Latest FFMPEG strange behavior under Ubuntu Hardy

[foobar789]

Hi,

I downloaded and compiled FFMPEG today from SVN. After some while I got it compiled and tried to load m4a file in Audacity (1.3.6). Crash! I got segmentation fault. Well I continued to fiddle with audacity - I loaded a WAV file and just for a whim of mind tried to load above mentioned m4a file and vóila! It loaded. So this is on my mind.

Does anyone have any clues how to get audacity to load m4a files right away without first loading some other file? I can provide "strace" logs if someone is interested.

[foobar789]

NEWS! EXTRA EXTRA!

I compiled latest audacity from CVS. Previous behavior persists.

[foobar789]

Phew...

So this is with latest CVS checkout: if I enable "debug" in "configure" (./configure --enable-debug) and create the binary, I can actually open AAC-file straight away without first having to open WAV file.

Any insights on this?

[foobar789]

More info of the current situation; when trying to open AAC-file enough times, it eventually succeeds. Usually I get AAC-file open on fourth or fifth try.

[steve]

It's not that I'm not interested, it's that I don't know the answer.
Good luck with getting it working, I'm watching this topic with interest (I'm another Ubuntu user).

[richardash1981]

Probably a bug in the AAC decoder within FFmpeg. Certainly, no reports other than from Ubuntu, suggesting that it's something up with Ubuntu's FFmpeg package rather than an audacity problem. If you can reproduce with a current FFmpeg SVN snapshot (say last month or so) then I'd be more interested because it might be a current issue with ffmpeg rather than a fixed one.

[foobar789]

True that. It is FFMpeg problem. I managed to override it with help of following:
http://www.gossamer-threads.com/lists/m ... vnz/346732

But in short, problem is with FFMpeg libavcodec/i386/dsputil_mmx.c
c->float_to_int16_interleave = float_to_int16_interleave_sse2;

for some peculiar or strange reason sse2 crashes almost every time, after i changed this line to:
c->float_to_int16_interleave = float_to_int16_interleave_sse;

it started to work like a charm. So now I can open AAC files straight from Audacity.

rgrds, Hermesetas