[Ffmpeg-devel] Re: ffmpeg & lame low bitrate causes failed assertion

[Benoit Fouet]

Hi,

Asli Binal wrote:
> Benoit Fouet <benoit.fouet <at> purplelabs.com> writes:
>
> *snip!*
>
> Ben,
> I appreciate your help, I think the reason you weren't able to reproduce the
> issue is due to the sample file that was ftp'd - I'm going to upload the sample
> file that always fails with senduit -  if you can grab the shortinput.wav file
> from there - you might be able to reproduce the issue.  However, since you're
> using an older version of lame, there's a chance that you might not be able to
> replicate the issue.
>   
it seems so, i cannot reproduce the problem with my config here...
FFmpeg version SVN-r8090
LAME 3.97 32bits

(Note: my version of lame is unable to encode properly this file:
$ lame -b 32 --resample 44.1 shortinput.wav output.mp3
Assuming raw pcm input file
which is wrong, as it is not raw pcm input file)

> Here's the location of the file, shortinput.wav is 28.2MB: http://senduit.com/6935aa
>
> Again, the command I ran with:
> ffmpeg -i shortinput.wav -vn -ab 32 output.mp3 
>
> and the output:
>
> FFmpeg version SVN-r8045, Copyright (c) 2000-2007 Fabrice Bellard, et al.
>   configuration: --prefix=/Users/Asli/CODE/ffmpeg/installed --enable-libmp3lame
> --enable-gpl --extra-cflags=-I /Users/Asli/CODE/lame/installed/include
> --extra-ldflags=-L/Users/Asli/CODE/lame/installed/lib
>   libavutil version: 49.3.0
>   libavcodec version: 51.34.0
>   libavformat version: 51.10.0
>   built on Feb 20 2007 15:28:37, gcc: 4.0.1 (Apple Computer, Inc. build 5367)
> Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/Users/Asli/Desktop/shortinput.wav':
>   Duration: 00:02:47.7, start: 0.000000, bitrate: 1411 kb/s
>   Stream #0.0(eng): Audio: pcm_s16be, 44100 Hz, stereo, 1411 kb/s
> Output #0, mp3, to 'output.mp3':
>   Stream #0.0: Audio: mp3, 44100 Hz, stereo, 32 kb/s
> Stream mapping:
>   Stream #0.0 -> #0.0
> Press [q] to stop encoding
> quantize.c:2050: failed assertion `cod_info->part2_3_length <= MAX_BITS'
> Abort trap
>
> (the output.mp3 plays back fine, but it's only 00:02:32.63 in duration with a
> file size of "610,534 bytes")
>
>   
i think i cannot help you further...

Ben