Your message dated Wed, 16 Dec 2015 05:20:36 +0100
with message-id <5670e694.8080...@debian.org>
and subject line Re: libgif4: DGifSlurp() decodes interlaced images incorrectly
has caused the Debian Bug report #637078,
regarding libgif4: DGifSlurp() decodes interlaced images incorrectly
to be marked as done.
This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
Bug report if necessary, and/or fix the problem forthwith.
(NB: If you are a system administrator and have no idea what this
message is talking about, this may indicate a serious mail system
misconfiguration somewhere. Please contact ow...@bugs.debian.org
immediately.)
--
637078: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=637078
Debian Bug Tracking System
Contact ow...@bugs.debian.org with problems
--- Begin Message ---
Package: libgif4
Version: 4.1.6-9
Severity: normal
Tags: patch
DGifSlurp ignores interlace flag and treat an interlaced image as
a normal image.
-- System Information:
Debian Release: wheezy/sid
APT prefers unstable
APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Kernel: Linux 3.0.0 (SMP w/4 CPU cores)
Locale: LANG=ja_JP.eucJP, LC_CTYPE=ja_JP.eucJP (charmap=EUC-JP)
Shell: /bin/sh linked to /bin/dash
Versions of packages libgif4 depends on:
ii libc6 2.13-14 Embedded GNU C Library: Shared lib
libgif4 recommends no packages.
libgif4 suggests no packages.
-- no debconf information
#include <gif_lib.h>
#include <stdlib.h>
#include <X11/Xlib.h>
int main(int argc, char **argv)
{
GifFileType *gif;
ColorMapObject *cmap;
XImage img;
int image_size, i;
XSetWindowAttributes attr;
Display *display;
Window window;
if (argc < 2)
{
return 0;
}
gif = DGifOpenFileName(argv[1]);
if (gif == NULL)
{
return 1;
}
if (DGifSlurp(gif) != GIF_OK)
{
return 1;
}
cmap = gif->SavedImages[0].ImageDesc.ColorMap;
if (cmap == NULL)
{
cmap = gif->SColorMap;
}
img.width = gif->SavedImages[0].ImageDesc.Width;
img.height = gif->SavedImages[0].ImageDesc.Height;
img.xoffset = 0;
img.format = ZPixmap;
img.byte_order = MSBFirst;
img.bitmap_unit = 8;
img.bitmap_pad = 8;
img.depth = 24;
img.bytes_per_line = 0;
img.bits_per_pixel = 24;
img.red_mask = 0xff0000;
img.green_mask = 0xff00;
img.blue_mask = 0xff;
if (!XInitImage(&img))
{
return 1;
}
image_size = img.width * img.height;
img.data = malloc(3 * image_size);
if (img.data == NULL)
{
return 1;
}
for (i = 0; i < image_size; ++i)
{
const GifColorType * const color = &cmap->Colors[gif->SavedImages[0].RasterBits[i]];
img.data[i * 3] = color->Red;
img.data[i * 3 + 1] = color->Green;
img.data[i * 3 + 2] = color->Blue;
}
DGifCloseFile(gif);
display = XOpenDisplay(NULL);
if (display == NULL)
{
return 1;
}
attr.event_mask = KeyPressMask | ExposureMask;
window = XCreateWindow(display, DefaultRootWindow(display), 0, 0,
img.width, img.height, 0, CopyFromParent,
InputOutput, CopyFromParent, CWEventMask, &attr);
XMapWindow(display, window);
while (1)
{
XEvent event;
XNextEvent(display, &event);
switch (event.type)
{
case KeyPress:
return 0;
case Expose:
XPutImage(display, window, DefaultGC(display, DefaultScreen(display)),
&img, 0, 0, 0, 0, img.width, img.height);
break;
default:
break;
}
}
}
diff -uNrp giflib-4.1.6.orig/lib/dgif_lib.c giflib-4.1.6/lib/dgif_lib.c
--- giflib-4.1.6.orig/lib/dgif_lib.c 2011-07-22 10:47:51.000000000 +0000
+++ giflib-4.1.6/lib/dgif_lib.c 2011-07-22 12:48:03.099742104 +0000
@@ -1056,9 +1056,35 @@ DGifSlurp(GifFileType * GifFile) {
if (sp->RasterBits == NULL) {
return GIF_ERROR;
}
- if (DGifGetLine(GifFile, sp->RasterBits, ImageSize) ==
- GIF_ERROR)
- return (GIF_ERROR);
+ if (sp->ImageDesc.Interlace) {
+ const int w = sp->ImageDesc.Width, h = sp->ImageDesc.Height;
+ int i;
+
+ for (i = 0; i < h; i += 8) {
+ if (DGifGetLine(GifFile, sp->RasterBits + w * i, w) ==
+ GIF_ERROR)
+ return (GIF_ERROR);
+ }
+ for (i = 4; i < h; i += 8) {
+ if (DGifGetLine(GifFile, sp->RasterBits + w * i, w) ==
+ GIF_ERROR)
+ return (GIF_ERROR);
+ }
+ for (i = 2; i < h; i += 4) {
+ if (DGifGetLine(GifFile, sp->RasterBits + w * i, w) ==
+ GIF_ERROR)
+ return (GIF_ERROR);
+ }
+ for (i = 1; i < h; i += 2) {
+ if (DGifGetLine(GifFile, sp->RasterBits + w * i, w) ==
+ GIF_ERROR)
+ return (GIF_ERROR);
+ }
+ } else {
+ if (DGifGetLine(GifFile, sp->RasterBits, ImageSize) ==
+ GIF_ERROR)
+ return (GIF_ERROR);
+ }
if (temp_save.ExtensionBlocks) {
sp->ExtensionBlocks = temp_save.ExtensionBlocks;
sp->ExtensionBlockCount = temp_save.ExtensionBlockCount;
--- End Message ---
--- Begin Message ---
Version: 5.1.1-0.2
fixed in 5.1.1.
--- End Message ---
