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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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