[Ffmpeg-devel] Crash with -vhook

[Matthijs Douze]

Hi

On a Linux box, I run

./ffmpeg_g -an -vcodec copy -i x.3gp -vhook vhook/null.so xo.3gp

and I get:

-------------> snip

FFmpeg version SVN-r7868, Copyright (c) 2000-2006 Fabrice Bellard, et al.
   configuration: 
--prefix=/scratch2/cornwall/douze/compil/ffmpeg/installed --enable-shared
   libavutil version: 49.3.0
   libavcodec version: 51.32.0
   libavformat version: 51.8.0
   built on Feb  7 2007 12:50:11, gcc: 3.4.1 (Mandrakelinux 10.1 3.4.1-4mdk)

Seems stream 0 codec frame rate differs from container frame rate: 29.97 
(30000/1001) -> 25.00 (25/1)
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'x.3gp':
   Duration: 00:00:00.8, start: 0.000000, bitrate: 371 kb/s
   Stream #0.0(und): Video: h263, yuv420p, 176x144, 25.00 fps(r)
Called with argc=1
Output #0, 3gp, to 'xo.3gp':
   Stream #0.0: Video: h263, yuv420p, 176x144, q=2-31, 25.00 fps(c)
Stream mapping:
   Stream #0.0 -> #0.0
Press [q] to stop encoding
Segmentation fault (core dumped)

<--------------------- snap

The file x.3gp is available here:

http://lear.inrialpes.fr/~douze/ffmpeg_bug/x.3gp

The bug appears also with an avi file or on a x64 box with gcc 4.1.1. It 
does not appear if there is no vhook.

In gdb:

-----------------------> snip
(gdb) bt
#0  0x4050f03c in memcpy () from /lib/tls/libc.so.6
#1  0x401a613a in ff_img_copy_plane (dst=0x400149e8 "\230I\001@", 
dst_wrap=0,
     src=0x1 <Address 0x1 out of bounds>, src_wrap=1075471116, 
width=135246136,
     height=88) at imgconvert.c:737
#2  0x401a630c in img_copy (dst=0x0, src=0x48, pix_fmt=88, width=1077415168,
     height=1) at imgconvert.c:786
#3  0x0804b807 in pre_process_video_frame (ist=0x0, picture=0x3baa0c40,
     bufp=0xbfffeb60) at ffmpeg.c:613
#4  0x0804d7fe in output_packet (ist=0x0, ist_index=-1073744796,
     ost_table=0xbffff3f0, nb_ostreams=134547985, pkt=0x80802e0)
     at ffmpeg.c:1145
#5  0x08050a11 in av_encode (output_files=0x1, nb_output_files=0,
     input_files=0x1, nb_input_files=0, stream_maps=0x0,
     nb_stream_maps=1079775768) at ffmpeg.c:1937
#6  0x080553e3 in main (argc=9, argv=0xbffff464) at ffmpeg.c:3932

<----------------------- snap

Any idea ?

Thanks

Matthijs