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

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*** 1,10 **** /* * jfdctfst.c * * Copyright (C) 1994-1996, Thomas G. Lane. ! * Modified 2003-2009 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 a fast, not so accurate integer implementation of the * forward DCT (Discrete Cosine Transform). --- 1,10 ---- /* * jfdctfst.c * * Copyright (C) 1994-1996, Thomas G. Lane. ! * Modified 2003-2017 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 a fast, not so accurate integer implementation of the * forward DCT (Discrete Cosine Transform).
*** 42,52 **** /* * This module is specialized to the case DCTSIZE = 8. */ #if DCTSIZE != 8 ! Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */ #endif /* Scaling decisions are generally the same as in the LL&M algorithm; * see jfdctint.c for more details. However, we choose to descale --- 42,52 ---- /* * This module is specialized to the case DCTSIZE = 8. */ #if DCTSIZE != 8 ! Sorry, this code only copes with 8x8 DCT blocks. /* deliberate syntax err */ #endif /* Scaling decisions are generally the same as in the LL&M algorithm; * see jfdctint.c for more details. However, we choose to descale
*** 107,116 **** --- 107,118 ---- #define MULTIPLY(var,const) ((DCTELEM) DESCALE((var) * (const), CONST_BITS)) /* * Perform the forward DCT on one block of samples. + * + * cK represents cos(K*pi/16). */ GLOBAL(void) jpeg_fdct_ifast (DCTELEM * data, JSAMPARRAY sample_data, JDIMENSION start_col) {
*** 143,153 **** tmp10 = tmp0 + tmp3; /* phase 2 */ tmp13 = tmp0 - tmp3; tmp11 = tmp1 + tmp2; tmp12 = tmp1 - tmp2; ! /* Apply unsigned->signed conversion */ dataptr[0] = tmp10 + tmp11 - 8 * CENTERJSAMPLE; /* phase 3 */ dataptr[4] = tmp10 - tmp11; z1 = MULTIPLY(tmp12 + tmp13, FIX_0_707106781); /* c4 */ dataptr[2] = tmp13 + z1; /* phase 5 */ --- 145,155 ---- tmp10 = tmp0 + tmp3; /* phase 2 */ tmp13 = tmp0 - tmp3; tmp11 = tmp1 + tmp2; tmp12 = tmp1 - tmp2; ! /* Apply unsigned->signed conversion. */ dataptr[0] = tmp10 + tmp11 - 8 * CENTERJSAMPLE; /* phase 3 */ dataptr[4] = tmp10 - tmp11; z1 = MULTIPLY(tmp12 + tmp13, FIX_0_707106781); /* c4 */ dataptr[2] = tmp13 + z1; /* phase 5 */
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