[Ffmpeg-devel] [BUG] Interlaced DCT Compare Crashing

[Michael Niedermayer]

Hi

On Mon, Nov 20, 2006 at 08:32:12PM -0600, Brian Brice wrote:
> Hello.
> 
> I am testing alternative interlaced DCT compare functions and I seem to
> be running into problems.  This is the command line I am using:
> 
> ./ffmpeg-nt -i ShortDV.avi -f vob -vcodec mpeg2video -b 7M -minrate 7M
> -maxrate 7M -bufsize 224KiB -g 12 -bf 2 -s ntsc -r ntsc -acodec mp2 -ab
> 128K -ar 48000 -flags ildct -v 0 -ildctcmp sad -y out.mpg
> 
> Setting ildctcmp to {sad,sse,rd,dct,nsse,dctmax,chroma} seems to cause a
> crash within ffmpeg.  I've narrowed it down to the point it crashes, and
> it seems to be due to dereferencing a NULL pointer.  Based on current
> SVN, this occurs in libavcodec/mpegvideo.c, line 4387.  From what I can
> tell, these types of ildctcmp functions do not fill in the 5th element
> of their cmp_func array in dsputils.  Is adding the
> CODEC_FLAG_INTERLACED_DCT not suppose to be used with these compare
> functions?

ildctcmp only works with VSAD and VSSE feel free to add more comparission
functions or write some sort of generic wraper for the others ...
or add a check which prints an error message instead of crashing
all are welcome as patches ...

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

In the past you could go to a library and read, borrow or copy any book
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