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modules/javafx.graphics/src/main/native-iio/libjpeg7/jcdctmgr.c

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@@ -1,9 +1,10 @@
 /*
  * jcdctmgr.c
  *
  * Copyright (C) 1994-1996, Thomas G. Lane.
+ * Modified 2003-2013 by Guido Vollbeding.
  * This file is part of the Independent JPEG Group's software.
  * For conditions of distribution and use, see the accompanying README file.
  *
  * This file contains the forward-DCT management logic.
  * This code selects a particular DCT implementation to be used,

@@ -23,26 +24,34 @@
   struct jpeg_forward_dct pub;  /* public fields */
 
   /* Pointer to the DCT routine actually in use */
   forward_DCT_method_ptr do_dct[MAX_COMPONENTS];
 
-  /* The actual post-DCT divisors --- not identical to the quant table
-   * entries, because of scaling (especially for an unnormalized DCT).
-   * Each table is given in normal array order.
-   */
-  DCTELEM * divisors[NUM_QUANT_TBLS];
-
 #ifdef DCT_FLOAT_SUPPORTED
   /* Same as above for the floating-point case. */
   float_DCT_method_ptr do_float_dct[MAX_COMPONENTS];
-  FAST_FLOAT * float_divisors[NUM_QUANT_TBLS];
 #endif
 } my_fdct_controller;
 
 typedef my_fdct_controller * my_fdct_ptr;
 
 
+/* The allocated post-DCT divisor tables -- big enough for any
+ * supported variant and not identical to the quant table entries,
+ * because of scaling (especially for an unnormalized DCT) --
+ * are pointed to by dct_table in the per-component comp_info
+ * structures.  Each table is given in normal array order.
+ */
+
+typedef union {
+  DCTELEM int_array[DCTSIZE2];
+#ifdef DCT_FLOAT_SUPPORTED
+  FAST_FLOAT float_array[DCTSIZE2];
+#endif
+} divisor_table;
+
+
 /* The current scaled-DCT routines require ISLOW-style divisor tables,
  * so be sure to compile that code if either ISLOW or SCALING is requested.
  */
 #ifdef DCT_ISLOW_SUPPORTED
 #define PROVIDE_ISLOW_TABLES

@@ -69,11 +78,11 @@
 /* This version is used for integer DCT implementations. */
 {
   /* This routine is heavily used, so it's worth coding it tightly. */
   my_fdct_ptr fdct = (my_fdct_ptr) cinfo->fdct;
   forward_DCT_method_ptr do_dct = fdct->do_dct[compptr->component_index];
-  DCTELEM * divisors = fdct->divisors[compptr->quant_tbl_no];
+  DCTELEM * divisors = (DCTELEM *) compptr->dct_table;
   DCTELEM workspace[DCTSIZE2];  /* work area for FDCT subroutine */
   JDIMENSION bi;
 
   sample_data += start_row;     /* fold in the vertical offset once */
 

@@ -132,11 +141,11 @@
 /* This version is used for floating-point DCT implementations. */
 {
   /* This routine is heavily used, so it's worth coding it tightly. */
   my_fdct_ptr fdct = (my_fdct_ptr) cinfo->fdct;
   float_DCT_method_ptr do_dct = fdct->do_float_dct[compptr->component_index];
-  FAST_FLOAT * divisors = fdct->float_divisors[compptr->quant_tbl_no];
+  FAST_FLOAT * divisors = (FAST_FLOAT *) compptr->dct_table;
   FAST_FLOAT workspace[DCTSIZE2]; /* work area for FDCT subroutine */
   JDIMENSION bi;
 
   sample_data += start_row;     /* fold in the vertical offset once */
 

@@ -350,26 +359,21 @@
     /* Make sure specified quantization table is present */
     if (qtblno < 0 || qtblno >= NUM_QUANT_TBLS ||
         cinfo->quant_tbl_ptrs[qtblno] == NULL)
       ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, qtblno);
     qtbl = cinfo->quant_tbl_ptrs[qtblno];
-    /* Compute divisors for this quant table */
-    /* We may do this more than once for same table, but it's not a big deal */
+    /* Create divisor table from quant table */
     switch (method) {
 #ifdef PROVIDE_ISLOW_TABLES
     case JDCT_ISLOW:
       /* For LL&M IDCT method, divisors are equal to raw quantization
        * coefficients multiplied by 8 (to counteract scaling).
        */
-      if (fdct->divisors[qtblno] == NULL) {
-        fdct->divisors[qtblno] = (DCTELEM *)
-          (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
-                                      DCTSIZE2 * SIZEOF(DCTELEM));
-      }
-      dtbl = fdct->divisors[qtblno];
+      dtbl = (DCTELEM *) compptr->dct_table;
       for (i = 0; i < DCTSIZE2; i++) {
-        dtbl[i] = ((DCTELEM) qtbl->quantval[i]) << 3;
+        dtbl[i] =
+          ((DCTELEM) qtbl->quantval[i]) << (compptr->component_needed ? 4 : 3);
       }
       fdct->pub.forward_DCT[ci] = forward_DCT;
       break;
 #endif
 #ifdef DCT_IFAST_SUPPORTED

@@ -393,21 +397,16 @@
            8867, 12299, 11585, 10426,  8867,  6967,  4799,  2446,
            4520,  6270,  5906,  5315,  4520,  3552,  2446,  1247
         };
         SHIFT_TEMPS
 
-        if (fdct->divisors[qtblno] == NULL) {
-          fdct->divisors[qtblno] = (DCTELEM *)
-            (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
-                                        DCTSIZE2 * SIZEOF(DCTELEM));
-        }
-        dtbl = fdct->divisors[qtblno];
+        dtbl = (DCTELEM *) compptr->dct_table;
         for (i = 0; i < DCTSIZE2; i++) {
           dtbl[i] = (DCTELEM)
             DESCALE(MULTIPLY16V16((INT32) qtbl->quantval[i],
                                   (INT32) aanscales[i]),
-                    CONST_BITS-3);
+                    compptr->component_needed ? CONST_BITS-4 : CONST_BITS-3);
         }
       }
       fdct->pub.forward_DCT[ci] = forward_DCT;
       break;
 #endif

@@ -420,29 +419,24 @@
          *   scalefactor[k] = cos(k*PI/16) * sqrt(2)    for k=1..7
          * We apply a further scale factor of 8.
          * What's actually stored is 1/divisor so that the inner loop can
          * use a multiplication rather than a division.
          */
-        FAST_FLOAT * fdtbl;
+        FAST_FLOAT * fdtbl = (FAST_FLOAT *) compptr->dct_table;
         int row, col;
         static const double aanscalefactor[DCTSIZE] = {
           1.0, 1.387039845, 1.306562965, 1.175875602,
           1.0, 0.785694958, 0.541196100, 0.275899379
         };
 
-        if (fdct->float_divisors[qtblno] == NULL) {
-          fdct->float_divisors[qtblno] = (FAST_FLOAT *)
-            (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
-                                        DCTSIZE2 * SIZEOF(FAST_FLOAT));
-        }
-        fdtbl = fdct->float_divisors[qtblno];
         i = 0;
         for (row = 0; row < DCTSIZE; row++) {
           for (col = 0; col < DCTSIZE; col++) {
             fdtbl[i] = (FAST_FLOAT)
-              (1.0 / (((double) qtbl->quantval[i] *
-                       aanscalefactor[row] * aanscalefactor[col] * 8.0)));
+              (1.0 / ((double) qtbl->quantval[i] *
+                      aanscalefactor[row] * aanscalefactor[col] *
+                      (compptr->component_needed ? 16.0 : 8.0)));
             i++;
           }
         }
       }
       fdct->pub.forward_DCT[ci] = forward_DCT_float;

@@ -462,21 +456,22 @@
 
 GLOBAL(void)
 jinit_forward_dct (j_compress_ptr cinfo)
 {
   my_fdct_ptr fdct;
-  int i;
+  int ci;
+  jpeg_component_info *compptr;
 
   fdct = (my_fdct_ptr)
     (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
                                 SIZEOF(my_fdct_controller));
-  cinfo->fdct = (struct jpeg_forward_dct *) fdct;
+  cinfo->fdct = &fdct->pub;
   fdct->pub.start_pass = start_pass_fdctmgr;
 
-  /* Mark divisor tables unallocated */
-  for (i = 0; i < NUM_QUANT_TBLS; i++) {
-    fdct->divisors[i] = NULL;
-#ifdef DCT_FLOAT_SUPPORTED
-    fdct->float_divisors[i] = NULL;
-#endif
+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
+       ci++, compptr++) {
+    /* Allocate a divisor table for each component */
+    compptr->dct_table =
+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
+                                  SIZEOF(divisor_table));
   }
 }
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