[Ffmpeg-devel] Re: Problems Decoding DivX

[Michael Niedermayer]

Hi

On Sun, Sep 04, 2005 at 06:23:22PM +0200, Diego Biurrun wrote:
> On Sun, Sep 04, 2005 at 05:17:19PM +0200, matthieu castet wrote:
> > Diego Biurrun wrote:
> > 
> > >>>upload debugger output from ffmpeg_g and upload the theora file too if it
> > >>>fails on linux too
> > >>
> > >> I can't check this on Linux as I won't have access to a Linux box until
> > >>Monday.  But I will try to do it then.  In the meantime I have uploaded 
> > >>the
> > >>first MB or so of the crashing file to my website.  It can be found at:
> > >>
> > >> http://www.codehq.org/Sahara.ogg
> > >
> > >
> > >Works with MPlayer and libtheora, ffplay crashes as does MPlayer with
> > >the libavformat demuxer.
> > >
> > Works fine on IA32, but IIRC when I tried to play some ogg file on PPC, 
> > I catch somehing strange with bitstream reader, endian conversion or 
> > something like that.
> > 
> > Have you got the gdb backtrace ?
> 
> Is this enough?

no, missing disassembly, register values, gcc version, and try to compile 
vp3.c with -O0

[...]
> Program received signal SIGSEGV, Segmentation fault.
> [Switching to Thread 823940320 (LWP 13478)]
> 0x1006a8b8 in get_bits_long (s=0x311c4990, n=32) at bitstream.h:607
> 607         tmp= SHOW_UBITS(re, s, n);

SHOW_UBITS just shifts a local variable right, not sure how that can
segfault, but maybe iam too tired and miss something ...

[...]
-- 
Michael