Package: release.debian.org
Severity: normal
User: release.debian@packages.debian.org
Usertags: unblock
Hello,
Iain Lane found a crash in the current v4l-utils which can
easily triggered by using certain webcams (#770340).
Upstream fixed the bug with a small patch which will be
included in 1.6.0-2.
Before uploading I'd like to have your pre-approval.
Thanks,
Gregor
unblock v4l-utils/1.6.0-2
-- System Information:
Debian Release: jessie/sid
APT prefers unstable
APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386
Kernel: Linux 3.11-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=C.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
diff -Nru v4l-utils-1.6.0/debian/changelog v4l-utils-1.6.0/debian/changelog
--- v4l-utils-1.6.0/debian/changelog 2014-10-05 20:48:12.0 +0200
+++ v4l-utils-1.6.0/debian/changelog 2014-11-20 19:45:23.0 +0100
@@ -1,3 +1,9 @@
+v4l-utils (1.6.0-2) unstable; urgency=medium
+
+ * Fix JPEG subsampling issue (Closes: #770340)
+
+ -- Gregor Jasny gja...@googlemail.com Thu, 20 Nov 2014 19:39:33 +0100
+
v4l-utils (1.6.0-1) unstable; urgency=medium
* Imported Upstream version 1.6.0
diff -Nru v4l-utils-1.6.0/debian/patches/fix-jpeg-subsampling.diff v4l-utils-1.6.0/debian/patches/fix-jpeg-subsampling.diff
--- v4l-utils-1.6.0/debian/patches/fix-jpeg-subsampling.diff 1970-01-01 01:00:00.0 +0100
+++ v4l-utils-1.6.0/debian/patches/fix-jpeg-subsampling.diff 2014-11-20 19:45:23.0 +0100
@@ -0,0 +1,83 @@
+Author: Hans de Goede hdego...@redhat.com
+Origin: upstream, http://git.linuxtv.org/cgit.cgi/v4l-utils.git/commit/?id=757d7910ddf43d9a9187dddae4f51a57fb723e8d
+Date: Thu Nov 20 13:03:35 2014 +0100
+Bug-Debian: http://bugs.debian.org/770340
+Description: v4lconvert: Fix decoding of jpeg data with no vertical sub-sampling
+
+Our YUV output is always 2x subsampled in both vertical and horizontal
+direction, but some cameras generate JPEG data which is only subsampled in
+the horizontal direction.
+
+Since averaging the extra UV data these JPEGs contains is somewhat slow,
+and UV data is not all that important anyways, we simple take every other
+line. Or at least that is the intent.
+
+But before this commit the code was not doing this properly, for each 16
+Y input lines 1 - 16 we also get 16 UV input lines 1 - 16, but we only need
+8 output lines. so we should store input line 1 or 2 in output line 1, input
+line 3 or 4 in output line 2, etc. Instead we were storing input lines
+9 - 16 into output lines 1 - 8, which leads to some unwanted color bleeding.
+
+More over this also leads for 1920x1080 JPEG to us writing (1080 / 8 + 1) / 2
+* 8 = 544 UV output lines rather then 540, this means that the last 4 U output
+lines overwrite the first 4 V output lines, and worse that the last 4 V output
+lines overrun the output buffer.
+
+So far this only lead to some wrong colors in various places, but since that
+we dynamically allocate the output buffer to just the right size this actually
+causes a crash.
+
+This commit fixes both the crash, and the wrong colors.
+
+Signed-off-by: Hans de Goede hdego...@redhat.com
+
+--- a/lib/libv4lconvert/jpeg.c
b/lib/libv4lconvert/jpeg.c
+@@ -242,23 +242,34 @@
+ y_rows[y] = ydest;
+ ydest += width;
+ }
+- for (y = 0; y 8; y++) {
+- u_rows[y] = udest;
+- v_rows[y] = vdest;
+- udest += width / 2;
+- vdest += width / 2;
++ /*
++ * For v_samp == 1 were going to get 1 set of uv values per
++ * line, but we need only 1 set per 2 lines since our output
++ * has v_samp == 2. We store every 2 sets in 1 line,
++ * effectively using the second set for each output line.
++ */
++ if (v_samp == 1) {
++ for (y = 0; y 8; y++) {
++u_rows[y] = udest;
++v_rows[y] = vdest;
++y++;
++u_rows[y] = udest;
++v_rows[y] = vdest;
++udest += width / 2;
++vdest += width / 2;
++ }
++ } else { /* v_samp == 2 */
++ for (y = 0; y 8; y++) {
++u_rows[y] = udest;
++v_rows[y] = vdest;
++udest += width / 2;
++vdest += width / 2;
++ }
+ }
++
+ y = jpeg_read_raw_data(cinfo, rows, 8 * v_samp);
+ if (y != 8 * v_samp)
+ return -1;
+-
+- /* For v_samp == 1 were going to get another set of uv values,
+- but we need only 1 set since our output has v_samp == 2, so
+- rewind u and vdest and overwrite the previous set. */
+- if (cinfo-output_scanline % 16) {
+- udest -= width * 8 / 2;
+- vdest -= width * 8 / 2;
+- }
+ }
+ return 0;
+ }
diff -Nru v4l-utils-1.6.0/debian/patches/series v4l-utils-1.6.0/debian/patches/series
--- v4l-utils-1.6.0/debian/patches/series 2014-10-05 20:47:46.0 +0200
+++ v4l-utils-1.6.0/debian/patches/series 2014-11-20 19:33:25.0 +0100
@@ -1,3 +1,4 @@
dont-gererate-treeview.diff
man-section.diff
man-ellipsis.diff
+fix-jpeg-subsampling.diff
