[FFmpeg-trac] #10092(avcodec:new): DivX 5.0 interlaced b-frames video decodes with artifacts

[FFmpeg]

#10092: DivX 5.0 interlaced b-frames video decodes with artifacts
-------------------------------------+-------------------------------------
             Reporter:  Timofey      |                    Owner:  (none)
  Vasenin                            |
                 Type:  defect       |                   Status:  new
             Priority:  normal       |                Component:  avcodec
              Version:  git-master   |               Resolution:
             Keywords:               |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
Description changed by Timofey Vasenin:

Old description:

> Summary of the bug:
> FFMPEG decodes DivX 5.0 interlaced video with awful block artifacts.
>
> I assume DivX generates buggy bitstream (as XviD also decodes with
> artifacts), but at least it is decoded correctly by DivX itself.
>
> How to reproduce:
> {{{
> - Encode any video as interlaced using DivX codec (tested with DivX Pro
> 5.0.5 + VirtualDub2 44828) with b-frames enabled (this is default for
> DivX Pro 5.0.5 encoder) and all other settings left as default.
> - Try to decode the result with ffmpeg:
> ffplay divx_interlaced_decoding_artifacts.avi
> - The resulting video has lot of visible block artifacts, mostly
> noticeable on b-frames.
> }}}

New description:

 Summary of the bug:
 FFMPEG decodes DivX 5.0 interlaced b-frames video with awful block
 artifacts.

 I assume DivX generates buggy bitstream (as XviD also decodes with
 artifacts), but at least it is decoded correctly by DivX itself.

 How to reproduce:
 {{{
 - Encode any video as interlaced using DivX codec (tested with DivX Pro
 5.0.5 + VirtualDub2 44828) with b-frames enabled (this is default for DivX
 Pro 5.0.5 encoder) and all other settings left as default.
 - Try to decode the result with ffmpeg:
 ffplay divx_interlaced_decoding_artifacts.avi
 - The resulting video has lot of visible block artifacts, mostly
 noticeable on b-frames.
 }}}

--
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/10092#comment:2>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker