mewin/libpng
1
0
Fork 0
mirror of https://git.code.sf.net/p/libpng/code.git synced 2025-07-10 18:04:09 +02:00
Code Issues Projects Releases Wiki Activity

Imported from libpng-1.2.6rc3.tar

Browse Source
This commit is contained in:
Glenn Randers-Pehrson
2004-08-09 21:50:32 -05:00
parent dff799ef89
commit d029a75d4f
56 changed files with 225 additions and 167 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
pngrtran.c
View File

@@ -1,7 +1,7 @@
/* pngrtran.c - transforms the data in a row for PNG readers
*
* libpng version 1.2.6rc2 - August 8, 2004
* libpng version 1.2.6rc3 - August 10, 2004
* For conditions of distribution and use, see copyright notice in png.h
* Copyright (c) 1998-2004 Glenn Randers-Pehrson
* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -482,12 +482,14 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
for (ir = 0; ir < num_red; ir++)
{
int dr = abs(ir - r);
/* int dr = abs(ir - r); */
int dr = ((ir > r) ? ir - r : r - ir);
int index_r = (ir << (PNG_DITHER_BLUE_BITS + PNG_DITHER_GREEN_BITS));
for (ig = 0; ig < num_green; ig++)
{
int dg = abs(ig - g);
/* int dg = abs(ig - g); */
int dg = ((ig > g) ? ig - g : g - ig);
int dt = dr + dg;
int dm = ((dr > dg) ? dr : dg);
int index_g = index_r | (ig << PNG_DITHER_BLUE_BITS);
@@ -495,7 +497,8 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
for (ib = 0; ib < num_blue; ib++)
{
int d_index = index_g | ib;
int db = abs(ib - b);
/* int db = abs(ib - b); */
int db = ((ib > b) ? ib - b : b - ib);
int dmax = ((dm > db) ? dm : db);
int d = dmax + dt + db;