[Ffmpeg-devel] bug report: ffmpeg converting error - AVI to MP4

[Kostya]

On Sun, Feb 18, 2007 at 11:06:20AM -0800, Jimmy wrote:
> Hello.
> 
> I am trying convert from AVI to MP4.
> The codecs I use for AVI are:
>     - video: PicVideo M-JPEG
>     - audio: PCM 44.1kHz, 16 bit, stereo
> 
> The convertion process goes smoothly for a while and at a point ffmpeg starts returning alot of errors.
> The most common is "[mjpeg @ 0x840fbc0]Subsampling in JPEG-LS is not supported."
> >From the time the error occurs the resulted MP4 has white image frames.
> I am recording with iuVCR v. 4.7.4.293.

This codec violates JFIF format.

Those pictures which are almost correct are missing huffman table 0x00
(ancient FFmpeg build 4747 handles them correctly, new FFmpeg and
libjpeg-based programs could not handle them at all).

Those frames which give you errors consist of
sequences FF <random byte> 00 <another random byte>.

BTW can you play it with original codec?
 
> The command line: ffmpeg -i JPEG-LS_error.avi -r 25 JPEG-LS_error.mp4
> 
> I uploaded also the AVI file that generates these errors: upload.mplayerhq.hu/MPlayer/incoming/mjpeg/JPEG-LS_error.avi
> 
> Thank you so much.
> Jimmy