp13; /* c6 */
1911 tmp25 = MULTIPLY(z2, - FIX(1.252223920)) + tmp12 + tmp13; /* c4 */
1912
1913 tmp12 = MULTIPLY(tmp10, FIX(0.435816023)); /* (c2-c10)/2 */
1914 tmp13 = MULTIPLY(tmp11, FIX(0.937303064)) - z1; /* (c2+c10)/2 */
1915
1916 tmp23 = MULTIPLY(z2, - FIX(0.170464608)) - tmp12 - tmp13; /* c12 */
1917 tmp24 = MULTIPLY(z2, - FIX(0.803364869)) + tmp12 - tmp13; /* c8 */
1918
1919 tmp26 = MULTIPLY(tmp11 - z2, FIX(1.414213562)) + z1; /* c0 */
1920
1921 /* Odd part */
1922
1923 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
1924 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
1925 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
1926 z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
1927
1928 tmp11 = MULTIPLY(z1 + z2, FIX(1.322312651)); /* c3 */
1929 tmp12 = MULTIPLY(z1 + z3, FIX(1.163874945)); /* c5 */
1930 tmp15 = z1 + z4;
1931 tmp13 = MULTIPLY(tmp15, FIX(0.937797057)); /* c7 */
1932 tmp10 = tmp11 + tmp12 + tmp13 -
1933 MULTIPLY(z1, FIX(2.020082300)); /* c7+c5+c3-c1 */
1934 tmp14 = MULTIPLY(z2 + z3, - FIX(0.338443458)); /* -c11 */
1935 tmp11 += tmp14 + MULTIPLY(z2, FIX(0.837223564)); /* c5+c9+c11-c3 */
1936 tmp12 += tmp14 - MULTIPLY(z3, FIX(1.572116027)); /* c1+c5-c9-c11 */
1937 tmp14 = MULTIPLY(z2 + z4, - FIX(1.163874945)); /* -c5 */
1938 tmp11 += tmp14;
1939 tmp13 += tmp14 + MULTIPLY(z4, FIX(2.205608352)); /* c3+c5+c9-c7 */
1940 tmp14 = MULTIPLY(z3 + z4, - FIX(0.657217813)); /* -c9 */
1941 tmp12 += tmp14;
1942 tmp13 += tmp14;
1943 tmp15 = MULTIPLY(tmp15, FIX(0.338443458)); /* c11 */
1944 tmp14 = tmp15 + MULTIPLY(z1, FIX(0.318774355)) - /* c9-c11 */
1945 MULTIPLY(z2, FIX(0.466105296)); /* c1-c7 */
1946 z1 = MULTIPLY(z3 - z2, FIX(0.937797057)); /* c7 */
1947 tmp14 += z1;
1948 tmp15 += z1 + MULTIPLY(z3, FIX(0.384515595)) - /* c3-c7 */
1949 MULTIPLY(z4, FIX(1.742345811)); /* c1+c11 */
1950
1951 /* Final output stage */
1952
1953 wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
1954 wsptr[8*12] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
1955 wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
1956 wsptr[8*11] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
1957 wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
1958 wsptr[8*10] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
1959 wsptr[8*3] = (int) RIGHT_SHIFT(tmp23 + tmp13, CONST_BITS-PASS1_BITS);
1960 wsptr[8*9] = (int) RIGHT_SHIFT(tmp23 - tmp13, CONST_BITS-PASS1_BITS);
1961 wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
1962 wsptr[8*8] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
1963 wsptr[8*5] = (int) RIGHT_SHIFT(tmp25 + tmp15, CONST_BITS-PASS1_BITS);
1964 wsptr[8*7] = (int) RIGHT_SHIFT(tmp25 - tmp15, CONST_BITS-PASS1_BITS);
1965 wsptr[8*6] = (int) RIGHT_SHIFT(tmp26, CONST_BITS-PASS1_BITS);
1966 }
1967
1968 /* Pass 2: process 13 rows from work array, store into output array. */
1969
1970 wsptr = workspace;
1971 for (ctr = 0; ctr < 13; ctr++) {
1972 outptr = output_buf[ctr] + output_col;
1973
1974 /* Even part */
1975
1976 /* Add fudge factor here for final descale. */
1977 z1 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
1978 z1 <<= CONST_BITS;
1979
1980 z2 = (INT32) wsptr[2];
1981 z3 = (INT32) wsptr[4];
1982 z4 = (INT32) wsptr[6];
1983
1984 tmp10 = z3 + z4;
1985 tmp11 = z3 - z4;
1986
1987 tmp12 = MULTIPLY(tmp10, FIX(1.155388986)); /* (c4+c6)/2 */
1988 tmp13 = MULTIPLY(tmp11, FIX(0.096834934)) + z1; /* (c4-c6)/2 */
1989
1990 tmp20 = MULTIPLY(z2, FIX(1.373119086)) + tmp12 + tmp13; /* c2 */
1991 tmp22 = MULTIPLY(z2, FIX(0.501487041)) - tmp12 + tmp13; /* c10 */
1992
1993 tmp12 = MULTIPLY(tmp10, FIX(0.316450131)); /* (c8-c12)/2 */
1994 tmp13 = MULTIPLY(tmp11, FIX(0.486914739)) + z1; /* (c8+c12)/2 */
1995
1996 tmp21 = MULTIPLY(z2, FIX(1.058554052)) - tmp12 + tmp13; /* c6 */
1997 tmp25 = MULTIPLY(z2, - FIX(1.252223920)) + tmp12 + tmp13; /* c4 */
1998
1999 tmp12 = MULTIPLY(tmp10, FIX(0.435816023)); /* (c2-c10)/2 */
2000 tmp13 = MULTIPLY(tmp11, FIX(0.937303064)) - z1; /* (c2+c10)/2 */
2001
2002 tmp23 = MULTIPLY(z2, - FIX(0.170464608)) - tmp12 - tmp13; /* c12 */
2003 tmp24 = MULTIPLY(z2, - FIX(0.803364869)) + tmp12 - tmp13; /* c8 */
2004
2005 tmp26 = MULTIPLY(tmp11 - z2, FIX(1.414213562)) + z1; /* c0 */
2006
2007 /* Odd part */
2008
2009 z1 = (INT32) wsptr[1];
2010 z2 = (INT32) wsptr[3];
2011 z3 = (INT32) wsptr[5];
2012 z4 = (INT32) wsptr[7];
2013
2014 tmp11 = MULTIPLY(z1 + z2, FIX(1.322312651)); /* c3 */
2015 tmp12 = MULTIPLY(z1 + z3, FIX(1.163874945)); /* c5 */
2016 tmp15 = z1 + z4;
2017 tmp13 = MULTIPLY(tmp15, FIX(0.937797057)); /* c7 */
2018 tmp10 = tmp11 + tmp12 + tmp13 -
2019 MULTIPLY(z1, FIX(2.020082300)); /* c7+c5+c3-c1 */
2020 tmp14 = MULTIPLY(z2 + z3, - FIX(0.338443458)); /* -c11 */
2021 tmp11 += tmp14 + MULTIPLY(z2, FIX(0.837223564)); /* c5+c9+c11-c3 */
2022 tmp12 += tmp14 - MULTIPLY(z3, FIX(1.572116027)); /* c1+c5-c9-c11 */
2023 tmp14 = MULTIPLY(z2 + z4, - FIX(1.163874945)); /* -c5 */
2024 tmp11 += tmp14;
2025 tmp13 += tmp14 + MULTIPLY(z4, FIX(2.205608352)); /* c3+c5+c9-c7 */
2026 tmp14 = MULTIPLY(z3 + z4, - FIX(0.657217813)); /* -c9 */
2027 tmp12 += tmp14;
2028 tmp13 += tmp14;
2029 tmp15 = MULTIPLY(tmp15, FIX(0.338443458)); /* c11 */
2030 tmp14 = tmp15 + MULTIPLY(z1, FIX(0.318774355)) - /* c9-c11 */
2031 MULTIPLY(z2, FIX(0.466105296)); /* c1-c7 */
2032 z1 = MULTIPLY(z3 - z2, FIX(0.937797057)); /* c7 */
2033 tmp14 += z1;
2034 tmp15 += z1 + MULTIPLY(z3, FIX(0.384515595)) - /* c3-c7 */
2035 MULTIPLY(z4, FIX(1.742345811)); /* c1+c11 */
2036
2037 /* Final output stage */
2038
2039 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
2040 CONST_BITS+PASS1_BITS+3)
2041 & RANGE_MASK];
2042 outptr[12] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
2043 CONST_BITS+PASS1_BITS+3)
2044 & RANGE_MASK];
2045 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
2046 CONST_BITS+PASS1_BITS+3)
2047 & RANGE_MASK];
2048 outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
2049 CONST_BITS+PASS1_BITS+3)
2050 & RANGE_MASK];
2051 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
2052 CONST_BITS+PASS1_BITS+3)
2053 & RANGE_MASK];
2054 outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
2055 CONST_BITS+PASS1_BITS+3)
2056 & RANGE_MASK];
2057 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
2058 CONST_BITS+PASS1_BITS+3)
2059 & RANGE_MASK];
2060 outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
2061 CONST_BITS+PASS1_BITS+3)
2062 & RANGE_MASK];
2063 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
2064 CONST_BITS+PASS1_BITS+3)
2065 & RANGE_MASK];
2066 outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
2067 CONST_BITS+PASS1_BITS+3)
2068 & RANGE_MASK];
2069 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp15,
2070 CONST_BITS+PASS1_BITS+3)
2071 & RANGE_MASK];
2072 outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp15,
2073 CONST_BITS+PASS1_BITS+3)
2074 & RANGE_MASK];
2075 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp26,
2076 CONST_BITS+PASS1_BITS+3)
2077 & RANGE_MASK];
2078
2079 wsptr += 8; /* advance pointer to next row */
2080 }
2081 }
2082
2083
2084 /*
2085 * Perform dequantization and inverse DCT on one block of coefficients,
2086 * producing a 14x14 output block.
2087 *
2088 * Optimized algorithm with 20 multiplications in the 1-D kernel.
2089 * cK represents sqrt(2) * cos(K*pi/28).
2090 */
2091
2092 GLOBAL(void)
2093 jpeg_idct_14x14 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
2094 JCOEFPTR coef_block,
2095 JSAMPARRAY output_buf, JDIMENSION output_col)
2096 {
2097 INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15, tmp16;
2098 INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26;
2099 INT32 z1, z2, z3, z4;
2100 JCOEFPTR inptr;
2101 ISLOW_MULT_TYPE * quantptr;
2102 int * wsptr;
2103 JSAMPROW outptr;
2104 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
2105 int ctr;
2106 int workspace[8*14]; /* buffers data between passes */
2107 SHIFT_TEMPS
2108
2109 /* Pass 1: process columns from input, store into work array. */
2110
2111 inptr = coef_block;
2112 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
2113 wsptr = workspace;
2114 for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
2115 /* Even part */
2116
2117 z1 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
2118 z1 <<= CONST_BITS;
2119 /* Add fudge factor here for final descale. */
2120 z1 += ONE << (CONST_BITS-PASS1_BITS-1);
2121 z4 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
2122 z2 = MULTIPLY(z4, FIX(1.274162392)); /* c4 */
2123 z3 = MULTIPLY(z4, FIX(0.314692123)); /* c12 */
2124 z4 = MULTIPLY(z4, FIX(0.881747734)); /* c8 */
2125
2126 tmp10 = z1 + z2;
2127 tmp11 = z1 + z3;
2128 tmp12 = z1 - z4;
2129
2130 tmp23 = RIGHT_SHIFT(z1 - ((z2 + z3 - z4) << 1), /* c0 = (c4+c12-c8)*2 */
2131 CONST_BITS-PASS1_BITS);
2132
2133 z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
2134 z2 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
2135
2136 z3 = MULTIPLY(z1 + z2, FIX(1.105676686)); /* c6 */
2137
2138 tmp13 = z3 + MULTIPLY(z1, FIX(0.273079590)); /* c2-c6 */
2139 tmp14 = z3 - MULTIPLY(z2, FIX(1.719280954)); /* c6+c10 */
2140 tmp15 = MULTIPLY(z1, FIX(0.613604268)) - /* c10 */
2141 MULTIPLY(z2, FIX(1.378756276)); /* c2 */
2142
2143 tmp20 = tmp10 + tmp13;
2144 tmp26 = tmp10 - tmp13;
2145 tmp21 = tmp11 + tmp14;
2146 tmp25 = tmp11 - tmp14;
2147 tmp22 = tmp12 + tmp15;
2148 tmp24 = tmp12 - tmp15;
2149
2150 /* Odd part */
2151
2152 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
2153 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
2154 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
2155 z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
2156 tmp13 = z4 << CONST_BITS;
2157
2158 tmp14 = z1 + z3;
2159 tmp11 = MULTIPLY(z1 + z2, FIX(1.334852607)); /* c3 */
2160 tmp12 = MULTIPLY(tmp14, FIX(1.197448846)); /* c5 */
2161 tmp10 = tmp11 + tmp12 + tmp13 - MULTIPLY(z1, FIX(1.126980169)); /* c3+c5-c1 */
2162 tmp14 = MULTIPLY(tmp14, FIX(0.752406978)); /* c9 */
2163 tmp16 = tmp14 - MULTIPLY(z1, FIX(1.061150426)); /* c9+c11-c13 */
2164 z1 -= z2;
2165 tmp15 = MULTIPLY(z1, FIX(0.467085129)) - tmp13; /* c11 */
2166 tmp16 += tmp15;
2167 z1 += z4;
2168 z4 = MULTIPLY(z2 + z3, - FIX(0.158341681)) - tmp13; /* -c13 */
2169 tmp11 += z4 - MULTIPLY(z2, FIX(0.424103948)); /* c3-c9-c13 */
2170 tmp12 += z4 - MULTIPLY(z3, FIX(2.373959773)); /* c3+c5-c13 */
2171 z4 = MULTIPLY(z3 - z2, FIX(1.405321284)); /* c1 */
2172 tmp14 += z4 + tmp13 - MULTIPLY(z3, FIX(1.6906431334)); /* c1+c9-c11 */
2173 tmp15 += z4 + MULTIPLY(z2, FIX(0.674957567)); /* c1+c11-c5 */
2174
2175 tmp13 = (z1 - z3) << PASS1_BITS;
2176
2177 /* Final output stage */
2178
2179 wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
2180 wsptr[8*13] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
2181 wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
2182 wsptr[8*12] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
2183 wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
2184 wsptr[8*11] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
2185 wsptr[8*3] = (int) (tmp23 + tmp13);
2186 wsptr[8*10] = (int) (tmp23 - tmp13);
2187 wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
2188 wsptr[8*9] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
2189 wsptr[8*5] = (int) RIGHT_SHIFT(tmp25 + tmp15, CONST_BITS-PASS1_BITS);
2190 wsptr[8*8] = (int) RIGHT_SHIFT(tmp25 - tmp15, CONST_BITS-PASS1_BITS);
2191 wsptr[8*6] = (int) RIGHT_SHIFT(tmp26 + tmp16, CONST_BITS-PASS1_BITS);
2192 wsptr[8*7] = (int) RIGHT_SHIFT(tmp26 - tmp16, CONST_BITS-PASS1_BITS);
2193 }
2194
2195 /* Pass 2: process 14 rows from work array, store into output array. */
2196
2197 wsptr = workspace;
2198 for (ctr = 0; ctr < 14; ctr++) {
2199 outptr = output_buf[ctr] + output_col;
2200
2201 /* Even part */
2202
2203 /* Add fudge factor here for final descale. */
2204 z1 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
2205 z1 <<= CONST_BITS;
2206 z4 = (INT32) wsptr[4];
2207 z2 = MULTIPLY(z4, FIX(1.274162392)); /* c4 */
2208 z3 = MULTIPLY(z4, FIX(0.314692123)); /* c12 */
2209 z4 = MULTIPLY(z4, FIX(0.881747734)); /* c8 */
2210
2211 tmp10 = z1 + z2;
2212 tmp11 = z1 + z3;
2213 tmp12 = z1 - z4;
2214
2215 tmp23 = z1 - ((z2 + z3 - z4) << 1); /* c0 = (c4+c12-c8)*2 */
2216
2217 z1 = (INT32) wsptr[2];
2218 z2 = (INT32) wsptr[6];
2219
2220 z3 = MULTIPLY(z1 + z2, FIX(1.105676686)); /* c6 */
2221
2222 tmp13 = z3 + MULTIPLY(z1, FIX(0.273079590)); /* c2-c6 */
2223 tmp14 = z3 - MULTIPLY(z2, FIX(1.719280954)); /* c6+c10 */
2224 tmp15 = MULTIPLY(z1, FIX(0.613604268)) - /* c10 */
2225 MULTIPLY(z2, FIX(1.378756276)); /* c2 */
2226
2227 tmp20 = tmp10 + tmp13;
2228 tmp26 = tmp10 - tmp13;
2229 tmp21 = tmp11 + tmp14;
2230 tmp25 = tmp11 - tmp14;
2231 tmp22 = tmp12 + tmp15;
2232 tmp24 = tmp12 - tmp15;
2233
2234 /* Odd part */
2235
2236 z1 = (INT32) wsptr[1];
2237 z2 = (INT32) wsptr[3];
2238 z3 = (INT32) wsptr[5];
2239 z4 = (INT32) wsptr[7];
2240 z4 <<= CONST_BITS;
2241
2242 tmp14 = z1 + z3;
2243 tmp11 = MULTIPLY(z1 + z2, FIX(1.334852607)); /* c3 */
2244 tmp12 = MULTIPLY(tmp14, FIX(1.197448846)); /* c5 */
2245 tmp10 = tmp11 + tmp12 + z4 - MULTIPLY(z1, FIX(1.126980169)); /* c3+c5-c1 */
2246 tmp14 = MULTIPLY(tmp14, FIX(0.752406978)); /* c9 */
2247 tmp16 = tmp14 - MULTIPLY(z1, FIX(1.061150426)); /* c9+c11-c13 */
2248 z1 -= z2;
2249 tmp15 = MULTIPLY(z1, FIX(0.467085129)) - z4; /* c11 */
2250 tmp16 += tmp15;
2251 tmp13 = MULTIPLY(z2 + z3, - FIX(0.158341681)) - z4; /* -c13 */
2252 tmp11 += tmp13 - MULTIPLY(z2, FIX(0.424103948)); /* c3-c9-c13 */
2253 tmp12 += tmp13 - MULTIPLY(z3, FIX(2.373959773)); /* c3+c5-c13 */
2254 tmp13 = MULTIPLY(z3 - z2, FIX(1.405321284)); /* c1 */
2255 tmp14 += tmp13 + z4 - MULTIPLY(z3, FIX(1.6906431334)); /* c1+c9-c11 */
2256 tmp15 += tmp13 + MULTIPLY(z2, FIX(0.674957567)); /* c1+c11-c5 */
2257
2258 tmp13 = ((z1 - z3) << CONST_BITS) + z4;
2259
2260 /* Final output stage */
2261
2262 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
2263 CONST_BITS+PASS1_BITS+3)
2264 & RANGE_MASK];
2265 outptr[13] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
2266 CONST_BITS+PASS1_BITS+3)
2267 & RANGE_MASK];
2268 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
2269 CONST_BITS+PASS1_BITS+3)
2270 & RANGE_MASK];
2271 outptr[12] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
2272 CONST_BITS+PASS1_BITS+3)
2273 & RANGE_MASK];
2274 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
2275 CONST_BITS+PASS1_BITS+3)
2276 & RANGE_MASK];
2277 outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
2278 CONST_BITS+PASS1_BITS+3)
2279 & RANGE_MASK];
2280 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
2281 CONST_BITS+PASS1_BITS+3)
2282 & RANGE_MASK];
2283 outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
2284 CONST_BITS+PASS1_BITS+3)
2285 & RANGE_MASK];
2286 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
2287 CONST_BITS+PASS1_BITS+3)
2288 & RANGE_MASK];
2289 outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
2290 CONST_BITS+PASS1_BITS+3)
2291 & RANGE_MASK];
2292 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp15,
2293 CONST_BITS+PASS1_BITS+3)
2294 & RANGE_MASK];
2295 outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp15,
2296 CONST_BITS+PASS1_BITS+3)
2297 & RANGE_MASK];
2298 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp26 + tmp16,
2299 CONST_BITS+PASS1_BITS+3)
2300 & RANGE_MASK];
2301 outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp26 - tmp16,
2302 CONST_BITS+PASS1_BITS+3)
2303 & RANGE_MASK];
2304
2305 wsptr += 8; /* advance pointer to next row */
2306 }
2307 }
2308
2309
2310 /*
2311 * Perform dequantization and inverse DCT on one block of coefficients,
2312 * producing a 15x15 output block.
2313 *
2314 * Optimized algorithm with 22 multiplications in the 1-D kernel.
2315 * cK represents sqrt(2) * cos(K*pi/30).
2316 */
2317
2318 GLOBAL(void)
2319 jpeg_idct_15x15 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
2320 JCOEFPTR coef_block,
2321 JSAMPARRAY output_buf, JDIMENSION output_col)
2322 {
2323 INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15, tmp16;
2324 INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26, tmp27;
2325 INT32 z1, z2, z3, z4;
2326 JCOEFPTR inptr;
2327 ISLOW_MULT_TYPE * quantptr;
2328 int * wsptr;
2329 JSAMPROW outptr;
2330 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
2331 int ctr;
2332 int workspace[8*15]; /* buffers data between passes */
2333 SHIFT_TEMPS
2334
2335 /* Pass 1: process columns from input, store into work array. */
2336
2337 inptr = coef_block;
2338 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
2339 wsptr = workspace;
2340 for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
2341 /* Even part */
2342
2343 z1 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
2344 z1 <<= CONST_BITS;
2345 /* Add fudge factor here for final descale. */
2346 z1 += ONE << (CONST_BITS-PASS1_BITS-1);
2347
2348 z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
2349 z3 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
2350 z4 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
2351
2352 tmp10 = MULTIPLY(z4, FIX(0.437016024)); /* c12 */
2353 tmp11 = MULTIPLY(z4, FIX(1.144122806)); /* c6 */
2354
2355 tmp12 = z1 - tmp10;
2356 tmp13 = z1 + tmp11;
2357 z1 -= (tmp11 - tmp10) << 1; /* c0 = (c6-c12)*2 */
2358
2359 z4 = z2 - z3;
2360 z3 += z2;
2361 tmp10 = MULTIPLY(z3, FIX(1.337628990)); /* (c2+c4)/2 */
2362 tmp11 = MULTIPLY(z4, FIX(0.045680613)); /* (c2-c4)/2 */
2363 z2 = MULTIPLY(z2, FIX(1.439773946)); /* c4+c14 */
2364
2365 tmp20 = tmp13 + tmp10 + tmp11;
2366 tmp23 = tmp12 - tmp10 + tmp11 + z2;
2367
2368 tmp10 = MULTIPLY(z3, FIX(0.547059574)); /* (c8+c14)/2 */
2369 tmp11 = MULTIPLY(z4, FIX(0.399234004)); /* (c8-c14)/2 */
2370
2371 tmp25 = tmp13 - tmp10 - tmp11;
2372 tmp26 = tmp12 + tmp10 - tmp11 - z2;
2373
2374 tmp10 = MULTIPLY(z3, FIX(0.790569415)); /* (c6+c12)/2 */
2375 tmp11 = MULTIPLY(z4, FIX(0.353553391)); /* (c6-c12)/2 */
2376
2377 tmp21 = tmp12 + tmp10 + tmp11;
2378 tmp24 = tmp13 - tmp10 + tmp11;
2379 tmp11 += tmp11;
2380 tmp22 = z1 + tmp11; /* c10 = c6-c12 */
2381 tmp27 = z1 - tmp11 - tmp11; /* c0 = (c6-c12)*2 */
2382
2383 /* Odd part */
2384
2385 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
2386 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
2387 z4 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
2388 z3 = MULTIPLY(z4, FIX(1.224744871)); /* c5 */
2389 z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
2390
2391 tmp13 = z2 - z4;
2392 tmp15 = MULTIPLY(z1 + tmp13, FIX(0.831253876)); /* c9 */
2393 tmp11 = tmp15 + MULTIPLY(z1, FIX(0.513743148)); /* c3-c9 */
2394 tmp14 = tmp15 - MULTIPLY(tmp13, FIX(2.176250899)); /* c3+c9 */
2395
2396 tmp13 = MULTIPLY(z2, - FIX(0.831253876)); /* -c9 */
2397 tmp15 = MULTIPLY(z2, - FIX(1.344997024)); /* -c3 */
2398 z2 = z1 - z4;
2399 tmp12 = z3 + MULTIPLY(z2, FIX(1.406466353)); /* c1 */
2400
2401 tmp10 = tmp12 + MULTIPLY(z4, FIX(2.457431844)) - tmp15; /* c1+c7 */
2402 tmp16 = tmp12 - MULTIPLY(z1, FIX(1.112434820)) + tmp13; /* c1-c13 */
2403 tmp12 = MULTIPLY(z2, FIX(1.224744871)) - z3; /* c5 */
2404 z2 = MULTIPLY(z1 + z4, FIX(0.575212477)); /* c11 */
2405 tmp13 += z2 + MULTIPLY(z1, FIX(0.475753014)) - z3; /* c7-c11 */
2406 tmp15 += z2 - MULTIPLY(z4, FIX(0.869244010)) + z3; /* c11+c13 */
2407
2408 /* Final output stage */
2409
2410 wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
2411 wsptr[8*14] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
2412 wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
2413 wsptr[8*13] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
2414 wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
2415 wsptr[8*12] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
2416 wsptr[8*3] = (int) RIGHT_SHIFT(tmp23 + tmp13, CONST_BITS-PASS1_BITS);
2417 wsptr[8*11] = (int) RIGHT_SHIFT(tmp23 - tmp13, CONST_BITS-PASS1_BITS);
2418 wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
2419 wsptr[8*10] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
2420 wsptr[8*5] = (int) RIGHT_SHIFT(tmp25 + tmp15, CONST_BITS-PASS1_BITS);
2421 wsptr[8*9] = (int) RIGHT_SHIFT(tmp25 - tmp15, CONST_BITS-PASS1_BITS);
2422 wsptr[8*6] = (int) RIGHT_SHIFT(tmp26 + tmp16, CONST_BITS-PASS1_BITS);
2423 wsptr[8*8] = (int) RIGHT_SHIFT(tmp26 - tmp16, CONST_BITS-PASS1_BITS);
2424 wsptr[8*7] = (int) RIGHT_SHIFT(tmp27, CONST_BITS-PASS1_BITS);
2425 }
2426
2427 /* Pass 2: process 15 rows from work array, store into output array. */
2428
2429 wsptr = workspace;
2430 for (ctr = 0; ctr < 15; ctr++) {
2431 outptr = output_buf[ctr] + output_col;
2432
2433 /* Even part */
2434
2435 /* Add fudge factor here for final descale. */
2436 z1 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
2437 z1 <<= CONST_BITS;
2438
2439 z2 = (INT32) wsptr[2];
2440 z3 = (INT32) wsptr[4];
2441 z4 = (INT32) wsptr[6];
2442
2443 tmp10 = MULTIPLY(z4, FIX(0.437016024)); /* c12 */
2444 tmp11 = MULTIPLY(z4, FIX(1.144122806)); /* c6 */
2445
2446 tmp12 = z1 - tmp10;
2447 tmp13 = z1 + tmp11;
2448 z1 -= (tmp11 - tmp10) << 1; /* c0 = (c6-c12)*2 */
2449
2450 z4 = z2 - z3;
2451 z3 += z2;
2452 tmp10 = MULTIPLY(z3, FIX(1.337628990)); /* (c2+c4)/2 */
2453 tmp11 = MULTIPLY(z4, FIX(0.045680613)); /* (c2-c4)/2 */
2454 z2 = MULTIPLY(z2, FIX(1.439773946)); /* c4+c14 */
2455
2456 tmp20 = tmp13 + tmp10 + tmp11;
2457 tmp23 = tmp12 - tmp10 + tmp11 + z2;
2458
2459 tmp10 = MULTIPLY(z3, FIX(0.547059574)); /* (c8+c14)/2 */
2460 tmp11 = MULTIPLY(z4, FIX(0.399234004)); /* (c8-c14)/2 */
2461
2462 tmp25 = tmp13 - tmp10 - tmp11;
2463 tmp26 = tmp12 + tmp10 - tmp11 - z2;
2464
2465 tmp10 = MULTIPLY(z3, FIX(0.790569415)); /* (c6+c12)/2 */
2466 tmp11 = MULTIPLY(z4, FIX(0.353553391)); /* (c6-c12)/2 */
2467
2468 tmp21 = tmp12 + tmp10 + tmp11;
2469 tmp24 = tmp13 - tmp10 + tmp11;
2470 tmp11 += tmp11;
2471 tmp22 = z1 + tmp11; /* c10 = c6-c12 */
2472 tmp27 = z1 - tmp11 - tmp11; /* c0 = (c6-c12)*2 */
2473
2474 /* Odd part */
2475
2476 z1 = (INT32) wsptr[1];
2477 z2 = (INT32) wsptr[3];
2478 z4 = (INT32) wsptr[5];
2479 z3 = MULTIPLY(z4, FIX(1.224744871)); /* c5 */
2480 z4 = (INT32) wsptr[7];
2481
2482 tmp13 = z2 - z4;
2483 tmp15 = MULTIPLY(z1 + tmp13, FIX(0.831253876)); /* c9 */
2484 tmp11 = tmp15 + MULTIPLY(z1, FIX(0.513743148)); /* c3-c9 */
2485 tmp14 = tmp15 - MULTIPLY(tmp13, FIX(2.176250899)); /* c3+c9 */
2486
2487 tmp13 = MULTIPLY(z2, - FIX(0.831253876)); /* -c9 */
2488 tmp15 = MULTIPLY(z2, - FIX(1.344997024)); /* -c3 */
2489 z2 = z1 - z4;
2490 tmp12 = z3 + MULTIPLY(z2, FIX(1.406466353)); /* c1 */
2491
2492 tmp10 = tmp12 + MULTIPLY(z4, FIX(2.457431844)) - tmp15; /* c1+c7 */
2493 tmp16 = tmp12 - MULTIPLY(z1, FIX(1.112434820)) + tmp13; /* c1-c13 */
2494 tmp12 = MULTIPLY(z2, FIX(1.224744871)) - z3; /* c5 */
2495 z2 = MULTIPLY(z1 + z4, FIX(0.575212477)); /* c11 */
2496 tmp13 += z2 + MULTIPLY(z1, FIX(0.475753014)) - z3; /* c7-c11 */
2497 tmp15 += z2 - MULTIPLY(z4, FIX(0.869244010)) + z3; /* c11+c13 */
2498
2499 /* Final output stage */
2500
2501 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
2502 CONST_BITS+PASS1_BITS+3)
2503 & RANGE_MASK];
2504 outptr[14] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
2505 CONST_BITS+PASS1_BITS+3)
2506 & RANGE_MASK];
2507 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
2508 CONST_BITS+PASS1_BITS+3)
2509 & RANGE_MASK];
2510 outptr[13] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
2511 CONST_BITS+PASS1_BITS+3)
2512 & RANGE_MASK];
2513 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
2514 CONST_BITS+PASS1_BITS+3)
2515 & RANGE_MASK];
2516 outptr[12] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
2517 CONST_BITS+PASS1_BITS+3)
2518 & RANGE_MASK];
2519 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
2520 CONST_BITS+PASS1_BITS+3)
2521 & RANGE_MASK];
2522 outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
2523 CONST_BITS+PASS1_BITS+3)
2524 & RANGE_MASK];
2525 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
2526 CONST_BITS+PASS1_BITS+3)
2527 & RANGE_MASK];
2528 outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
2529 CONST_BITS+PASS1_BITS+3)
2530 & RANGE_MASK];
2531 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp15,
2532 CONST_BITS+PASS1_BITS+3)
2533 & RANGE_MASK];
2534 outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp15,
2535 CONST_BITS+PASS1_BITS+3)
2536 & RANGE_MASK];
2537 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp26 + tmp16,
2538 CONST_BITS+PASS1_BITS+3)
2539 & RANGE_MASK];
2540 outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp26 - tmp16,
2541 CONST_BITS+PASS1_BITS+3)
2542 & RANGE_MASK];
2543 outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp27,
2544 CONST_BITS+PASS1_BITS+3)
2545 & RANGE_MASK];
2546
2547 wsptr += 8; /* advance pointer to next row */
2548 }
2549 }
2550
2551
2552 /*
2553 * Perform dequantization and inverse DCT on one block of coefficients,
2554 * producing a 16x16 output block.
2555 *
2556 * Optimized algorithm with 28 multiplications in the 1-D kernel.
2557 * cK represents sqrt(2) * cos(K*pi/32).
2558 */
2559
2560 GLOBAL(void)
2561 jpeg_idct_16x16 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
2562 JCOEFPTR coef_block,
2563 JSAMPARRAY output_buf, JDIMENSION output_col)
2564 {
2565 INT32 tmp0, tmp1, tmp2, tmp3, tmp10, tmp11, tmp12, tmp13;
2566 INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26, tmp27;
2567 INT32 z1, z2, z3, z4;
2568 JCOEFPTR inptr;
2569 ISLOW_MULT_TYPE * quantptr;
2570 int * wsptr;
2571 JSAMPROW outptr;
2572 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
2573 int ctr;
2574 int workspace[8*16]; /* buffers data between passes */
2575 SHIFT_TEMPS
2576
2577 /* Pass 1: process columns from input, store into work array. */
2578
2579 inptr = coef_block;
2580 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
2581 wsptr = workspace;
2582 for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
2583 /* Even part */
2584
2585 tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
2586 tmp0 <<= CONST_BITS;
2587 /* Add fudge factor here for final descale. */
2588 tmp0 += 1 << (CONST_BITS-PASS1_BITS-1);
2589
2590 z1 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
2591 tmp1 = MULTIPLY(z1, FIX(1.306562965)); /* c4[16] = c2[8] */
2592 tmp2 = MULTIPLY(z1, FIX_0_541196100); /* c12[16] = c6[8] */
2593
2594 tmp10 = tmp0 + tmp1;
2595 tmp11 = tmp0 - tmp1;
2596 tmp12 = tmp0 + tmp2;
2597 tmp13 = tmp0 - tmp2;
2598
2599 z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
2600 z2 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
2601 z3 = z1 - z2;
2602 z4 = MULTIPLY(z3, FIX(0.275899379)); /* c14[16] = c7[8] */
2603 z3 = MULTIPLY(z3, FIX(1.387039845)); /* c2[16] = c1[8] */
2604
2605 tmp0 = z3 + MULTIPLY(z2, FIX_2_562915447); /* (c6+c2)[16] = (c3+c1)[8] */
2606 tmp1 = z4 + MULTIPLY(z1, FIX_0_899976223); /* (c6-c14)[16] = (c3-c7)[8] */
2607 tmp2 = z3 - MULTIPLY(z1, FIX(0.601344887)); /* (c2-c10)[16] = (c1-c5)[8] */
2608 tmp3 = z4 - MULTIPLY(z2, FIX(0.509795579)); /* (c10-c14)[16] = (c5-c7)[8] */
2609
2610 tmp20 = tmp10 + tmp0;
2611 tmp27 = tmp10 - tmp0;
2612 tmp21 = tmp12 + tmp1;
2613 tmp26 = tmp12 - tmp1;
2614 tmp22 = tmp13 + tmp2;
2615 tmp25 = tmp13 - tmp2;
2616 tmp23 = tmp11 + tmp3;
2617 tmp24 = tmp11 - tmp3;
2618
2619 /* Odd part */
2620
2621 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
2622 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
2623 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
2624 z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
2625
2626 tmp11 = z1 + z3;
2627
2628 tmp1 = MULTIPLY(z1 + z2, FIX(1.353318001)); /* c3 */
2629 tmp2 = MULTIPLY(tmp11, FIX(1.247225013)); /* c5 */
2630 tmp3 = MULTIPLY(z1 + z4, FIX(1.093201867)); /* c7 */
2631 tmp10 = MULTIPLY(z1 - z4, FIX(0.897167586)); /* c9 */
2632 tmp11 = MULTIPLY(tmp11, FIX(0.666655658)); /* c11 */
2633 tmp12 = MULTIPLY(z1 - z2, FIX(0.410524528)); /* c13 */
2634 tmp0 = tmp1 + tmp2 + tmp3 -
2635 MULTIPLY(z1, FIX(2.286341144)); /* c7+c5+c3-c1 */
2636 tmp13 = tmp10 + tmp11 + tmp12 -
2637 MULTIPLY(z1, FIX(1.835730603)); /* c9+c11+c13-c15 */
2638 z1 = MULTIPLY(z2 + z3, FIX(0.138617169)); /* c15 */
2639 tmp1 += z1 + MULTIPLY(z2, FIX(0.071888074)); /* c9+c11-c3-c15 */
2640 tmp2 += z1 - MULTIPLY(z3, FIX(1.125726048)); /* c5+c7+c15-c3 */
2641 z1 = MULTIPLY(z3 - z2, FIX(1.407403738)); /* c1 */
2642 tmp11 += z1 - MULTIPLY(z3, FIX(0.766367282)); /* c1+c11-c9-c13 */
2643 tmp12 += z1 + MULTIPLY(z2, FIX(1.971951411)); /* c1+c5+c13-c7 */
2644 z2 += z4;
2645 z1 = MULTIPLY(z2, - FIX(0.666655658)); /* -c11 */
2646 tmp1 += z1;
2647 tmp3 += z1 + MULTIPLY(z4, FIX(1.065388962)); /* c3+c11+c15-c7 */
2648 z2 = MULTIPLY(z2, - FIX(1.247225013)); /* -c5 */
2649 tmp10 += z2 + MULTIPLY(z4, FIX(3.141271809)); /* c1+c5+c9-c13 */
2650 tmp12 += z2;
2651 z2 = MULTIPLY(z3 + z4, - FIX(1.353318001)); /* -c3 */
2652 tmp2 += z2;
2653 tmp3 += z2;
2654 z2 = MULTIPLY(z4 - z3, FIX(0.410524528)); /* c13 */
2655 tmp10 += z2;
2656 tmp11 += z2;
2657
2658 /* Final output stage */
2659
2660 wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp0, CONST_BITS-PASS1_BITS);
2661 wsptr[8*15] = (int) RIGHT_SHIFT(tmp20 - tmp0, CONST_BITS-PASS1_BITS);
2662 wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp1, CONST_BITS-PASS1_BITS);
2663 wsptr[8*14] = (int) RIGHT_SHIFT(tmp21 - tmp1, CONST_BITS-PASS1_BITS);
2664 wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp2, CONST_BITS-PASS1_BITS);
2665 wsptr[8*13] = (int) RIGHT_SHIFT(tmp22 - tmp2, CONST_BITS-PASS1_BITS);
2666 wsptr[8*3] = (int) RIGHT_SHIFT(tmp23 + tmp3, CONST_BITS-PASS1_BITS);
2667 wsptr[8*12] = (int) RIGHT_SHIFT(tmp23 - tmp3, CONST_BITS-PASS1_BITS);
2668 wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp10, CONST_BITS-PASS1_BITS);
2669 wsptr[8*11] = (int) RIGHT_SHIFT(tmp24 - tmp10, CONST_BITS-PASS1_BITS);
2670 wsptr[8*5] = (int) RIGHT_SHIFT(tmp25 + tmp11, CONST_BITS-PASS1_BITS);
2671 wsptr[8*10] = (int) RIGHT_SHIFT(tmp25 - tmp11, CONST_BITS-PASS1_BITS);
2672 wsptr[8*6] = (int) RIGHT_SHIFT(tmp26 + tmp12, CONST_BITS-PASS1_BITS);
2673 wsptr[8*9] = (int) RIGHT_SHIFT(tmp26 - tmp12, CONST_BITS-PASS1_BITS);
2674 wsptr[8*7] = (int) RIGHT_SHIFT(tmp27 + tmp13, CONST_BITS-PASS1_BITS);
2675 wsptr[8*8] = (int) RIGHT_SHIFT(tmp27 - tmp13, CONST_BITS-PASS1_BITS);
2676 }
2677
2678 /* Pass 2: process 16 rows from work array, store into output array. */
2679
2680 wsptr = workspace;
2681 for (ctr = 0; ctr < 16; ctr++) {
2682 outptr = output_buf[ctr] + output_col;
2683
2684 /* Even part */
2685
2686 /* Add fudge factor here for final descale. */
2687 tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
2688 tmp0 <<= CONST_BITS;
2689
2690 z1 = (INT32) wsptr[4];
2691 tmp1 = MULTIPLY(z1, FIX(1.306562965)); /* c4[16] = c2[8] */
2692 tmp2 = MULTIPLY(z1, FIX_0_541196100); /* c12[16] = c6[8] */
2693
2694 tmp10 = tmp0 + tmp1;
2695 tmp11 = tmp0 - tmp1;
2696 tmp12 = tmp0 + tmp2;
2697 tmp13 = tmp0 - tmp2;
2698
2699 z1 = (INT32) wsptr[2];
2700 z2 = (INT32) wsptr[6];
2701 z3 = z1 - z2;
2702 z4 = MULTIPLY(z3, FIX(0.275899379)); /* c14[16] = c7[8] */
2703 z3 = MULTIPLY(z3, FIX(1.387039845)); /* c2[16] = c1[8] */
2704
2705 tmp0 = z3 + MULTIPLY(z2, FIX_2_562915447); /* (c6+c2)[16] = (c3+c1)[8] */
2706 tmp1 = z4 + MULTIPLY(z1, FIX_0_899976223); /* (c6-c14)[16] = (c3-c7)[8] */
2707 tmp2 = z3 - MULTIPLY(z1, FIX(0.601344887)); /* (c2-c10)[16] = (c1-c5)[8] */
2708 tmp3 = z4 - MULTIPLY(z2, FIX(0.509795579)); /* (c10-c14)[16] = (c5-c7)[8] */
2709
2710 tmp20 = tmp10 + tmp0;
2711 tmp27 = tmp10 - tmp0;
2712 tmp21 = tmp12 + tmp1;
2713 tmp26 = tmp12 - tmp1;
2714 tmp22 = tmp13 + tmp2;
2715 tmp25 = tmp13 - tmp2;
2716 tmp23 = tmp11 + tmp3;
2717 tmp24 = tmp11 - tmp3;
2718
2719 /* Odd part */
2720
2721 z1 = (INT32) wsptr[1];
2722 z2 = (INT32) wsptr[3];
2723 z3 = (INT32) wsptr[5];
2724 z4 = (INT32) wsptr[7];
2725
2726 tmp11 = z1 + z3;
2727
2728 tmp1 = MULTIPLY(z1 + z2, FIX(1.353318001)); /* c3 */
2729 tmp2 = MULTIPLY(tmp11, FIX(1.247225013)); /* c5 */
2730 tmp3 = MULTIPLY(z1 + z4, FIX(1.093201867)); /* c7 */
2731 tmp10 = MULTIPLY(z1 - z4, FIX(0.897167586)); /* c9 */
2732 tmp11 = MULTIPLY(tmp11, FIX(0.666655658)); /* c11 */
2733 tmp12 = MULTIPLY(z1 - z2, FIX(0.410524528)); /* c13 */
2734 tmp0 = tmp1 + tmp2 + tmp3 -
2735 MULTIPLY(z1, FIX(2.286341144)); /* c7+c5+c3-c1 */
2736 tmp13 = tmp10 + tmp11 + tmp12 -
2737 MULTIPLY(z1, FIX(1.835730603)); /* c9+c11+c13-c15 */
2738 z1 = MULTIPLY(z2 + z3, FIX(0.138617169)); /* c15 */
2739 tmp1 += z1 + MULTIPLY(z2, FIX(0.071888074)); /* c9+c11-c3-c15 */
2740 tmp2 += z1 - MULTIPLY(z3, FIX(1.125726048)); /* c5+c7+c15-c3 */
2741 z1 = MULTIPLY(z3 - z2, FIX(1.407403738)); /* c1 */
2742 tmp11 += z1 - MULTIPLY(z3, FIX(0.766367282)); /* c1+c11-c9-c13 */
2743 tmp12 += z1 + MULTIPLY(z2, FIX(1.971951411)); /* c1+c5+c13-c7 */
2744 z2 += z4;
2745 z1 = MULTIPLY(z2, - FIX(0.666655658)); /* -c11 */
2746 tmp1 += z1;
2747 tmp3 += z1 + MULTIPLY(z4, FIX(1.065388962)); /* c3+c11+c15-c7 */
2748 z2 = MULTIPLY(z2, - FIX(1.247225013)); /* -c5 */
2749 tmp10 += z2 + MULTIPLY(z4, FIX(3.141271809)); /* c1+c5+c9-c13 */
2750 tmp12 += z2;
2751 z2 = MULTIPLY(z3 + z4, - FIX(1.353318001)); /* -c3 */
2752 tmp2 += z2;
2753 tmp3 += z2;
2754 z2 = MULTIPLY(z4 - z3, FIX(0.410524528)); /* c13 */
2755 tmp10 += z2;
2756 tmp11 += z2;
2757
2758 /* Final output stage */
2759
2760 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp0,
2761 CONST_BITS+PASS1_BITS+3)
2762 & RANGE_MASK];
2763 outptr[15] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp0,
2764 CONST_BITS+PASS1_BITS+3)
2765 & RANGE_MASK];
2766 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp1,
2767 CONST_BITS+PASS1_BITS+3)
2768 & RANGE_MASK];
2769 outptr[14] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp1,
2770 CONST_BITS+PASS1_BITS+3)
2771 & RANGE_MASK];
2772 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp2,
2773 CONST_BITS+PASS1_BITS+3)
2774 & RANGE_MASK];
2775 outptr[13] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp2,
2776 CONST_BITS+PASS1_BITS+3)
2777 & RANGE_MASK];
2778 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp3,
2779 CONST_BITS+PASS1_BITS+3)
2780 & RANGE_MASK];
2781 outptr[12] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp3,
2782 CONST_BITS+PASS1_BITS+3)
2783 & RANGE_MASK];
2784 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp10,
2785 CONST_BITS+PASS1_BITS+3)
2786 & RANGE_MASK];
2787 outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp10,
2788 CONST_BITS+PASS1_BITS+3)
2789 & RANGE_MASK];
2790 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp11,
2791 CONST_BITS+PASS1_BITS+3)
2792 & RANGE_MASK];
2793 outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp11,
2794 CONST_BITS+PASS1_BITS+3)
2795 & RANGE_MASK];
2796 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp26 + tmp12,
2797 CONST_BITS+PASS1_BITS+3)
2798 & RANGE_MASK];
2799 outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp26 - tmp12,
2800 CONST_BITS+PASS1_BITS+3)
2801 & RANGE_MASK];
2802 outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp27 + tmp13,
2803 CONST_BITS+PASS1_BITS+3)
2804 & RANGE_MASK];
2805 outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp27 - tmp13,
2806 CONST_BITS+PASS1_BITS+3)
2807 & RANGE_MASK];
2808
2809 wsptr += 8; /* advance pointer to next row */
2810 }
2811 }
2812
2813
2814 /*
2815 * Perform dequantization and inverse DCT on one block of coefficients,
2816 * producing a 16x8 output block.
2817 *
2818 * 8-point IDCT in pass 1 (columns), 16-point in pass 2 (rows).
2819 */
2820
2821 GLOBAL(void)
2822 jpeg_idct_16x8 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
2823 JCOEFPTR coef_block,
2824 JSAMPARRAY output_buf, JDIMENSION output_col)
2825 {
2826 INT32 tmp0, tmp1, tmp2, tmp3, tmp10, tmp11, tmp12, tmp13;
2827 INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26, tmp27;
2828 INT32 z1, z2, z3, z4;
2829 JCOEFPTR inptr;
2830 ISLOW_MULT_TYPE * quantptr;
2831 int * wsptr;
2832 JSAMPROW outptr;
2833 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
2834 int ctr;
2835 int workspace[8*8]; /* buffers data between passes */
2836 SHIFT_TEMPS
2837
2838 /* Pass 1: process columns from input, store into work array. */
2839 /* Note results are scaled up by sqrt(8) compared to a true IDCT; */
2840 /* furthermore, we scale the results by 2**PASS1_BITS. */
2841
2842 inptr = coef_block;
2843 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
2844 wsptr = workspace;
2845 for (ctr = DCTSIZE; ctr > 0; ctr--) {
2846 /* Due to quantization, we will usually find that many of the input
2847 * coefficients are zero, especially the AC terms. We can exploit this
2848 * by short-circuiting the IDCT calculation for any column in which all
2849 * the AC terms are zero. In that case each output is equal to the
2850 * DC coefficient (with scale factor as needed).
2851 * With typical images and quantization tables, half or more of the
2852 * column DCT calculations can be simplified this way.
2853 */
2854
2855 if (inptr[DCTSIZE*1] == 0 && inptr[DCTSIZE*2] == 0 &&
2856 inptr[DCTSIZE*3] == 0 && inptr[DCTSIZE*4] == 0 &&
2857 inptr[DCTSIZE*5] == 0 && inptr[DCTSIZE*6] == 0 &&
2858 inptr[DCTSIZE*7] == 0) {
2859 /* AC terms all zero */
2860 int dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]) << PASS1_BITS;
2861
2862 wsptr[DCTSIZE*0] = dcval;
2863 wsptr[DCTSIZE*1] = dcval;
2864 wsptr[DCTSIZE*2] = dcval;
2865 wsptr[DCTSIZE*3] = dcval;
2866 wsptr[DCTSIZE*4] = dcval;
2867 wsptr[DCTSIZE*5] = dcval;
2868 wsptr[DCTSIZE*6] = dcval;
2869 wsptr[DCTSIZE*7] = dcval;
2870
2871 inptr++; /* advance pointers to next column */
2872 quantptr++;
2873 wsptr++;
2874 continue;
2875 }
2876
2877 /* Even part: reverse the even part of the forward DCT. */
2878 /* The rotator is sqrt(2)*c(-6). */
2879
2880 z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
2881 z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
2882
2883 z1 = MULTIPLY(z2 + z3, FIX_0_541196100);
2884 tmp2 = z1 + MULTIPLY(z2, FIX_0_765366865);
2885 tmp3 = z1 - MULTIPLY(z3, FIX_1_847759065);
2886
2887 z2 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
2888 z3 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
2889 z2 <<= CONST_BITS;
2890 z3 <<= CONST_BITS;
2891 /* Add fudge factor here for final descale. */
2892 z2 += ONE << (CONST_BITS-PASS1_BITS-1);
2893
2894 tmp0 = z2 + z3;
2895 tmp1 = z2 - z3;
2896
2897 tmp10 = tmp0 + tmp2;
2898 tmp13 = tmp0 - tmp2;
2899 tmp11 = tmp1 + tmp3;
2900 tmp12 = tmp1 - tmp3;
2901
2902 /* Odd part per figure 8; the matrix is unitary and hence its
2903 * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively.
2904 */
2905
2906 tmp0 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
2907 tmp1 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
2908 tmp2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
2909 tmp3 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
2910
2911 z2 = tmp0 + tmp2;
2912 z3 = tmp1 + tmp3;
2913
2914 z1 = MULTIPLY(z2 + z3, FIX_1_175875602); /* sqrt(2) * c3 */
2915 z2 = MULTIPLY(z2, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
2916 z3 = MULTIPLY(z3, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
2917 z2 += z1;
2918 z3 += z1;
2919
2920 z1 = MULTIPLY(tmp0 + tmp3, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */
2921 tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
2922 tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */
2923 tmp0 += z1 + z2;
2924 tmp3 += z1 + z3;
2925
2926 z1 = MULTIPLY(tmp1 + tmp2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
2927 tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
2928 tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
2929 tmp1 += z1 + z3;
2930 tmp2 += z1 + z2;
2931
2932 /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */
2933
2934 wsptr[DCTSIZE*0] = (int) RIGHT_SHIFT(tmp10 + tmp3, CONST_BITS-PASS1_BITS);
2935 wsptr[DCTSIZE*7] = (int) RIGHT_SHIFT(tmp10 - tmp3, CONST_BITS-PASS1_BITS);
2936 wsptr[DCTSIZE*1] = (int) RIGHT_SHIFT(tmp11 + tmp2, CONST_BITS-PASS1_BITS);
2937 wsptr[DCTSIZE*6] = (int) RIGHT_SHIFT(tmp11 - tmp2, CONST_BITS-PASS1_BITS);
2938 wsptr[DCTSIZE*2] = (int) RIGHT_SHIFT(tmp12 + tmp1, CONST_BITS-PASS1_BITS);
2939 wsptr[DCTSIZE*5] = (int) RIGHT_SHIFT(tmp12 - tmp1, CONST_BITS-PASS1_BITS);
2940 wsptr[DCTSIZE*3] = (int) RIGHT_SHIFT(tmp13 + tmp0, CONST_BITS-PASS1_BITS);
2941 wsptr[DCTSIZE*4] = (int) RIGHT_SHIFT(tmp13 - tmp0, CONST_BITS-PASS1_BITS);
2942
2943 inptr++; /* advance pointers to next column */
2944 quantptr++;
2945 wsptr++;
2946 }
2947
2948 /* Pass 2: process 8 rows from work array, store into output array.
2949 * 16-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/32).
2950 */
2951 wsptr = workspace;
2952 for (ctr = 0; ctr < 8; ctr++) {
2953 outptr = output_buf[ctr] + output_col;
2954
2955 /* Even part */
2956
2957 /* Add fudge factor here for final descale. */
2958 tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
2959 tmp0 <<= CONST_BITS;
2960
2961 z1 = (INT32) wsptr[4];
2962 tmp1 = MULTIPLY(z1, FIX(1.306562965)); /* c4[16] = c2[8] */
2963 tmp2 = MULTIPLY(z1, FIX_0_541196100); /* c12[16] = c6[8] */
2964
2965 tmp10 = tmp0 + tmp1;
2966 tmp11 = tmp0 - tmp1;
2967 tmp12 = tmp0 + tmp2;
2968 tmp13 = tmp0 - tmp2;
2969
2970 z1 = (INT32) wsptr[2];
2971 z2 = (INT32) wsptr[6];
2972 z3 = z1 - z2;
2973 z4 = MULTIPLY(z3, FIX(0.275899379)); /* c14[16] = c7[8] */
2974 z3 = MULTIPLY(z3, FIX(1.387039845)); /* c2[16] = c1[8] */
2975
2976 tmp0 = z3 + MULTIPLY(z2, FIX_2_562915447); /* (c6+c2)[16] = (c3+c1)[8] */
2977 tmp1 = z4 + MULTIPLY(z1, FIX_0_899976223); /* (c6-c14)[16] = (c3-c7)[8] */
2978 tmp2 = z3 - MULTIPLY(z1, FIX(0.601344887)); /* (c2-c10)[16] = (c1-c5)[8] */
2979 tmp3 = z4 - MULTIPLY(z2, FIX(0.509795579)); /* (c10-c14)[16] = (c5-c7)[8] */
2980
2981 tmp20 = tmp10 + tmp0;
2982 tmp27 = tmp10 - tmp0;
2983 tmp21 = tmp12 + tmp1;
2984 tmp26 = tmp12 - tmp1;
2985 tmp22 = tmp13 + tmp2;
2986 tmp25 = tmp13 - tmp2;
2987 tmp23 = tmp11 + tmp3;
2988 tmp24 = tmp11 - tmp3;
2989
2990 /* Odd part */
2991
2992 z1 = (INT32) wsptr[1];
2993 z2 = (INT32) wsptr[3];
2994 z3 = (INT32) wsptr[5];
2995 z4 = (INT32) wsptr[7];
2996
2997 tmp11 = z1 + z3;
2998
2999 tmp1 = MULTIPLY(z1 + z2, FIX(1.353318001)); /* c3 */
3000 tmp2 = MULTIPLY(tmp11, FIX(1.247225013)); /* c5 */
3001 tmp3 = MULTIPLY(z1 + z4, FIX(1.093201867)); /* c7 */
3002 tmp10 = MULTIPLY(z1 - z4, FIX(0.897167586)); /* c9 */
3003 tmp11 = MULTIPLY(tmp11, FIX(0.666655658)); /* c11 */
3004 tmp12 = MULTIPLY(z1 - z2, FIX(0.410524528)); /* c13 */
3005 tmp0 = tmp1 + tmp2 + tmp3 -
3006 MULTIPLY(z1, FIX(2.286341144)); /* c7+c5+c3-c1 */
3007 tmp13 = tmp10 + tmp11 + tmp12 -
3008 MULTIPLY(z1, FIX(1.835730603)); /* c9+c11+c13-c15 */
3009 z1 = MULTIPLY(z2 + z3, FIX(0.138617169)); /* c15 */
3010 tmp1 += z1 + MULTIPLY(z2, FIX(0.071888074)); /* c9+c11-c3-c15 */
3011 tmp2 += z1 - MULTIPLY(z3, FIX(1.125726048)); /* c5+c7+c15-c3 */
3012 z1 = MULTIPLY(z3 - z2, FIX(1.407403738)); /* c1 */
3013 tmp11 += z1 - MULTIPLY(z3, FIX(0.766367282)); /* c1+c11-c9-c13 */
3014 tmp12 += z1 + MULTIPLY(z2, FIX(1.971951411)); /* c1+c5+c13-c7 */
3015 z2 += z4;
3016 z1 = MULTIPLY(z2, - FIX(0.666655658)); /* -c11 */
3017 tmp1 += z1;
3018 tmp3 += z1 + MULTIPLY(z4, FIX(1.065388962)); /* c3+c11+c15-c7 */
3019 z2 = MULTIPLY(z2, - FIX(1.247225013)); /* -c5 */
3020 tmp10 += z2 + MULTIPLY(z4, FIX(3.141271809)); /* c1+c5+c9-c13 */
3021 tmp12 += z2;
3022 z2 = MULTIPLY(z3 + z4, - FIX(1.353318001)); /* -c3 */
3023 tmp2 += z2;
3024 tmp3 += z2;
3025 z2 = MULTIPLY(z4 - z3, FIX(0.410524528)); /* c13 */
3026 tmp10 += z2;
3027 tmp11 += z2;
3028
3029 /* Final output stage */
3030
3031 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp0,
3032 CONST_BITS+PASS1_BITS+3)
3033 & RANGE_MASK];
3034 outptr[15] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp0,
3035 CONST_BITS+PASS1_BITS+3)
3036 & RANGE_MASK];
3037 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp1,
3038 CONST_BITS+PASS1_BITS+3)
3039 & RANGE_MASK];
3040 outptr[14] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp1,
3041 CONST_BITS+PASS1_BITS+3)
3042 & RANGE_MASK];
3043 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp2,
3044 CONST_BITS+PASS1_BITS+3)
3045 & RANGE_MASK];
3046 outptr[13] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp2,
3047 CONST_BITS+PASS1_BITS+3)
3048 & RANGE_MASK];
3049 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp3,
3050 CONST_BITS+PASS1_BITS+3)
3051 & RANGE_MASK];
3052 outptr[12] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp3,
3053 CONST_BITS+PASS1_BITS+3)
3054 & RANGE_MASK];
3055 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp10,
3056 CONST_BITS+PASS1_BITS+3)
3057 & RANGE_MASK];
3058 outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp10,
3059 CONST_BITS+PASS1_BITS+3)
3060 & RANGE_MASK];
3061 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp11,
3062 CONST_BITS+PASS1_BITS+3)
3063 & RANGE_MASK];
3064 outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp11,
3065 CONST_BITS+PASS1_BITS+3)
3066 & RANGE_MASK];
3067 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp26 + tmp12,
3068 CONST_BITS+PASS1_BITS+3)
3069 & RANGE_MASK];
3070 outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp26 - tmp12,
3071 CONST_BITS+PASS1_BITS+3)
3072 & RANGE_MASK];
3073 outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp27 + tmp13,
3074 CONST_BITS+PASS1_BITS+3)
3075 & RANGE_MASK];
3076 outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp27 - tmp13,
3077 CONST_BITS+PASS1_BITS+3)
3078 & RANGE_MASK];
3079
3080 wsptr += 8; /* advance pointer to next row */
3081 }
3082 }
3083
3084
3085 /*
3086 * Perform dequantization and inverse DCT on one block of coefficients,
3087 * producing a 14x7 output block.
3088 *
3089 * 7-point IDCT in pass 1 (columns), 14-point in pass 2 (rows).
3090 */
3091
3092 GLOBAL(void)
3093 jpeg_idct_14x7 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
3094 JCOEFPTR coef_block,
3095 JSAMPARRAY output_buf, JDIMENSION output_col)
3096 {
3097 INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15, tmp16;
3098 INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26;
3099 INT32 z1, z2, z3, z4;
3100 JCOEFPTR inptr;
3101 ISLOW_MULT_TYPE * quantptr;
3102 int * wsptr;
3103 JSAMPROW outptr;
3104 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
3105 int ctr;
3106 int workspace[8*7]; /* buffers data between passes */
3107 SHIFT_TEMPS
3108
3109 /* Pass 1: process columns from input, store into work array.
3110 * 7-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/14).
3111 */
3112 inptr = coef_block;
3113 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
3114 wsptr = workspace;
3115 for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
3116 /* Even part */
3117
3118 tmp23 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
3119 tmp23 <<= CONST_BITS;
3120 /* Add fudge factor here for final descale. */
3121 tmp23 += ONE << (CONST_BITS-PASS1_BITS-1);
3122
3123 z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
3124 z2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
3125 z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
3126
3127 tmp20 = MULTIPLY(z2 - z3, FIX(0.881747734)); /* c4 */
3128 tmp22 = MULTIPLY(z1 - z2, FIX(0.314692123)); /* c6 */
3129 tmp21 = tmp20 + tmp22 + tmp23 - MULTIPLY(z2, FIX(1.841218003)); /* c2+c4-c6 */
3130 tmp10 = z1 + z3;
3131 z2 -= tmp10;
3132 tmp10 = MULTIPLY(tmp10, FIX(1.274162392)) + tmp23; /* c2 */
3133 tmp20 += tmp10 - MULTIPLY(z3, FIX(0.077722536)); /* c2-c4-c6 */
3134 tmp22 += tmp10 - MULTIPLY(z1, FIX(2.470602249)); /* c2+c4+c6 */
3135 tmp23 += MULTIPLY(z2, FIX(1.414213562)); /* c0 */
3136
3137 /* Odd part */
3138
3139 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
3140 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
3141 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
3142
3143 tmp11 = MULTIPLY(z1 + z2, FIX(0.935414347)); /* (c3+c1-c5)/2 */
3144 tmp12 = MULTIPLY(z1 - z2, FIX(0.170262339)); /* (c3+c5-c1)/2 */
3145 tmp10 = tmp11 - tmp12;
3146 tmp11 += tmp12;
3147 tmp12 = MULTIPLY(z2 + z3, - FIX(1.378756276)); /* -c1 */
3148 tmp11 += tmp12;
3149 z2 = MULTIPLY(z1 + z3, FIX(0.613604268)); /* c5 */
3150 tmp10 += z2;
3151 tmp12 += z2 + MULTIPLY(z3, FIX(1.870828693)); /* c3+c1-c5 */
3152
3153 /* Final output stage */
3154
3155 wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
3156 wsptr[8*6] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
3157 wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
3158 wsptr[8*5] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
3159 wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
3160 wsptr[8*4] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
3161 wsptr[8*3] = (int) RIGHT_SHIFT(tmp23, CONST_BITS-PASS1_BITS);
3162 }
3163
3164 /* Pass 2: process 7 rows from work array, store into output array.
3165 * 14-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/28).
3166 */
3167 wsptr = workspace;
3168 for (ctr = 0; ctr < 7; ctr++) {
3169 outptr = output_buf[ctr] + output_col;
3170
3171 /* Even part */
3172
3173 /* Add fudge factor here for final descale. */
3174 z1 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
3175 z1 <<= CONST_BITS;
3176 z4 = (INT32) wsptr[4];
3177 z2 = MULTIPLY(z4, FIX(1.274162392)); /* c4 */
3178 z3 = MULTIPLY(z4, FIX(0.314692123)); /* c12 */
3179 z4 = MULTIPLY(z4, FIX(0.881747734)); /* c8 */
3180
3181 tmp10 = z1 + z2;
3182 tmp11 = z1 + z3;
3183 tmp12 = z1 - z4;
3184
3185 tmp23 = z1 - ((z2 + z3 - z4) << 1); /* c0 = (c4+c12-c8)*2 */
3186
3187 z1 = (INT32) wsptr[2];
3188 z2 = (INT32) wsptr[6];
3189
3190 z3 = MULTIPLY(z1 + z2, FIX(1.105676686)); /* c6 */
3191
3192 tmp13 = z3 + MULTIPLY(z1, FIX(0.273079590)); /* c2-c6 */
3193 tmp14 = z3 - MULTIPLY(z2, FIX(1.719280954)); /* c6+c10 */
3194 tmp15 = MULTIPLY(z1, FIX(0.613604268)) - /* c10 */
3195 MULTIPLY(z2, FIX(1.378756276)); /* c2 */
3196
3197 tmp20 = tmp10 + tmp13;
3198 tmp26 = tmp10 - tmp13;
3199 tmp21 = tmp11 + tmp14;
3200 tmp25 = tmp11 - tmp14;
3201 tmp22 = tmp12 + tmp15;
3202 tmp24 = tmp12 - tmp15;
3203
3204 /* Odd part */
3205
3206 z1 = (INT32) wsptr[1];
3207 z2 = (INT32) wsptr[3];
3208 z3 = (INT32) wsptr[5];
3209 z4 = (INT32) wsptr[7];
3210 z4 <<= CONST_BITS;
3211
3212 tmp14 = z1 + z3;
3213 tmp11 = MULTIPLY(z1 + z2, FIX(1.334852607)); /* c3 */
3214 tmp12 = MULTIPLY(tmp14, FIX(1.197448846)); /* c5 */
3215 tmp10 = tmp11 + tmp12 + z4 - MULTIPLY(z1, FIX(1.126980169)); /* c3+c5-c1 */
3216 tmp14 = MULTIPLY(tmp14, FIX(0.752406978)); /* c9 */
3217 tmp16 = tmp14 - MULTIPLY(z1, FIX(1.061150426)); /* c9+c11-c13 */
3218 z1 -= z2;
3219 tmp15 = MULTIPLY(z1, FIX(0.467085129)) - z4; /* c11 */
3220 tmp16 += tmp15;
3221 tmp13 = MULTIPLY(z2 + z3, - FIX(0.158341681)) - z4; /* -c13 */
3222 tmp11 += tmp13 - MULTIPLY(z2, FIX(0.424103948)); /* c3-c9-c13 */
3223 tmp12 += tmp13 - MULTIPLY(z3, FIX(2.373959773)); /* c3+c5-c13 */
3224 tmp13 = MULTIPLY(z3 - z2, FIX(1.405321284)); /* c1 */
3225 tmp14 += tmp13 + z4 - MULTIPLY(z3, FIX(1.6906431334)); /* c1+c9-c11 */
3226 tmp15 += tmp13 + MULTIPLY(z2, FIX(0.674957567)); /* c1+c11-c5 */
3227
3228 tmp13 = ((z1 - z3) << CONST_BITS) + z4;
3229
3230 /* Final output stage */
3231
3232 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
3233 CONST_BITS+PASS1_BITS+3)
3234 & RANGE_MASK];
3235 outptr[13] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
3236 CONST_BITS+PASS1_BITS+3)
3237 & RANGE_MASK];
3238 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
3239 CONST_BITS+PASS1_BITS+3)
3240 & RANGE_MASK];
3241 outptr[12] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
3242 CONST_BITS+PASS1_BITS+3)
3243 & RANGE_MASK];
3244 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
3245 CONST_BITS+PASS1_BITS+3)
3246 & RANGE_MASK];
3247 outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
3248 CONST_BITS+PASS1_BITS+3)
3249 & RANGE_MASK];
3250 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
3251 CONST_BITS+PASS1_BITS+3)
3252 & RANGE_MASK];
3253 outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
3254 CONST_BITS+PASS1_BITS+3)
3255 & RANGE_MASK];
3256 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
3257 CONST_BITS+PASS1_BITS+3)
3258 & RANGE_MASK];
3259 outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
3260 CONST_BITS+PASS1_BITS+3)
3261 & RANGE_MASK];
3262 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp15,
3263 CONST_BITS+PASS1_BITS+3)
3264 & RANGE_MASK];
3265 outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp15,
3266 CONST_BITS+PASS1_BITS+3)
3267 & RANGE_MASK];
3268 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp26 + tmp16,
3269 CONST_BITS+PASS1_BITS+3)
3270 & RANGE_MASK];
3271 outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp26 - tmp16,
3272 CONST_BITS+PASS1_BITS+3)
3273 & RANGE_MASK];
3274
3275 wsptr += 8; /* advance pointer to next row */
3276 }
3277 }
3278
3279
3280 /*
3281 * Perform dequantization and inverse DCT on one block of coefficients,
3282 * producing a 12x6 output block.
3283 *
3284 * 6-point IDCT in pass 1 (columns), 12-point in pass 2 (rows).
3285 */
3286
3287 GLOBAL(void)
3288 jpeg_idct_12x6 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
3289 JCOEFPTR coef_block,
3290 JSAMPARRAY output_buf, JDIMENSION output_col)
3291 {
3292 INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15;
3293 INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25;
3294 INT32 z1, z2, z3, z4;
3295 JCOEFPTR inptr;
3296 ISLOW_MULT_TYPE * quantptr;
3297 int * wsptr;
3298 JSAMPROW outptr;
3299 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
3300 int ctr;
3301 int workspace[8*6]; /* buffers data between passes */
3302 SHIFT_TEMPS
3303
3304 /* Pass 1: process columns from input, store into work array.
3305 * 6-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/12).
3306 */
3307 inptr = coef_block;
3308 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
3309 wsptr = workspace;
3310 for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
3311 /* Even part */
3312
3313 tmp10 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
3314 tmp10 <<= CONST_BITS;
3315 /* Add fudge factor here for final descale. */
3316 tmp10 += ONE << (CONST_BITS-PASS1_BITS-1);
3317 tmp12 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
3318 tmp20 = MULTIPLY(tmp12, FIX(0.707106781)); /* c4 */
3319 tmp11 = tmp10 + tmp20;
3320 tmp21 = RIGHT_SHIFT(tmp10 - tmp20 - tmp20, CONST_BITS-PASS1_BITS);
3321 tmp20 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
3322 tmp10 = MULTIPLY(tmp20, FIX(1.224744871)); /* c2 */
3323 tmp20 = tmp11 + tmp10;
3324 tmp22 = tmp11 - tmp10;
3325
3326 /* Odd part */
3327
3328 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
3329 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
3330 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
3331 tmp11 = MULTIPLY(z1 + z3, FIX(0.366025404)); /* c5 */
3332 tmp10 = tmp11 + ((z1 + z2) << CONST_BITS);
3333 tmp12 = tmp11 + ((z3 - z2) << CONST_BITS);
3334 tmp11 = (z1 - z2 - z3) << PASS1_BITS;
3335
3336 /* Final output stage */
3337
3338 wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
3339 wsptr[8*5] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
3340 wsptr[8*1] = (int) (tmp21 + tmp11);
3341 wsptr[8*4] = (int) (tmp21 - tmp11);
3342 wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
3343 wsptr[8*3] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
3344 }
3345
3346 /* Pass 2: process 6 rows from work array, store into output array.
3347 * 12-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/24).
3348 */
3349 wsptr = workspace;
3350 for (ctr = 0; ctr < 6; ctr++) {
3351 outptr = output_buf[ctr] + output_col;
3352
3353 /* Even part */
3354
3355 /* Add fudge factor here for final descale. */
3356 z3 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
3357 z3 <<= CONST_BITS;
3358
3359 z4 = (INT32) wsptr[4];
3360 z4 = MULTIPLY(z4, FIX(1.224744871)); /* c4 */
3361
3362 tmp10 = z3 + z4;
3363 tmp11 = z3 - z4;
3364
3365 z1 = (INT32) wsptr[2];
3366 z4 = MULTIPLY(z1, FIX(1.366025404)); /* c2 */
3367 z1 <<= CONST_BITS;
3368 z2 = (INT32) wsptr[6];
3369 z2 <<= CONST_BITS;
3370
3371 tmp12 = z1 - z2;
3372
3373 tmp21 = z3 + tmp12;
3374 tmp24 = z3 - tmp12;
3375
3376 tmp12 = z4 + z2;
3377
3378 tmp20 = tmp10 + tmp12;
3379 tmp25 = tmp10 - tmp12;
3380
3381 tmp12 = z4 - z1 - z2;
3382
3383 tmp22 = tmp11 + tmp12;
3384 tmp23 = tmp11 - tmp12;
3385
3386 /* Odd part */
3387
3388 z1 = (INT32) wsptr[1];
3389 z2 = (INT32) wsptr[3];
3390 z3 = (INT32) wsptr[5];
3391 z4 = (INT32) wsptr[7];
3392
3393 tmp11 = MULTIPLY(z2, FIX(1.306562965)); /* c3 */
3394 tmp14 = MULTIPLY(z2, - FIX_0_541196100); /* -c9 */
3395
3396 tmp10 = z1 + z3;
3397 tmp15 = MULTIPLY(tmp10 + z4, FIX(0.860918669)); /* c7 */
3398 tmp12 = tmp15 + MULTIPLY(tmp10, FIX(0.261052384)); /* c5-c7 */
3399 tmp10 = tmp12 + tmp11 + MULTIPLY(z1, FIX(0.280143716)); /* c1-c5 */
3400 tmp13 = MULTIPLY(z3 + z4, - FIX(1.045510580)); /* -(c7+c11) */
3401 tmp12 += tmp13 + tmp14 - MULTIPLY(z3, FIX(1.478575242)); /* c1+c5-c7-c11 */
3402 tmp13 += tmp15 - tmp11 + MULTIPLY(z4, FIX(1.586706681)); /* c1+c11 */
3403 tmp15 += tmp14 - MULTIPLY(z1, FIX(0.676326758)) - /* c7-c11 */
3404 MULTIPLY(z4, FIX(1.982889723)); /* c5+c7 */
3405
3406 z1 -= z4;
3407 z2 -= z3;
3408 z3 = MULTIPLY(z1 + z2, FIX_0_541196100); /* c9 */
3409 tmp11 = z3 + MULTIPLY(z1, FIX_0_765366865); /* c3-c9 */
3410 tmp14 = z3 - MULTIPLY(z2, FIX_1_847759065); /* c3+c9 */
3411
3412 /* Final output stage */
3413
3414 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
3415 CONST_BITS+PASS1_BITS+3)
3416 & RANGE_MASK];
3417 outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
3418 CONST_BITS+PASS1_BITS+3)
3419 & RANGE_MASK];
3420 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
3421 CONST_BITS+PASS1_BITS+3)
3422 & RANGE_MASK];
3423 outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
3424 CONST_BITS+PASS1_BITS+3)
3425 & RANGE_MASK];
3426 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
3427 CONST_BITS+PASS1_BITS+3)
3428 & RANGE_MASK];
3429 outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
3430 CONST_BITS+PASS1_BITS+3)
3431 & RANGE_MASK];
3432 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
3433 CONST_BITS+PASS1_BITS+3)
3434 & RANGE_MASK];
3435 outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
3436 CONST_BITS+PASS1_BITS+3)
3437 & RANGE_MASK];
3438 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
3439 CONST_BITS+PASS1_BITS+3)
3440 & RANGE_MASK];
3441 outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
3442 CONST_BITS+PASS1_BITS+3)
3443 & RANGE_MASK];
3444 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp15,
3445 CONST_BITS+PASS1_BITS+3)
3446 & RANGE_MASK];
3447 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp15,
3448 CONST_BITS+PASS1_BITS+3)
3449 & RANGE_MASK];
3450
3451 wsptr += 8; /* advance pointer to next row */
3452 }
3453 }
3454
3455
3456 /*
3457 * Perform dequantization and inverse DCT on one block of coefficients,
3458 * producing a 10x5 output block.
3459 *
3460 * 5-point IDCT in pass 1 (columns), 10-point in pass 2 (rows).
3461 */
3462
3463 GLOBAL(void)
3464 jpeg_idct_10x5 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
3465 JCOEFPTR coef_block,
3466 JSAMPARRAY output_buf, JDIMENSION output_col)
3467 {
3468 INT32 tmp10, tmp11, tmp12, tmp13, tmp14;
3469 INT32 tmp20, tmp21, tmp22, tmp23, tmp24;
3470 INT32 z1, z2, z3, z4;
3471 JCOEFPTR inptr;
3472 ISLOW_MULT_TYPE * quantptr;
3473 int * wsptr;
3474 JSAMPROW outptr;
3475 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
3476 int ctr;
3477 int workspace[8*5]; /* buffers data between passes */
3478 SHIFT_TEMPS
3479
3480 /* Pass 1: process columns from input, store into work array.
3481 * 5-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/10).
3482 */
3483 inptr = coef_block;
3484 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
3485 wsptr = workspace;
3486 for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
3487 /* Even part */
3488
3489 tmp12 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
3490 tmp12 <<= CONST_BITS;
3491 /* Add fudge factor here for final descale. */
3492 tmp12 += ONE << (CONST_BITS-PASS1_BITS-1);
3493 tmp13 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
3494 tmp14 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
3495 z1 = MULTIPLY(tmp13 + tmp14, FIX(0.790569415)); /* (c2+c4)/2 */
3496 z2 = MULTIPLY(tmp13 - tmp14, FIX(0.353553391)); /* (c2-c4)/2 */
3497 z3 = tmp12 + z2;
3498 tmp10 = z3 + z1;
3499 tmp11 = z3 - z1;
3500 tmp12 -= z2 << 2;
3501
3502 /* Odd part */
3503
3504 z2 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
3505 z3 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
3506
3507 z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c3 */
3508 tmp13 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c1-c3 */
3509 tmp14 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c1+c3 */
3510
3511 /* Final output stage */
3512
3513 wsptr[8*0] = (int) RIGHT_SHIFT(tmp10 + tmp13, CONST_BITS-PASS1_BITS);
3514 wsptr[8*4] = (int) RIGHT_SHIFT(tmp10 - tmp13, CONST_BITS-PASS1_BITS);
3515 wsptr[8*1] = (int) RIGHT_SHIFT(tmp11 + tmp14, CONST_BITS-PASS1_BITS);
3516 wsptr[8*3] = (int) RIGHT_SHIFT(tmp11 - tmp14, CONST_BITS-PASS1_BITS);
3517 wsptr[8*2] = (int) RIGHT_SHIFT(tmp12, CONST_BITS-PASS1_BITS);
3518 }
3519
3520 /* Pass 2: process 5 rows from work array, store into output array.
3521 * 10-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/20).
3522 */
3523 wsptr = workspace;
3524 for (ctr = 0; ctr < 5; ctr++) {
3525 outptr = output_buf[ctr] + output_col;
3526
3527 /* Even part */
3528
3529 /* Add fudge factor here for final descale. */
3530 z3 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
3531 z3 <<= CONST_BITS;
3532 z4 = (INT32) wsptr[4];
3533 z1 = MULTIPLY(z4, FIX(1.144122806)); /* c4 */
3534 z2 = MULTIPLY(z4, FIX(0.437016024)); /* c8 */
3535 tmp10 = z3 + z1;
3536 tmp11 = z3 - z2;
3537
3538 tmp22 = z3 - ((z1 - z2) << 1); /* c0 = (c4-c8)*2 */
3539
3540 z2 = (INT32) wsptr[2];
3541 z3 = (INT32) wsptr[6];
3542
3543 z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c6 */
3544 tmp12 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c2-c6 */
3545 tmp13 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c2+c6 */
3546
3547 tmp20 = tmp10 + tmp12;
3548 tmp24 = tmp10 - tmp12;
3549 tmp21 = tmp11 + tmp13;
3550 tmp23 = tmp11 - tmp13;
3551
3552 /* Odd part */
3553
3554 z1 = (INT32) wsptr[1];
3555 z2 = (INT32) wsptr[3];
3556 z3 = (INT32) wsptr[5];
3557 z3 <<= CONST_BITS;
3558 z4 = (INT32) wsptr[7];
3559
3560 tmp11 = z2 + z4;
3561 tmp13 = z2 - z4;
3562
3563 tmp12 = MULTIPLY(tmp13, FIX(0.309016994)); /* (c3-c7)/2 */
3564
3565 z2 = MULTIPLY(tmp11, FIX(0.951056516)); /* (c3+c7)/2 */
3566 z4 = z3 + tmp12;
3567
3568 tmp10 = MULTIPLY(z1, FIX(1.396802247)) + z2 + z4; /* c1 */
3569 tmp14 = MULTIPLY(z1, FIX(0.221231742)) - z2 + z4; /* c9 */
3570
3571 z2 = MULTIPLY(tmp11, FIX(0.587785252)); /* (c1-c9)/2 */
3572 z4 = z3 - tmp12 - (tmp13 << (CONST_BITS - 1));
3573
3574 tmp12 = ((z1 - tmp13) << CONST_BITS) - z3;
3575
3576 tmp11 = MULTIPLY(z1, FIX(1.260073511)) - z2 - z4; /* c3 */
3577 tmp13 = MULTIPLY(z1, FIX(0.642039522)) - z2 + z4; /* c7 */
3578
3579 /* Final output stage */
3580
3581 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
3582 CONST_BITS+PASS1_BITS+3)
3583 & RANGE_MASK];
3584 outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
3585 CONST_BITS+PASS1_BITS+3)
3586 & RANGE_MASK];
3587 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
3588 CONST_BITS+PASS1_BITS+3)
3589 & RANGE_MASK];
3590 outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
3591 CONST_BITS+PASS1_BITS+3)
3592 & RANGE_MASK];
3593 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
3594 CONST_BITS+PASS1_BITS+3)
3595 & RANGE_MASK];
3596 outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
3597 CONST_BITS+PASS1_BITS+3)
3598 & RANGE_MASK];
3599 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
3600 CONST_BITS+PASS1_BITS+3)
3601 & RANGE_MASK];
3602 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
3603 CONST_BITS+PASS1_BITS+3)
3604 & RANGE_MASK];
3605 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
3606 CONST_BITS+PASS1_BITS+3)
3607 & RANGE_MASK];
3608 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
3609 CONST_BITS+PASS1_BITS+3)
3610 & RANGE_MASK];
3611
3612 wsptr += 8; /* advance pointer to next row */
3613 }
3614 }
3615
3616
3617 /*
3618 * Perform dequantization and inverse DCT on one block of coefficients,
3619 * producing a 8x4 output block.
3620 *
3621 * 4-point IDCT in pass 1 (columns), 8-point in pass 2 (rows).
3622 */
3623
3624 GLOBAL(void)
3625 jpeg_idct_8x4 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
3626 JCOEFPTR coef_block,
3627 JSAMPARRAY output_buf, JDIMENSION output_col)
3628 {
3629 INT32 tmp0, tmp1, tmp2, tmp3;
3630 INT32 tmp10, tmp11, tmp12, tmp13;
3631 INT32 z1, z2, z3;
3632 JCOEFPTR inptr;
3633 ISLOW_MULT_TYPE * quantptr;
3634 int * wsptr;
3635 JSAMPROW outptr;
3636 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
3637 int ctr;
3638 int workspace[8*4]; /* buffers data between passes */
3639 SHIFT_TEMPS
3640
3641 /* Pass 1: process columns from input, store into work array.
3642 * 4-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/16).
3643 */
3644 inptr = coef_block;
3645 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
3646 wsptr = workspace;
3647 for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
3648 /* Even part */
3649
3650 tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
3651 tmp2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
3652
3653 tmp10 = (tmp0 + tmp2) << PASS1_BITS;
3654 tmp12 = (tmp0 - tmp2) << PASS1_BITS;
3655
3656 /* Odd part */
3657 /* Same rotation as in the even part of the 8x8 LL&M IDCT */
3658
3659 z2 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
3660 z3 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
3661
3662 z1 = MULTIPLY(z2 + z3, FIX_0_541196100); /* c6 */
3663 /* Add fudge factor here for final descale. */
3664 z1 += ONE << (CONST_BITS-PASS1_BITS-1);
3665 tmp0 = RIGHT_SHIFT(z1 + MULTIPLY(z2, FIX_0_765366865), /* c2-c6 */
3666 CONST_BITS-PASS1_BITS);
3667 tmp2 = RIGHT_SHIFT(z1 - MULTIPLY(z3, FIX_1_847759065), /* c2+c6 */
3668 CONST_BITS-PASS1_BITS);
3669
3670 /* Final output stage */
3671
3672 wsptr[8*0] = (int) (tmp10 + tmp0);
3673 wsptr[8*3] = (int) (tmp10 - tmp0);
3674 wsptr[8*1] = (int) (tmp12 + tmp2);
3675 wsptr[8*2] = (int) (tmp12 - tmp2);
3676 }
3677
3678 /* Pass 2: process rows from work array, store into output array. */
3679 /* Note that we must descale the results by a factor of 8 == 2**3, */
3680 /* and also undo the PASS1_BITS scaling. */
3681
3682 wsptr = workspace;
3683 for (ctr = 0; ctr < 4; ctr++) {
3684 outptr = output_buf[ctr] + output_col;
3685
3686 /* Even part: reverse the even part of the forward DCT. */
3687 /* The rotator is sqrt(2)*c(-6). */
3688
3689 z2 = (INT32) wsptr[2];
3690 z3 = (INT32) wsptr[6];
3691
3692 z1 = MULTIPLY(z2 + z3, FIX_0_541196100);
3693 tmp2 = z1 + MULTIPLY(z2, FIX_0_765366865);
3694 tmp3 = z1 - MULTIPLY(z3, FIX_1_847759065);
3695
3696 /* Add fudge factor here for final descale. */
3697 z2 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
3698 z3 = (INT32) wsptr[4];
3699
3700 tmp0 = (z2 + z3) << CONST_BITS;
3701 tmp1 = (z2 - z3) << CONST_BITS;
3702
3703 tmp10 = tmp0 + tmp2;
3704 tmp13 = tmp0 - tmp2;
3705 tmp11 = tmp1 + tmp3;
3706 tmp12 = tmp1 - tmp3;
3707
3708 /* Odd part per figure 8; the matrix is unitary and hence its
3709 * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively.
3710 */
3711
3712 tmp0 = (INT32) wsptr[7];
3713 tmp1 = (INT32) wsptr[5];
3714 tmp2 = (INT32) wsptr[3];
3715 tmp3 = (INT32) wsptr[1];
3716
3717 z2 = tmp0 + tmp2;
3718 z3 = tmp1 + tmp3;
3719
3720 z1 = MULTIPLY(z2 + z3, FIX_1_175875602); /* sqrt(2) * c3 */
3721 z2 = MULTIPLY(z2, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
3722 z3 = MULTIPLY(z3, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
3723 z2 += z1;
3724 z3 += z1;
3725
3726 z1 = MULTIPLY(tmp0 + tmp3, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */
3727 tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
3728 tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */
3729 tmp0 += z1 + z2;
3730 tmp3 += z1 + z3;
3731
3732 z1 = MULTIPLY(tmp1 + tmp2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
3733 tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
3734 tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
3735 tmp1 += z1 + z3;
3736 tmp2 += z1 + z2;
3737
3738 /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */
3739
3740 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp3,
3741 CONST_BITS+PASS1_BITS+3)
3742 & RANGE_MASK];
3743 outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp3,
3744 CONST_BITS+PASS1_BITS+3)
3745 & RANGE_MASK];
3746 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp2,
3747 CONST_BITS+PASS1_BITS+3)
3748 & RANGE_MASK];
3749 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp2,
3750 CONST_BITS+PASS1_BITS+3)
3751 & RANGE_MASK];
3752 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp1,
3753 CONST_BITS+PASS1_BITS+3)
3754 & RANGE_MASK];
3755 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp1,
3756 CONST_BITS+PASS1_BITS+3)
3757 & RANGE_MASK];
3758 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp13 + tmp0,
3759 CONST_BITS+PASS1_BITS+3)
3760 & RANGE_MASK];
3761 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp13 - tmp0,
3762 CONST_BITS+PASS1_BITS+3)
3763 & RANGE_MASK];
3764
3765 wsptr += DCTSIZE; /* advance pointer to next row */
3766 }
3767 }
3768
3769
3770 /*
3771 * Perform dequantization and inverse DCT on one block of coefficients,
3772 * producing a reduced-size 6x3 output block.
3773 *
3774 * 3-point IDCT in pass 1 (columns), 6-point in pass 2 (rows).
3775 */
3776
3777 GLOBAL(void)
3778 jpeg_idct_6x3 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
3779 JCOEFPTR coef_block,
3780 JSAMPARRAY output_buf, JDIMENSION output_col)
3781 {
3782 INT32 tmp0, tmp1, tmp2, tmp10, tmp11, tmp12;
3783 INT32 z1, z2, z3;
3784 JCOEFPTR inptr;
3785 ISLOW_MULT_TYPE * quantptr;
3786 int * wsptr;
3787 JSAMPROW outptr;
3788 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
3789 int ctr;
3790 int workspace[6*3]; /* buffers data between passes */
3791 SHIFT_TEMPS
3792
3793 /* Pass 1: process columns from input, store into work array.
3794 * 3-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/6).
3795 */
3796 inptr = coef_block;
3797 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
3798 wsptr = workspace;
3799 for (ctr = 0; ctr < 6; ctr++, inptr++, quantptr++, wsptr++) {
3800 /* Even part */
3801
3802 tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
3803 tmp0 <<= CONST_BITS;
3804 /* Add fudge factor here for final descale. */
3805 tmp0 += ONE << (CONST_BITS-PASS1_BITS-1);
3806 tmp2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
3807 tmp12 = MULTIPLY(tmp2, FIX(0.707106781)); /* c2 */
3808 tmp10 = tmp0 + tmp12;
3809 tmp2 = tmp0 - tmp12 - tmp12;
3810
3811 /* Odd part */
3812
3813 tmp12 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
3814 tmp0 = MULTIPLY(tmp12, FIX(1.224744871)); /* c1 */
3815
3816 /* Final output stage */
3817
3818 wsptr[6*0] = (int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS-PASS1_BITS);
3819 wsptr[6*2] = (int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS-PASS1_BITS);
3820 wsptr[6*1] = (int) RIGHT_SHIFT(tmp2, CONST_BITS-PASS1_BITS);
3821 }
3822
3823 /* Pass 2: process 3 rows from work array, store into output array.
3824 * 6-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/12).
3825 */
3826 wsptr = workspace;
3827 for (ctr = 0; ctr < 3; ctr++) {
3828 outptr = output_buf[ctr] + output_col;
3829
3830 /* Even part */
3831
3832 /* Add fudge factor here for final descale. */
3833 tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
3834 tmp0 <<= CONST_BITS;
3835 tmp2 = (INT32) wsptr[4];
3836 tmp10 = MULTIPLY(tmp2, FIX(0.707106781)); /* c4 */
3837 tmp1 = tmp0 + tmp10;
3838 tmp11 = tmp0 - tmp10 - tmp10;
3839 tmp10 = (INT32) wsptr[2];
3840 tmp0 = MULTIPLY(tmp10, FIX(1.224744871)); /* c2 */
3841 tmp10 = tmp1 + tmp0;
3842 tmp12 = tmp1 - tmp0;
3843
3844 /* Odd part */
3845
3846 z1 = (INT32) wsptr[1];
3847 z2 = (INT32) wsptr[3];
3848 z3 = (INT32) wsptr[5];
3849 tmp1 = MULTIPLY(z1 + z3, FIX(0.366025404)); /* c5 */
3850 tmp0 = tmp1 + ((z1 + z2) << CONST_BITS);
3851 tmp2 = tmp1 + ((z3 - z2) << CONST_BITS);
3852 tmp1 = (z1 - z2 - z3) << CONST_BITS;
3853
3854 /* Final output stage */
3855
3856 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
3857 CONST_BITS+PASS1_BITS+3)
3858 & RANGE_MASK];
3859 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
3860 CONST_BITS+PASS1_BITS+3)
3861 & RANGE_MASK];
3862 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp1,
3863 CONST_BITS+PASS1_BITS+3)
3864 & RANGE_MASK];
3865 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp1,
3866 CONST_BITS+PASS1_BITS+3)
3867 & RANGE_MASK];
3868 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp2,
3869 CONST_BITS+PASS1_BITS+3)
3870 & RANGE_MASK];
3871 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp2,
3872 CONST_BITS+PASS1_BITS+3)
3873 & RANGE_MASK];
3874
3875 wsptr += 6; /* advance pointer to next row */
3876 }
3877 }
3878
3879
3880 /*
3881 * Perform dequantization and inverse DCT on one block of coefficients,
3882 * producing a 4x2 output block.
3883 *
3884 * 2-point IDCT in pass 1 (columns), 4-point in pass 2 (rows).
3885 */
3886
3887 GLOBAL(void)
3888 jpeg_idct_4x2 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
3889 JCOEFPTR coef_block,
3890 JSAMPARRAY output_buf, JDIMENSION output_col)
3891 {
3892 INT32 tmp0, tmp2, tmp10, tmp12;
3893 INT32 z1, z2, z3;
3894 JCOEFPTR inptr;
3895 ISLOW_MULT_TYPE * quantptr;
3896 INT32 * wsptr;
3897 JSAMPROW outptr;
3898 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
3899 int ctr;
3900 INT32 workspace[4*2]; /* buffers data between passes */
3901 SHIFT_TEMPS
3902
3903 /* Pass 1: process columns from input, store into work array. */
3904
3905 inptr = coef_block;
3906 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
3907 wsptr = workspace;
3908 for (ctr = 0; ctr < 4; ctr++, inptr++, quantptr++, wsptr++) {
3909 /* Even part */
3910
3911 tmp10 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
3912
3913 /* Odd part */
3914
3915 tmp0 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
3916
3917 /* Final output stage */
3918
3919 wsptr[4*0] = tmp10 + tmp0;
3920 wsptr[4*1] = tmp10 - tmp0;
3921 }
3922
3923 /* Pass 2: process 2 rows from work array, store into output array.
3924 * 4-point IDCT kernel,
3925 * cK represents sqrt(2) * cos(K*pi/16) [refers to 8-point IDCT].
3926 */
3927 wsptr = workspace;
3928 for (ctr = 0; ctr < 2; ctr++) {
3929 outptr = output_buf[ctr] + output_col;
3930
3931 /* Even part */
3932
3933 /* Add fudge factor here for final descale. */
3934 tmp0 = wsptr[0] + (ONE << 2);
3935 tmp2 = wsptr[2];
3936
3937 tmp10 = (tmp0 + tmp2) << CONST_BITS;
3938 tmp12 = (tmp0 - tmp2) << CONST_BITS;
3939
3940 /* Odd part */
3941 /* Same rotation as in the even part of the 8x8 LL&M IDCT */
3942
3943 z2 = wsptr[1];
3944 z3 = wsptr[3];
3945
3946 z1 = MULTIPLY(z2 + z3, FIX_0_541196100); /* c6 */
3947 tmp0 = z1 + MULTIPLY(z2, FIX_0_765366865); /* c2-c6 */
3948 tmp2 = z1 - MULTIPLY(z3, FIX_1_847759065); /* c2+c6 */
3949
3950 /* Final output stage */
3951
3952 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
3953 CONST_BITS+3)
3954 & RANGE_MASK];
3955 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
3956 CONST_BITS+3)
3957 & RANGE_MASK];
3958 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp2,
3959 CONST_BITS+3)
3960 & RANGE_MASK];
3961 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp2,
3962 CONST_BITS+3)
3963 & RANGE_MASK];
3964
3965 wsptr += 4; /* advance pointer to next row */
3966 }
3967 }
3968
3969
3970 /*
3971 * Perform dequantization and inverse DCT on one block of coefficients,
3972 * producing a 2x1 output block.
3973 *
3974 * 1-point IDCT in pass 1 (columns), 2-point in pass 2 (rows).
3975 */
3976
3977 GLOBAL(void)
3978 jpeg_idct_2x1 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
3979 JCOEFPTR coef_block,
3980 JSAMPARRAY output_buf, JDIMENSION output_col)
3981 {
3982 INT32 tmp0, tmp10;
3983 ISLOW_MULT_TYPE * quantptr;
3984 JSAMPROW outptr;
3985 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
3986 SHIFT_TEMPS
3987
3988 /* Pass 1: empty. */
3989
3990 /* Pass 2: process 1 row from input, store into output array. */
3991
3992 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
3993 outptr = output_buf[0] + output_col;
3994
3995 /* Even part */
3996
3997 tmp10 = DEQUANTIZE(coef_block[0], quantptr[0]);
3998 /* Add fudge factor here for final descale. */
3999 tmp10 += ONE << 2;
4000
4001 /* Odd part */
4002
4003 tmp0 = DEQUANTIZE(coef_block[1], quantptr[1]);
4004
4005 /* Final output stage */
4006
4007 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0, 3) & RANGE_MASK];
4008 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0, 3) & RANGE_MASK];
4009 }
4010
4011
4012 /*
4013 * Perform dequantization and inverse DCT on one block of coefficients,
4014 * producing a 8x16 output block.
4015 *
4016 * 16-point IDCT in pass 1 (columns), 8-point in pass 2 (rows).
4017 */
4018
4019 GLOBAL(void)
4020 jpeg_idct_8x16 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
4021 JCOEFPTR coef_block,
4022 JSAMPARRAY output_buf, JDIMENSION output_col)
4023 {
4024 INT32 tmp0, tmp1, tmp2, tmp3, tmp10, tmp11, tmp12, tmp13;
4025 INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26, tmp27;
4026 INT32 z1, z2, z3, z4;
4027 JCOEFPTR inptr;
4028 ISLOW_MULT_TYPE * quantptr;
4029 int * wsptr;
4030 JSAMPROW outptr;
4031 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
4032 int ctr;
4033 int workspace[8*16]; /* buffers data between passes */
4034 SHIFT_TEMPS
4035
4036 /* Pass 1: process columns from input, store into work array.
4037 * 16-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/32).
4038 */
4039 inptr = coef_block;
4040 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
4041 wsptr = workspace;
4042 for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
4043 /* Even part */
4044
4045 tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
4046 tmp0 <<= CONST_BITS;
4047 /* Add fudge factor here for final descale. */
4048 tmp0 += ONE << (CONST_BITS-PASS1_BITS-1);
4049
4050 z1 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
4051 tmp1 = MULTIPLY(z1, FIX(1.306562965)); /* c4[16] = c2[8] */
4052 tmp2 = MULTIPLY(z1, FIX_0_541196100); /* c12[16] = c6[8] */
4053
4054 tmp10 = tmp0 + tmp1;
4055 tmp11 = tmp0 - tmp1;
4056 tmp12 = tmp0 + tmp2;
4057 tmp13 = tmp0 - tmp2;
4058
4059 z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
4060 z2 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
4061 z3 = z1 - z2;
4062 z4 = MULTIPLY(z3, FIX(0.275899379)); /* c14[16] = c7[8] */
4063 z3 = MULTIPLY(z3, FIX(1.387039845)); /* c2[16] = c1[8] */
4064
4065 tmp0 = z3 + MULTIPLY(z2, FIX_2_562915447); /* (c6+c2)[16] = (c3+c1)[8] */
4066 tmp1 = z4 + MULTIPLY(z1, FIX_0_899976223); /* (c6-c14)[16] = (c3-c7)[8] */
4067 tmp2 = z3 - MULTIPLY(z1, FIX(0.601344887)); /* (c2-c10)[16] = (c1-c5)[8] */
4068 tmp3 = z4 - MULTIPLY(z2, FIX(0.509795579)); /* (c10-c14)[16] = (c5-c7)[8] */
4069
4070 tmp20 = tmp10 + tmp0;
4071 tmp27 = tmp10 - tmp0;
4072 tmp21 = tmp12 + tmp1;
4073 tmp26 = tmp12 - tmp1;
4074 tmp22 = tmp13 + tmp2;
4075 tmp25 = tmp13 - tmp2;
4076 tmp23 = tmp11 + tmp3;
4077 tmp24 = tmp11 - tmp3;
4078
4079 /* Odd part */
4080
4081 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
4082 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
4083 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
4084 z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
4085
4086 tmp11 = z1 + z3;
4087
4088 tmp1 = MULTIPLY(z1 + z2, FIX(1.353318001)); /* c3 */
4089 tmp2 = MULTIPLY(tmp11, FIX(1.247225013)); /* c5 */
4090 tmp3 = MULTIPLY(z1 + z4, FIX(1.093201867)); /* c7 */
4091 tmp10 = MULTIPLY(z1 - z4, FIX(0.897167586)); /* c9 */
4092 tmp11 = MULTIPLY(tmp11, FIX(0.666655658)); /* c11 */
4093 tmp12 = MULTIPLY(z1 - z2, FIX(0.410524528)); /* c13 */
4094 tmp0 = tmp1 + tmp2 + tmp3 -
4095 MULTIPLY(z1, FIX(2.286341144)); /* c7+c5+c3-c1 */
4096 tmp13 = tmp10 + tmp11 + tmp12 -
4097 MULTIPLY(z1, FIX(1.835730603)); /* c9+c11+c13-c15 */
4098 z1 = MULTIPLY(z2 + z3, FIX(0.138617169)); /* c15 */
4099 tmp1 += z1 + MULTIPLY(z2, FIX(0.071888074)); /* c9+c11-c3-c15 */
4100 tmp2 += z1 - MULTIPLY(z3, FIX(1.125726048)); /* c5+c7+c15-c3 */
4101 z1 = MULTIPLY(z3 - z2, FIX(1.407403738)); /* c1 */
4102 tmp11 += z1 - MULTIPLY(z3, FIX(0.766367282)); /* c1+c11-c9-c13 */
4103 tmp12 += z1 + MULTIPLY(z2, FIX(1.971951411)); /* c1+c5+c13-c7 */
4104 z2 += z4;
4105 z1 = MULTIPLY(z2, - FIX(0.666655658)); /* -c11 */
4106 tmp1 += z1;
4107 tmp3 += z1 + MULTIPLY(z4, FIX(1.065388962)); /* c3+c11+c15-c7 */
4108 z2 = MULTIPLY(z2, - FIX(1.247225013)); /* -c5 */
4109 tmp10 += z2 + MULTIPLY(z4, FIX(3.141271809)); /* c1+c5+c9-c13 */
4110 tmp12 += z2;
4111 z2 = MULTIPLY(z3 + z4, - FIX(1.353318001)); /* -c3 */
4112 tmp2 += z2;
4113 tmp3 += z2;
4114 z2 = MULTIPLY(z4 - z3, FIX(0.410524528)); /* c13 */
4115 tmp10 += z2;
4116 tmp11 += z2;
4117
4118 /* Final output stage */
4119
4120 wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp0, CONST_BITS-PASS1_BITS);
4121 wsptr[8*15] = (int) RIGHT_SHIFT(tmp20 - tmp0, CONST_BITS-PASS1_BITS);
4122 wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp1, CONST_BITS-PASS1_BITS);
4123 wsptr[8*14] = (int) RIGHT_SHIFT(tmp21 - tmp1, CONST_BITS-PASS1_BITS);
4124 wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp2, CONST_BITS-PASS1_BITS);
4125 wsptr[8*13] = (int) RIGHT_SHIFT(tmp22 - tmp2, CONST_BITS-PASS1_BITS);
4126 wsptr[8*3] = (int) RIGHT_SHIFT(tmp23 + tmp3, CONST_BITS-PASS1_BITS);
4127 wsptr[8*12] = (int) RIGHT_SHIFT(tmp23 - tmp3, CONST_BITS-PASS1_BITS);
4128 wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp10, CONST_BITS-PASS1_BITS);
4129 wsptr[8*11] = (int) RIGHT_SHIFT(tmp24 - tmp10, CONST_BITS-PASS1_BITS);
4130 wsptr[8*5] = (int) RIGHT_SHIFT(tmp25 + tmp11, CONST_BITS-PASS1_BITS);
4131 wsptr[8*10] = (int) RIGHT_SHIFT(tmp25 - tmp11, CONST_BITS-PASS1_BITS);
4132 wsptr[8*6] = (int) RIGHT_SHIFT(tmp26 + tmp12, CONST_BITS-PASS1_BITS);
4133 wsptr[8*9] = (int) RIGHT_SHIFT(tmp26 - tmp12, CONST_BITS-PASS1_BITS);
4134 wsptr[8*7] = (int) RIGHT_SHIFT(tmp27 + tmp13, CONST_BITS-PASS1_BITS);
4135 wsptr[8*8] = (int) RIGHT_SHIFT(tmp27 - tmp13, CONST_BITS-PASS1_BITS);
4136 }
4137
4138 /* Pass 2: process rows from work array, store into output array. */
4139 /* Note that we must descale the results by a factor of 8 == 2**3, */
4140 /* and also undo the PASS1_BITS scaling. */
4141
4142 wsptr = workspace;
4143 for (ctr = 0; ctr < 16; ctr++) {
4144 outptr = output_buf[ctr] + output_col;
4145
4146 /* Even part: reverse the even part of the forward DCT. */
4147 /* The rotator is sqrt(2)*c(-6). */
4148
4149 z2 = (INT32) wsptr[2];
4150 z3 = (INT32) wsptr[6];
4151
4152 z1 = MULTIPLY(z2 + z3, FIX_0_541196100);
4153 tmp2 = z1 + MULTIPLY(z2, FIX_0_765366865);
4154 tmp3 = z1 - MULTIPLY(z3, FIX_1_847759065);
4155
4156 /* Add fudge factor here for final descale. */
4157 z2 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
4158 z3 = (INT32) wsptr[4];
4159
4160 tmp0 = (z2 + z3) << CONST_BITS;
4161 tmp1 = (z2 - z3) << CONST_BITS;
4162
4163 tmp10 = tmp0 + tmp2;
4164 tmp13 = tmp0 - tmp2;
4165 tmp11 = tmp1 + tmp3;
4166 tmp12 = tmp1 - tmp3;
4167
4168 /* Odd part per figure 8; the matrix is unitary and hence its
4169 * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively.
4170 */
4171
4172 tmp0 = (INT32) wsptr[7];
4173 tmp1 = (INT32) wsptr[5];
4174 tmp2 = (INT32) wsptr[3];
4175 tmp3 = (INT32) wsptr[1];
4176
4177 z2 = tmp0 + tmp2;
4178 z3 = tmp1 + tmp3;
4179
4180 z1 = MULTIPLY(z2 + z3, FIX_1_175875602); /* sqrt(2) * c3 */
4181 z2 = MULTIPLY(z2, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
4182 z3 = MULTIPLY(z3, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
4183 z2 += z1;
4184 z3 += z1;
4185
4186 z1 = MULTIPLY(tmp0 + tmp3, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */
4187 tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
4188 tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */
4189 tmp0 += z1 + z2;
4190 tmp3 += z1 + z3;
4191
4192 z1 = MULTIPLY(tmp1 + tmp2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
4193 tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
4194 tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
4195 tmp1 += z1 + z3;
4196 tmp2 += z1 + z2;
4197
4198 /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */
4199
4200 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp3,
4201 CONST_BITS+PASS1_BITS+3)
4202 & RANGE_MASK];
4203 outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp3,
4204 CONST_BITS+PASS1_BITS+3)
4205 & RANGE_MASK];
4206 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp2,
4207 CONST_BITS+PASS1_BITS+3)
4208 & RANGE_MASK];
4209 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp2,
4210 CONST_BITS+PASS1_BITS+3)
4211 & RANGE_MASK];
4212 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp1,
4213 CONST_BITS+PASS1_BITS+3)
4214 & RANGE_MASK];
4215 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp1,
4216 CONST_BITS+PASS1_BITS+3)
4217 & RANGE_MASK];
4218 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp13 + tmp0,
4219 CONST_BITS+PASS1_BITS+3)
4220 & RANGE_MASK];
4221 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp13 - tmp0,
4222 CONST_BITS+PASS1_BITS+3)
4223 & RANGE_MASK];
4224
4225 wsptr += DCTSIZE; /* advance pointer to next row */
4226 }
4227 }
4228
4229
4230 /*
4231 * Perform dequantization and inverse DCT on one block of coefficients,
4232 * producing a 7x14 output block.
4233 *
4234 * 14-point IDCT in pass 1 (columns), 7-point in pass 2 (rows).
4235 */
4236
4237 GLOBAL(void)
4238 jpeg_idct_7x14 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
4239 JCOEFPTR coef_block,
4240 JSAMPARRAY output_buf, JDIMENSION output_col)
4241 {
4242 INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15, tmp16;
4243 INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26;
4244 INT32 z1, z2, z3, z4;
4245 JCOEFPTR inptr;
4246 ISLOW_MULT_TYPE * quantptr;
4247 int * wsptr;
4248 JSAMPROW outptr;
4249 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
4250 int ctr;
4251 int workspace[7*14]; /* buffers data between passes */
4252 SHIFT_TEMPS
4253
4254 /* Pass 1: process columns from input, store into work array.
4255 * 14-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/28).
4256 */
4257 inptr = coef_block;
4258 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
4259 wsptr = workspace;
4260 for (ctr = 0; ctr < 7; ctr++, inptr++, quantptr++, wsptr++) {
4261 /* Even part */
4262
4263 z1 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
4264 z1 <<= CONST_BITS;
4265 /* Add fudge factor here for final descale. */
4266 z1 += ONE << (CONST_BITS-PASS1_BITS-1);
4267 z4 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
4268 z2 = MULTIPLY(z4, FIX(1.274162392)); /* c4 */
4269 z3 = MULTIPLY(z4, FIX(0.314692123)); /* c12 */
4270 z4 = MULTIPLY(z4, FIX(0.881747734)); /* c8 */
4271
4272 tmp10 = z1 + z2;
4273 tmp11 = z1 + z3;
4274 tmp12 = z1 - z4;
4275
4276 tmp23 = RIGHT_SHIFT(z1 - ((z2 + z3 - z4) << 1), /* c0 = (c4+c12-c8)*2 */
4277 CONST_BITS-PASS1_BITS);
4278
4279 z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
4280 z2 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
4281
4282 z3 = MULTIPLY(z1 + z2, FIX(1.105676686)); /* c6 */
4283
4284 tmp13 = z3 + MULTIPLY(z1, FIX(0.273079590)); /* c2-c6 */
4285 tmp14 = z3 - MULTIPLY(z2, FIX(1.719280954)); /* c6+c10 */
4286 tmp15 = MULTIPLY(z1, FIX(0.613604268)) - /* c10 */
4287 MULTIPLY(z2, FIX(1.378756276)); /* c2 */
4288
4289 tmp20 = tmp10 + tmp13;
4290 tmp26 = tmp10 - tmp13;
4291 tmp21 = tmp11 + tmp14;
4292 tmp25 = tmp11 - tmp14;
4293 tmp22 = tmp12 + tmp15;
4294 tmp24 = tmp12 - tmp15;
4295
4296 /* Odd part */
4297
4298 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
4299 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
4300 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
4301 z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
4302 tmp13 = z4 << CONST_BITS;
4303
4304 tmp14 = z1 + z3;
4305 tmp11 = MULTIPLY(z1 + z2, FIX(1.334852607)); /* c3 */
4306 tmp12 = MULTIPLY(tmp14, FIX(1.197448846)); /* c5 */
4307 tmp10 = tmp11 + tmp12 + tmp13 - MULTIPLY(z1, FIX(1.126980169)); /* c3+c5-c1 */
4308 tmp14 = MULTIPLY(tmp14, FIX(0.752406978)); /* c9 */
4309 tmp16 = tmp14 - MULTIPLY(z1, FIX(1.061150426)); /* c9+c11-c13 */
4310 z1 -= z2;
4311 tmp15 = MULTIPLY(z1, FIX(0.467085129)) - tmp13; /* c11 */
4312 tmp16 += tmp15;
4313 z1 += z4;
4314 z4 = MULTIPLY(z2 + z3, - FIX(0.158341681)) - tmp13; /* -c13 */
4315 tmp11 += z4 - MULTIPLY(z2, FIX(0.424103948)); /* c3-c9-c13 */
4316 tmp12 += z4 - MULTIPLY(z3, FIX(2.373959773)); /* c3+c5-c13 */
4317 z4 = MULTIPLY(z3 - z2, FIX(1.405321284)); /* c1 */
4318 tmp14 += z4 + tmp13 - MULTIPLY(z3, FIX(1.6906431334)); /* c1+c9-c11 */
4319 tmp15 += z4 + MULTIPLY(z2, FIX(0.674957567)); /* c1+c11-c5 */
4320
4321 tmp13 = (z1 - z3) << PASS1_BITS;
4322
4323 /* Final output stage */
4324
4325 wsptr[7*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
4326 wsptr[7*13] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
4327 wsptr[7*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
4328 wsptr[7*12] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
4329 wsptr[7*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
4330 wsptr[7*11] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
4331 wsptr[7*3] = (int) (tmp23 + tmp13);
4332 wsptr[7*10] = (int) (tmp23 - tmp13);
4333 wsptr[7*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
4334 wsptr[7*9] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
4335 wsptr[7*5] = (int) RIGHT_SHIFT(tmp25 + tmp15, CONST_BITS-PASS1_BITS);
4336 wsptr[7*8] = (int) RIGHT_SHIFT(tmp25 - tmp15, CONST_BITS-PASS1_BITS);
4337 wsptr[7*6] = (int) RIGHT_SHIFT(tmp26 + tmp16, CONST_BITS-PASS1_BITS);
4338 wsptr[7*7] = (int) RIGHT_SHIFT(tmp26 - tmp16, CONST_BITS-PASS1_BITS);
4339 }
4340
4341 /* Pass 2: process 14 rows from work array, store into output array.
4342 * 7-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/14).
4343 */
4344 wsptr = workspace;
4345 for (ctr = 0; ctr < 14; ctr++) {
4346 outptr = output_buf[ctr] + output_col;
4347
4348 /* Even part */
4349
4350 /* Add fudge factor here for final descale. */
4351 tmp23 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
4352 tmp23 <<= CONST_BITS;
4353
4354 z1 = (INT32) wsptr[2];
4355 z2 = (INT32) wsptr[4];
4356 z3 = (INT32) wsptr[6];
4357
4358 tmp20 = MULTIPLY(z2 - z3, FIX(0.881747734)); /* c4 */
4359 tmp22 = MULTIPLY(z1 - z2, FIX(0.314692123)); /* c6 */
4360 tmp21 = tmp20 + tmp22 + tmp23 - MULTIPLY(z2, FIX(1.841218003)); /* c2+c4-c6 */
4361 tmp10 = z1 + z3;
4362 z2 -= tmp10;
4363 tmp10 = MULTIPLY(tmp10, FIX(1.274162392)) + tmp23; /* c2 */
4364 tmp20 += tmp10 - MULTIPLY(z3, FIX(0.077722536)); /* c2-c4-c6 */
4365 tmp22 += tmp10 - MULTIPLY(z1, FIX(2.470602249)); /* c2+c4+c6 */
4366 tmp23 += MULTIPLY(z2, FIX(1.414213562)); /* c0 */
4367
4368 /* Odd part */
4369
4370 z1 = (INT32) wsptr[1];
4371 z2 = (INT32) wsptr[3];
4372 z3 = (INT32) wsptr[5];
4373
4374 tmp11 = MULTIPLY(z1 + z2, FIX(0.935414347)); /* (c3+c1-c5)/2 */
4375 tmp12 = MULTIPLY(z1 - z2, FIX(0.170262339)); /* (c3+c5-c1)/2 */
4376 tmp10 = tmp11 - tmp12;
4377 tmp11 += tmp12;
4378 tmp12 = MULTIPLY(z2 + z3, - FIX(1.378756276)); /* -c1 */
4379 tmp11 += tmp12;
4380 z2 = MULTIPLY(z1 + z3, FIX(0.613604268)); /* c5 */
4381 tmp10 += z2;
4382 tmp12 += z2 + MULTIPLY(z3, FIX(1.870828693)); /* c3+c1-c5 */
4383
4384 /* Final output stage */
4385
4386 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
4387 CONST_BITS+PASS1_BITS+3)
4388 & RANGE_MASK];
4389 outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
4390 CONST_BITS+PASS1_BITS+3)
4391 & RANGE_MASK];
4392 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
4393 CONST_BITS+PASS1_BITS+3)
4394 & RANGE_MASK];
4395 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
4396 CONST_BITS+PASS1_BITS+3)
4397 & RANGE_MASK];
4398 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
4399 CONST_BITS+PASS1_BITS+3)
4400 & RANGE_MASK];
4401 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
4402 CONST_BITS+PASS1_BITS+3)
4403 & RANGE_MASK];
4404 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23,
4405 CONST_BITS+PASS1_BITS+3)
4406 & RANGE_MASK];
4407
4408 wsptr += 7; /* advance pointer to next row */
4409 }
4410 }
4411
4412
4413 /*
4414 * Perform dequantization and inverse DCT on one block of coefficients,
4415 * producing a 6x12 output block.
4416 *
4417 * 12-point IDCT in pass 1 (columns), 6-point in pass 2 (rows).
4418 */
4419
4420 GLOBAL(void)
4421 jpeg_idct_6x12 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
4422 JCOEFPTR coef_block,
4423 JSAMPARRAY output_buf, JDIMENSION output_col)
4424 {
4425 INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15;
4426 INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25;
4427 INT32 z1, z2, z3, z4;
4428 JCOEFPTR inptr;
4429 ISLOW_MULT_TYPE * quantptr;
4430 int * wsptr;
4431 JSAMPROW outptr;
4432 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
4433 int ctr;
4434 int workspace[6*12]; /* buffers data between passes */
4435 SHIFT_TEMPS
4436
4437 /* Pass 1: process columns from input, store into work array.
4438 * 12-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/24).
4439 */
4440 inptr = coef_block;
4441 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
4442 wsptr = workspace;
4443 for (ctr = 0; ctr < 6; ctr++, inptr++, quantptr++, wsptr++) {
4444 /* Even part */
4445
4446 z3 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
4447 z3 <<= CONST_BITS;
4448 /* Add fudge factor here for final descale. */
4449 z3 += ONE << (CONST_BITS-PASS1_BITS-1);
4450
4451 z4 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
4452 z4 = MULTIPLY(z4, FIX(1.224744871)); /* c4 */
4453
4454 tmp10 = z3 + z4;
4455 tmp11 = z3 - z4;
4456
4457 z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
4458 z4 = MULTIPLY(z1, FIX(1.366025404)); /* c2 */
4459 z1 <<= CONST_BITS;
4460 z2 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
4461 z2 <<= CONST_BITS;
4462
4463 tmp12 = z1 - z2;
4464
4465 tmp21 = z3 + tmp12;
4466 tmp24 = z3 - tmp12;
4467
4468 tmp12 = z4 + z2;
4469
4470 tmp20 = tmp10 + tmp12;
4471 tmp25 = tmp10 - tmp12;
4472
4473 tmp12 = z4 - z1 - z2;
4474
4475 tmp22 = tmp11 + tmp12;
4476 tmp23 = tmp11 - tmp12;
4477
4478 /* Odd part */
4479
4480 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
4481 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
4482 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
4483 z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
4484
4485 tmp11 = MULTIPLY(z2, FIX(1.306562965)); /* c3 */
4486 tmp14 = MULTIPLY(z2, - FIX_0_541196100); /* -c9 */
4487
4488 tmp10 = z1 + z3;
4489 tmp15 = MULTIPLY(tmp10 + z4, FIX(0.860918669)); /* c7 */
4490 tmp12 = tmp15 + MULTIPLY(tmp10, FIX(0.261052384)); /* c5-c7 */
4491 tmp10 = tmp12 + tmp11 + MULTIPLY(z1, FIX(0.280143716)); /* c1-c5 */
4492 tmp13 = MULTIPLY(z3 + z4, - FIX(1.045510580)); /* -(c7+c11) */
4493 tmp12 += tmp13 + tmp14 - MULTIPLY(z3, FIX(1.478575242)); /* c1+c5-c7-c11 */
4494 tmp13 += tmp15 - tmp11 + MULTIPLY(z4, FIX(1.586706681)); /* c1+c11 */
4495 tmp15 += tmp14 - MULTIPLY(z1, FIX(0.676326758)) - /* c7-c11 */
4496 MULTIPLY(z4, FIX(1.982889723)); /* c5+c7 */
4497
4498 z1 -= z4;
4499 z2 -= z3;
4500 z3 = MULTIPLY(z1 + z2, FIX_0_541196100); /* c9 */
4501 tmp11 = z3 + MULTIPLY(z1, FIX_0_765366865); /* c3-c9 */
4502 tmp14 = z3 - MULTIPLY(z2, FIX_1_847759065); /* c3+c9 */
4503
4504 /* Final output stage */
4505
4506 wsptr[6*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
4507 wsptr[6*11] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
4508 wsptr[6*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
4509 wsptr[6*10] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
4510 wsptr[6*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
4511 wsptr[6*9] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
4512 wsptr[6*3] = (int) RIGHT_SHIFT(tmp23 + tmp13, CONST_BITS-PASS1_BITS);
4513 wsptr[6*8] = (int) RIGHT_SHIFT(tmp23 - tmp13, CONST_BITS-PASS1_BITS);
4514 wsptr[6*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
4515 wsptr[6*7] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
4516 wsptr[6*5] = (int) RIGHT_SHIFT(tmp25 + tmp15, CONST_BITS-PASS1_BITS);
4517 wsptr[6*6] = (int) RIGHT_SHIFT(tmp25 - tmp15, CONST_BITS-PASS1_BITS);
4518 }
4519
4520 /* Pass 2: process 12 rows from work array, store into output array.
4521 * 6-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/12).
4522 */
4523 wsptr = workspace;
4524 for (ctr = 0; ctr < 12; ctr++) {
4525 outptr = output_buf[ctr] + output_col;
4526
4527 /* Even part */
4528
4529 /* Add fudge factor here for final descale. */
4530 tmp10 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
4531 tmp10 <<= CONST_BITS;
4532 tmp12 = (INT32) wsptr[4];
4533 tmp20 = MULTIPLY(tmp12, FIX(0.707106781)); /* c4 */
4534 tmp11 = tmp10 + tmp20;
4535 tmp21 = tmp10 - tmp20 - tmp20;
4536 tmp20 = (INT32) wsptr[2];
4537 tmp10 = MULTIPLY(tmp20, FIX(1.224744871)); /* c2 */
4538 tmp20 = tmp11 + tmp10;
4539 tmp22 = tmp11 - tmp10;
4540
4541 /* Odd part */
4542
4543 z1 = (INT32) wsptr[1];
4544 z2 = (INT32) wsptr[3];
4545 z3 = (INT32) wsptr[5];
4546 tmp11 = MULTIPLY(z1 + z3, FIX(0.366025404)); /* c5 */
4547 tmp10 = tmp11 + ((z1 + z2) << CONST_BITS);
4548 tmp12 = tmp11 + ((z3 - z2) << CONST_BITS);
4549 tmp11 = (z1 - z2 - z3) << CONST_BITS;
4550
4551 /* Final output stage */
4552
4553 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
4554 CONST_BITS+PASS1_BITS+3)
4555 & RANGE_MASK];
4556 outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
4557 CONST_BITS+PASS1_BITS+3)
4558 & RANGE_MASK];
4559 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
4560 CONST_BITS+PASS1_BITS+3)
4561 & RANGE_MASK];
4562 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
4563 CONST_BITS+PASS1_BITS+3)
4564 & RANGE_MASK];
4565 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
4566 CONST_BITS+PASS1_BITS+3)
4567 & RANGE_MASK];
4568 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
4569 CONST_BITS+PASS1_BITS+3)
4570 & RANGE_MASK];
4571
4572 wsptr += 6; /* advance pointer to next row */
4573 }
4574 }
4575
4576
4577 /*
4578 * Perform dequantization and inverse DCT on one block of coefficients,
4579 * producing a 5x10 output block.
4580 *
4581 * 10-point IDCT in pass 1 (columns), 5-point in pass 2 (rows).
4582 */
4583
4584 GLOBAL(void)
4585 jpeg_idct_5x10 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
4586 JCOEFPTR coef_block,
4587 JSAMPARRAY output_buf, JDIMENSION output_col)
4588 {
4589 INT32 tmp10, tmp11, tmp12, tmp13, tmp14;
4590 INT32 tmp20, tmp21, tmp22, tmp23, tmp24;
4591 INT32 z1, z2, z3, z4, z5;
4592 JCOEFPTR inptr;
4593 ISLOW_MULT_TYPE * quantptr;
4594 int * wsptr;
4595 JSAMPROW outptr;
4596 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
4597 int ctr;
4598 int workspace[5*10]; /* buffers data between passes */
4599 SHIFT_TEMPS
4600
4601 /* Pass 1: process columns from input, store into work array.
4602 * 10-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/20).
4603 */
4604 inptr = coef_block;
4605 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
4606 wsptr = workspace;
4607 for (ctr = 0; ctr < 5; ctr++, inptr++, quantptr++, wsptr++) {
4608 /* Even part */
4609
4610 z3 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
4611 z3 <<= CONST_BITS;
4612 /* Add fudge factor here for final descale. */
4613 z3 += ONE << (CONST_BITS-PASS1_BITS-1);
4614 z4 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
4615 z1 = MULTIPLY(z4, FIX(1.144122806)); /* c4 */
4616 z2 = MULTIPLY(z4, FIX(0.437016024)); /* c8 */
4617 tmp10 = z3 + z1;
4618 tmp11 = z3 - z2;
4619
4620 tmp22 = RIGHT_SHIFT(z3 - ((z1 - z2) << 1), /* c0 = (c4-c8)*2 */
4621 CONST_BITS-PASS1_BITS);
4622
4623 z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
4624 z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
4625
4626 z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c6 */
4627 tmp12 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c2-c6 */
4628 tmp13 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c2+c6 */
4629
4630 tmp20 = tmp10 + tmp12;
4631 tmp24 = tmp10 - tmp12;
4632 tmp21 = tmp11 + tmp13;
4633 tmp23 = tmp11 - tmp13;
4634
4635 /* Odd part */
4636
4637 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
4638 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
4639 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
4640 z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
4641
4642 tmp11 = z2 + z4;
4643 tmp13 = z2 - z4;
4644
4645 tmp12 = MULTIPLY(tmp13, FIX(0.309016994)); /* (c3-c7)/2 */
4646 z5 = z3 << CONST_BITS;
4647
4648 z2 = MULTIPLY(tmp11, FIX(0.951056516)); /* (c3+c7)/2 */
4649 z4 = z5 + tmp12;
4650
4651 tmp10 = MULTIPLY(z1, FIX(1.396802247)) + z2 + z4; /* c1 */
4652 tmp14 = MULTIPLY(z1, FIX(0.221231742)) - z2 + z4; /* c9 */
4653
4654 z2 = MULTIPLY(tmp11, FIX(0.587785252)); /* (c1-c9)/2 */
4655 z4 = z5 - tmp12 - (tmp13 << (CONST_BITS - 1));
4656
4657 tmp12 = (z1 - tmp13 - z3) << PASS1_BITS;
4658
4659 tmp11 = MULTIPLY(z1, FIX(1.260073511)) - z2 - z4; /* c3 */
4660 tmp13 = MULTIPLY(z1, FIX(0.642039522)) - z2 + z4; /* c7 */
4661
4662 /* Final output stage */
4663
4664 wsptr[5*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
4665 wsptr[5*9] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
4666 wsptr[5*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
4667 wsptr[5*8] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
4668 wsptr[5*2] = (int) (tmp22 + tmp12);
4669 wsptr[5*7] = (int) (tmp22 - tmp12);
4670 wsptr[5*3] = (int) RIGHT_SHIFT(tmp23 + tmp13, CONST_BITS-PASS1_BITS);
4671 wsptr[5*6] = (int) RIGHT_SHIFT(tmp23 - tmp13, CONST_BITS-PASS1_BITS);
4672 wsptr[5*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
4673 wsptr[5*5] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
4674 }
4675
4676 /* Pass 2: process 10 rows from work array, store into output array.
4677 * 5-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/10).
4678 */
4679 wsptr = workspace;
4680 for (ctr = 0; ctr < 10; ctr++) {
4681 outptr = output_buf[ctr] + output_col;
4682
4683 /* Even part */
4684
4685 /* Add fudge factor here for final descale. */
4686 tmp12 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
4687 tmp12 <<= CONST_BITS;
4688 tmp13 = (INT32) wsptr[2];
4689 tmp14 = (INT32) wsptr[4];
4690 z1 = MULTIPLY(tmp13 + tmp14, FIX(0.790569415)); /* (c2+c4)/2 */
4691 z2 = MULTIPLY(tmp13 - tmp14, FIX(0.353553391)); /* (c2-c4)/2 */
4692 z3 = tmp12 + z2;
4693 tmp10 = z3 + z1;
4694 tmp11 = z3 - z1;
4695 tmp12 -= z2 << 2;
4696
4697 /* Odd part */
4698
4699 z2 = (INT32) wsptr[1];
4700 z3 = (INT32) wsptr[3];
4701
4702 z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c3 */
4703 tmp13 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c1-c3 */
4704 tmp14 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c1+c3 */
4705
4706 /* Final output stage */
4707
4708 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp13,
4709 CONST_BITS+PASS1_BITS+3)
4710 & RANGE_MASK];
4711 outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp13,
4712 CONST_BITS+PASS1_BITS+3)
4713 & RANGE_MASK];
4714 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp14,
4715 CONST_BITS+PASS1_BITS+3)
4716 & RANGE_MASK];
4717 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp14,
4718 CONST_BITS+PASS1_BITS+3)
4719 & RANGE_MASK];
4720 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12,
4721 CONST_BITS+PASS1_BITS+3)
4722 & RANGE_MASK];
4723
4724 wsptr += 5; /* advance pointer to next row */
4725 }
4726 }
4727
4728
4729 /*
4730 * Perform dequantization and inverse DCT on one block of coefficients,
4731 * producing a 4x8 output block.
4732 *
4733 * 8-point IDCT in pass 1 (columns), 4-point in pass 2 (rows).
4734 */
4735
4736 GLOBAL(void)
4737 jpeg_idct_4x8 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
4738 JCOEFPTR coef_block,
4739 JSAMPARRAY output_buf, JDIMENSION output_col)
4740 {
4741 INT32 tmp0, tmp1, tmp2, tmp3;
4742 INT32 tmp10, tmp11, tmp12, tmp13;
4743 INT32 z1, z2, z3;
4744 JCOEFPTR inptr;
4745 ISLOW_MULT_TYPE * quantptr;
4746 int * wsptr;
4747 JSAMPROW outptr;
4748 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
4749 int ctr;
4750 int workspace[4*8]; /* buffers data between passes */
4751 SHIFT_TEMPS
4752
4753 /* Pass 1: process columns from input, store into work array. */
4754 /* Note results are scaled up by sqrt(8) compared to a true IDCT; */
4755 /* furthermore, we scale the results by 2**PASS1_BITS. */
4756
4757 inptr = coef_block;
4758 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
4759 wsptr = workspace;
4760 for (ctr = 4; ctr > 0; ctr--) {
4761 /* Due to quantization, we will usually find that many of the input
4762 * coefficients are zero, especially the AC terms. We can exploit this
4763 * by short-circuiting the IDCT calculation for any column in which all
4764 * the AC terms are zero. In that case each output is equal to the
4765 * DC coefficient (with scale factor as needed).
4766 * With typical images and quantization tables, half or more of the
4767 * column DCT calculations can be simplified this way.
4768 */
4769
4770 if (inptr[DCTSIZE*1] == 0 && inptr[DCTSIZE*2] == 0 &&
4771 inptr[DCTSIZE*3] == 0 && inptr[DCTSIZE*4] == 0 &&
4772 inptr[DCTSIZE*5] == 0 && inptr[DCTSIZE*6] == 0 &&
4773 inptr[DCTSIZE*7] == 0) {
4774 /* AC terms all zero */
4775 int dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]) << PASS1_BITS;
4776
4777 wsptr[4*0] = dcval;
4778 wsptr[4*1] = dcval;
4779 wsptr[4*2] = dcval;
4780 wsptr[4*3] = dcval;
4781 wsptr[4*4] = dcval;
4782 wsptr[4*5] = dcval;
4783 wsptr[4*6] = dcval;
4784 wsptr[4*7] = dcval;
4785
4786 inptr++; /* advance pointers to next column */
4787 quantptr++;
4788 wsptr++;
4789 continue;
4790 }
4791
4792 /* Even part: reverse the even part of the forward DCT. */
4793 /* The rotator is sqrt(2)*c(-6). */
4794
4795 z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
4796 z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
4797
4798 z1 = MULTIPLY(z2 + z3, FIX_0_541196100);
4799 tmp2 = z1 + MULTIPLY(z2, FIX_0_765366865);
4800 tmp3 = z1 - MULTIPLY(z3, FIX_1_847759065);
4801
4802 z2 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
4803 z3 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
4804 z2 <<= CONST_BITS;
4805 z3 <<= CONST_BITS;
4806 /* Add fudge factor here for final descale. */
4807 z2 += ONE << (CONST_BITS-PASS1_BITS-1);
4808
4809 tmp0 = z2 + z3;
4810 tmp1 = z2 - z3;
4811
4812 tmp10 = tmp0 + tmp2;
4813 tmp13 = tmp0 - tmp2;
4814 tmp11 = tmp1 + tmp3;
4815 tmp12 = tmp1 - tmp3;
4816
4817 /* Odd part per figure 8; the matrix is unitary and hence its
4818 * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively.
4819 */
4820
4821 tmp0 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
4822 tmp1 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
4823 tmp2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
4824 tmp3 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
4825
4826 z2 = tmp0 + tmp2;
4827 z3 = tmp1 + tmp3;
4828
4829 z1 = MULTIPLY(z2 + z3, FIX_1_175875602); /* sqrt(2) * c3 */
4830 z2 = MULTIPLY(z2, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
4831 z3 = MULTIPLY(z3, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
4832 z2 += z1;
4833 z3 += z1;
4834
4835 z1 = MULTIPLY(tmp0 + tmp3, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */
4836 tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
4837 tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */
4838 tmp0 += z1 + z2;
4839 tmp3 += z1 + z3;
4840
4841 z1 = MULTIPLY(tmp1 + tmp2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
4842 tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
4843 tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
4844 tmp1 += z1 + z3;
4845 tmp2 += z1 + z2;
4846
4847 /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */
4848
4849 wsptr[4*0] = (int) RIGHT_SHIFT(tmp10 + tmp3, CONST_BITS-PASS1_BITS);
4850 wsptr[4*7] = (int) RIGHT_SHIFT(tmp10 - tmp3, CONST_BITS-PASS1_BITS);
4851 wsptr[4*1] = (int) RIGHT_SHIFT(tmp11 + tmp2, CONST_BITS-PASS1_BITS);
4852 wsptr[4*6] = (int) RIGHT_SHIFT(tmp11 - tmp2, CONST_BITS-PASS1_BITS);
4853 wsptr[4*2] = (int) RIGHT_SHIFT(tmp12 + tmp1, CONST_BITS-PASS1_BITS);
4854 wsptr[4*5] = (int) RIGHT_SHIFT(tmp12 - tmp1, CONST_BITS-PASS1_BITS);
4855 wsptr[4*3] = (int) RIGHT_SHIFT(tmp13 + tmp0, CONST_BITS-PASS1_BITS);
4856 wsptr[4*4] = (int) RIGHT_SHIFT(tmp13 - tmp0, CONST_BITS-PASS1_BITS);
4857
4858 inptr++; /* advance pointers to next column */
4859 quantptr++;
4860 wsptr++;
4861 }
4862
4863 /* Pass 2: process 8 rows from work array, store into output array.
4864 * 4-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/16).
4865 */
4866 wsptr = workspace;
4867 for (ctr = 0; ctr < 8; ctr++) {
4868 outptr = output_buf[ctr] + output_col;
4869
4870 /* Even part */
4871
4872 /* Add fudge factor here for final descale. */
4873 tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
4874 tmp2 = (INT32) wsptr[2];
4875
4876 tmp10 = (tmp0 + tmp2) << CONST_BITS;
4877 tmp12 = (tmp0 - tmp2) << CONST_BITS;
4878
4879 /* Odd part */
4880 /* Same rotation as in the even part of the 8x8 LL&M IDCT */
4881
4882 z2 = (INT32) wsptr[1];
4883 z3 = (INT32) wsptr[3];
4884
4885 z1 = MULTIPLY(z2 + z3, FIX_0_541196100); /* c6 */
4886 tmp0 = z1 + MULTIPLY(z2, FIX_0_765366865); /* c2-c6 */
4887 tmp2 = z1 - MULTIPLY(z3, FIX_1_847759065); /* c2+c6 */
4888
4889 /* Final output stage */
4890
4891 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
4892 CONST_BITS+PASS1_BITS+3)
4893 & RANGE_MASK];
4894 outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
4895 CONST_BITS+PASS1_BITS+3)
4896 & RANGE_MASK];
4897 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp2,
4898 CONST_BITS+PASS1_BITS+3)
4899 & RANGE_MASK];
4900 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp2,
4901 CONST_BITS+PASS1_BITS+3)
4902 & RANGE_MASK];
4903
4904 wsptr += 4; /* advance pointer to next row */
4905 }
4906 }
4907
4908
4909 /*
4910 * Perform dequantization and inverse DCT on one block of coefficients,
4911 * producing a reduced-size 3x6 output block.
4912 *
4913 * 6-point IDCT in pass 1 (columns), 3-point in pass 2 (rows).
4914 */
4915
4916 GLOBAL(void)
4917 jpeg_idct_3x6 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
4918 JCOEFPTR coef_block,
4919 JSAMPARRAY output_buf, JDIMENSION output_col)
4920 {
4921 INT32 tmp0, tmp1, tmp2, tmp10, tmp11, tmp12;
4922 INT32 z1, z2, z3;
4923 JCOEFPTR inptr;
4924 ISLOW_MULT_TYPE * quantptr;
4925 int * wsptr;
4926 JSAMPROW outptr;
4927 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
4928 int ctr;
4929 int workspace[3*6]; /* buffers data between passes */
4930 SHIFT_TEMPS
4931
4932 /* Pass 1: process columns from input, store into work array.
4933 * 6-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/12).
4934 */
4935 inptr = coef_block;
4936 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
4937 wsptr = workspace;
4938 for (ctr = 0; ctr < 3; ctr++, inptr++, quantptr++, wsptr++) {
4939 /* Even part */
4940
4941 tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
4942 tmp0 <<= CONST_BITS;
4943 /* Add fudge factor here for final descale. */
4944 tmp0 += ONE << (CONST_BITS-PASS1_BITS-1);
4945 tmp2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
4946 tmp10 = MULTIPLY(tmp2, FIX(0.707106781)); /* c4 */
4947 tmp1 = tmp0 + tmp10;
4948 tmp11 = RIGHT_SHIFT(tmp0 - tmp10 - tmp10, CONST_BITS-PASS1_BITS);
4949 tmp10 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
4950 tmp0 = MULTIPLY(tmp10, FIX(1.224744871)); /* c2 */
4951 tmp10 = tmp1 + tmp0;
4952 tmp12 = tmp1 - tmp0;
4953
4954 /* Odd part */
4955
4956 z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
4957 z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
4958 z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
4959 tmp1 = MULTIPLY(z1 + z3, FIX(0.366025404)); /* c5 */
4960 tmp0 = tmp1 + ((z1 + z2) << CONST_BITS);
4961 tmp2 = tmp1 + ((z3 - z2) << CONST_BITS);
4962 tmp1 = (z1 - z2 - z3) << PASS1_BITS;
4963
4964 /* Final output stage */
4965
4966 wsptr[3*0] = (int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS-PASS1_BITS);
4967 wsptr[3*5] = (int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS-PASS1_BITS);
4968 wsptr[3*1] = (int) (tmp11 + tmp1);
4969 wsptr[3*4] = (int) (tmp11 - tmp1);
4970 wsptr[3*2] = (int) RIGHT_SHIFT(tmp12 + tmp2, CONST_BITS-PASS1_BITS);
4971 wsptr[3*3] = (int) RIGHT_SHIFT(tmp12 - tmp2, CONST_BITS-PASS1_BITS);
4972 }
4973
4974 /* Pass 2: process 6 rows from work array, store into output array.
4975 * 3-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/6).
4976 */
4977 wsptr = workspace;
4978 for (ctr = 0; ctr < 6; ctr++) {
4979 outptr = output_buf[ctr] + output_col;
4980
4981 /* Even part */
4982
4983 /* Add fudge factor here for final descale. */
4984 tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
4985 tmp0 <<= CONST_BITS;
4986 tmp2 = (INT32) wsptr[2];
4987 tmp12 = MULTIPLY(tmp2, FIX(0.707106781)); /* c2 */
4988 tmp10 = tmp0 + tmp12;
4989 tmp2 = tmp0 - tmp12 - tmp12;
4990
4991 /* Odd part */
4992
4993 tmp12 = (INT32) wsptr[1];
4994 tmp0 = MULTIPLY(tmp12, FIX(1.224744871)); /* c1 */
4995
4996 /* Final output stage */
4997
4998 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
4999 CONST_BITS+PASS1_BITS+3)
5000 & RANGE_MASK];
5001 outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
5002 CONST_BITS+PASS1_BITS+3)
5003 & RANGE_MASK];
5004 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp2,
5005 CONST_BITS+PASS1_BITS+3)
5006 & RANGE_MASK];
5007
5008 wsptr += 3; /* advance pointer to next row */
5009 }
5010 }
5011
5012
5013 /*
5014 * Perform dequantization and inverse DCT on one block of coefficients,
5015 * producing a 2x4 output block.
5016 *
5017 * 4-point IDCT in pass 1 (columns), 2-point in pass 2 (rows).
5018 */
5019
5020 GLOBAL(void)
5021 jpeg_idct_2x4 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
5022 JCOEFPTR coef_block,
5023 JSAMPARRAY output_buf, JDIMENSION output_col)
5024 {
5025 INT32 tmp0, tmp2, tmp10, tmp12;
5026 INT32 z1, z2, z3;
5027 JCOEFPTR inptr;
5028 ISLOW_MULT_TYPE * quantptr;
5029 INT32 * wsptr;
5030 JSAMPROW outptr;
5031 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
5032 int ctr;
5033 INT32 workspace[2*4]; /* buffers data between passes */
5034 SHIFT_TEMPS
5035
5036 /* Pass 1: process columns from input, store into work array.
5037 * 4-point IDCT kernel,
5038 * cK represents sqrt(2) * cos(K*pi/16) [refers to 8-point IDCT].
5039 */
5040 inptr = coef_block;
5041 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
5042 wsptr = workspace;
5043 for (ctr = 0; ctr < 2; ctr++, inptr++, quantptr++, wsptr++) {
5044 /* Even part */
5045
5046 tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
5047 tmp2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
5048
5049 tmp10 = (tmp0 + tmp2) << CONST_BITS;
5050 tmp12 = (tmp0 - tmp2) << CONST_BITS;
5051
5052 /* Odd part */
5053 /* Same rotation as in the even part of the 8x8 LL&M IDCT */
5054
5055 z2 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
5056 z3 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
5057
5058 z1 = MULTIPLY(z2 + z3, FIX_0_541196100); /* c6 */
5059 tmp0 = z1 + MULTIPLY(z2, FIX_0_765366865); /* c2-c6 */
5060 tmp2 = z1 - MULTIPLY(z3, FIX_1_847759065); /* c2+c6 */
5061
5062 /* Final output stage */
5063
5064 wsptr[2*0] = tmp10 + tmp0;
5065 wsptr[2*3] = tmp10 - tmp0;
5066 wsptr[2*1] = tmp12 + tmp2;
5067 wsptr[2*2] = tmp12 - tmp2;
5068 }
5069
5070 /* Pass 2: process 4 rows from work array, store into output array. */
5071
5072 wsptr = workspace;
5073 for (ctr = 0; ctr < 4; ctr++) {
5074 outptr = output_buf[ctr] + output_col;
5075
5076 /* Even part */
5077
5078 /* Add fudge factor here for final descale. */
5079 tmp10 = wsptr[0] + (ONE << (CONST_BITS+2));
5080
5081 /* Odd part */
5082
5083 tmp0 = wsptr[1];
5084
5085 /* Final output stage */
5086
5087 outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS+3)
5088 & RANGE_MASK];
5089 outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS+3)
5090 & RANGE_MASK];
5091
5092 wsptr += 2; /* advance pointer to next row */
5093 }
5094 }
5095
5096
5097 /*
5098 * Perform dequantization and inverse DCT on one block of coefficients,
5099 * producing a 1x2 output block.
5100 *
5101 * 2-point IDCT in pass 1 (columns), 1-point in pass 2 (rows).
5102 */
5103
5104 GLOBAL(void)
5105 jpeg_idct_1x2 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
5106 JCOEFPTR coef_block,
5107 JSAMPARRAY output_buf, JDIMENSION output_col)
5108 {
5109 INT32 tmp0, tmp10;
5110 ISLOW_MULT_TYPE * quantptr;
5111 JSAMPLE *range_limit = IDCT_range_limit(cinfo);
5112 SHIFT_TEMPS
5113
5114 /* Process 1 column from input, store into output array. */
5115
5116 quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
5117
5118 /* Even part */
5119
5120 tmp10 = DEQUANTIZE(coef_block[DCTSIZE*0], quantptr[DCTSIZE*0]);
5121 /* Add fudge factor here for final descale. */
5122 tmp10 += ONE << 2;
5123
5124 /* Odd part */
5125
5126 tmp0 = DEQUANTIZE(coef_block[DCTSIZE*1], quantptr[DCTSIZE*1]);
5127
5128 /* Final output stage */
5129
5130 output_buf[0][output_col] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0, 3)
5131 & RANGE_MASK];
5132 output_buf[1][output_col] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0, 3)
5133 & RANGE_MASK];
5134 }
5135
5136 #endif /* IDCT_SCALING_SUPPORTED */
5137 #endif /* DCT_ISLOW_SUPPORTED */