diff options
Diffstat (limited to 'jpeg/jdmerge.c')
| -rw-r--r-- | jpeg/jdmerge.c | 31 |
1 files changed, 15 insertions, 16 deletions
diff --git a/jpeg/jdmerge.c b/jpeg/jdmerge.c index 8ff13143a..0d16821be 100644 --- a/jpeg/jdmerge.c +++ b/jpeg/jdmerge.c @@ -2,7 +2,7 @@ * jdmerge.c * * Copyright (C) 1994-1996, Thomas G. Lane. - * Modified 2013-2020 by Guido Vollbeding. + * Modified 2013-2022 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. * @@ -20,17 +20,17 @@ * B = Y + K4 * Cb * only the Y term varies among the group of pixels corresponding to a pair * of chroma samples, so the rest of the terms can be calculated just once. - * At typical sampling ratios, this eliminates half or three-quarters of the - * multiplications needed for color conversion. + * At typical sampling ratios, this eliminates half or three-quarters + * of the multiplications needed for color conversion. * * This file currently provides implementations for the following cases: * YCC => RGB color conversion only (YCbCr or BG_YCC). * Sampling ratios of 2h1v or 2h2v. * No scaling needed at upsample time. * Corner-aligned (non-CCIR601) sampling alignment. - * Other special cases could be added, but in most applications these are - * the only common cases. (For uncommon cases we fall back on the more - * general code in jdsample.c and jdcolor.c.) + * Other special cases could be added, but in most applications these + * are the only common cases. (For uncommon cases we fall back on + * the more general code in jdsample.c and jdcolor.c.) */ #define JPEG_INTERNALS @@ -286,9 +286,9 @@ h2v1_merged_upsample (j_decompress_ptr cinfo, /* Do the chroma part of the calculation */ cb = GETJSAMPLE(*inptr1++); cr = GETJSAMPLE(*inptr2++); - cred = Crrtab[cr]; cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS); cblue = Cbbtab[cb]; + cred = Crrtab[cr]; /* Fetch 2 Y values and emit 2 pixels */ y = GETJSAMPLE(*inptr0++); outptr[RGB_RED] = range_limit[y + cred]; @@ -303,15 +303,14 @@ h2v1_merged_upsample (j_decompress_ptr cinfo, } /* If image width is odd, do the last output column separately */ if (cinfo->output_width & 1) { + y = GETJSAMPLE(*inptr0); cb = GETJSAMPLE(*inptr1); cr = GETJSAMPLE(*inptr2); - cred = Crrtab[cr]; - cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS); - cblue = Cbbtab[cb]; - y = GETJSAMPLE(*inptr0); - outptr[RGB_RED] = range_limit[y + cred]; - outptr[RGB_GREEN] = range_limit[y + cgreen]; - outptr[RGB_BLUE] = range_limit[y + cblue]; + outptr[RGB_RED] = range_limit[y + Crrtab[cr]]; + outptr[RGB_GREEN] = range_limit[y + + ((int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], + SCALEBITS))]; + outptr[RGB_BLUE] = range_limit[y + Cbbtab[cb]]; } } @@ -350,9 +349,9 @@ h2v2_merged_upsample (j_decompress_ptr cinfo, /* Do the chroma part of the calculation */ cb = GETJSAMPLE(*inptr1++); cr = GETJSAMPLE(*inptr2++); - cred = Crrtab[cr]; cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS); cblue = Cbbtab[cb]; + cred = Crrtab[cr]; /* Fetch 4 Y values and emit 4 pixels */ y = GETJSAMPLE(*inptr00++); outptr0[RGB_RED] = range_limit[y + cred]; @@ -379,9 +378,9 @@ h2v2_merged_upsample (j_decompress_ptr cinfo, if (cinfo->output_width & 1) { cb = GETJSAMPLE(*inptr1); cr = GETJSAMPLE(*inptr2); - cred = Crrtab[cr]; cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS); cblue = Cbbtab[cb]; + cred = Crrtab[cr]; y = GETJSAMPLE(*inptr00); outptr0[RGB_RED] = range_limit[y + cred]; outptr0[RGB_GREEN] = range_limit[y + cgreen]; |