Enable AMV encoding for audio

[shimmy]

The  amv format is made for chinese s1mp3 hardware players, and is now part of the latest version of FFmpeg (0.9 - Harmony).

However, its underlying audio is adpcm_ima_amv, and this is unsupported by FFmpeg.

When I call ffmpeg -codecs, it contains the line D A D adpcm_ima_amv ADPCM IMA AMV, which means Decoding supported, Audio codec, Direct rendering, but it doesn't contain E which stands for Encoding.

I found the  amv-codec-tools project, which supports this audio format automatically.

I think it would be easy to merge the outdated adpcm_ima_amv encoder from the amv-codec-tools into FFmpeg.

To be noted, compiling amv-codec-tools with the new FFmpeg version doesn't work, even I disable the amv and the adpcm_ima_amv encoders/decoders, I get this error:

[NULL @ 039a7860] Requested output format 'amv' is not a suitable output format
sample.amv: Invalid argument

Which is the same error that occurs when trying to use FFmpeg 0.9 for the AMV format - an issue that should be reported separately.

This issue is very urgent to me and I consider promoting a developer that will make it work.

[cehoyos]

 http://code.google.com/p/amv-codec-tools/source/list?path=/trunk/AMVmuxer/ffmpeg/libavcodec/adpcm.c

[shimmy]

Replying to cehoyos:

 http://code.google.com/p/amv-codec-tools/source/list?path=/trunk/AMVmuxer/ffmpeg/libavcodec/adpcm.c

The correct link to the file should be:  adpcm.c

Here are links to the adpcm code-files in FFmpeg:
 adpcmenc.c adpcm.c adpcm.h adpcm_data.c adpcm_data.h

---

 More documentation on the AMV format
 Source code for an AMV decoder written in Perl

Anyone who has plans on implementing this any time soon, please contact me asap. This is very essential to me.
Thank a lot!