Improve performance a bit for the non-SIMD case
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@471 632fc199-4ca6-4c93-a231-07263d6284db
diff --git a/jccolor.c b/jccolor.c
index 5e1c180..9559aa5 100644
--- a/jccolor.c
+++ b/jccolor.c
@@ -3,7 +3,7 @@
*
* Copyright (C) 1991-1996, Thomas G. Lane.
* Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
- * Copyright 2009 D. R. Commander
+ * Copyright 2009-2011 D. R. Commander
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
@@ -141,6 +141,10 @@
register JSAMPROW outptr0, outptr1, outptr2;
register JDIMENSION col;
JDIMENSION num_cols = cinfo->image_width;
+ int rindex = rgb_red[cinfo->in_color_space];
+ int gindex = rgb_green[cinfo->in_color_space];
+ int bindex = rgb_blue[cinfo->in_color_space];
+ int rgbstride = rgb_pixelsize[cinfo->in_color_space];
while (--num_rows >= 0) {
inptr = *input_buf++;
@@ -149,10 +153,10 @@
outptr2 = output_buf[2][output_row];
output_row++;
for (col = 0; col < num_cols; col++) {
- r = GETJSAMPLE(inptr[rgb_red[cinfo->in_color_space]]);
- g = GETJSAMPLE(inptr[rgb_green[cinfo->in_color_space]]);
- b = GETJSAMPLE(inptr[rgb_blue[cinfo->in_color_space]]);
- inptr += rgb_pixelsize[cinfo->in_color_space];
+ r = GETJSAMPLE(inptr[rindex]);
+ g = GETJSAMPLE(inptr[gindex]);
+ b = GETJSAMPLE(inptr[bindex]);
+ inptr += rgbstride;
/* If the inputs are 0..MAXJSAMPLE, the outputs of these equations
* must be too; we do not need an explicit range-limiting operation.
* Hence the value being shifted is never negative, and we don't
@@ -197,16 +201,20 @@
register JSAMPROW outptr;
register JDIMENSION col;
JDIMENSION num_cols = cinfo->image_width;
+ int rindex = rgb_red[cinfo->in_color_space];
+ int gindex = rgb_green[cinfo->in_color_space];
+ int bindex = rgb_blue[cinfo->in_color_space];
+ int rgbstride = rgb_pixelsize[cinfo->in_color_space];
while (--num_rows >= 0) {
inptr = *input_buf++;
outptr = output_buf[0][output_row];
output_row++;
for (col = 0; col < num_cols; col++) {
- r = GETJSAMPLE(inptr[rgb_red[cinfo->in_color_space]]);
- g = GETJSAMPLE(inptr[rgb_green[cinfo->in_color_space]]);
- b = GETJSAMPLE(inptr[rgb_blue[cinfo->in_color_space]]);
- inptr += rgb_pixelsize[cinfo->in_color_space];
+ r = GETJSAMPLE(inptr[rindex]);
+ g = GETJSAMPLE(inptr[gindex]);
+ b = GETJSAMPLE(inptr[bindex]);
+ inptr += rgbstride;
/* Y */
outptr[col] = (JSAMPLE)
((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])