[Ffmpeg-devel] [PATCH]add codec id for TTA and WavPack in riff.c

[Benjamin Larsson]

David Bryant skrev:
> Hi,
>
> yong wrote:
>> Hi, with this pacth applied,
>> trasncoding tta/wavpack to other audio codec in ffmpeg  will work,
>> playback in ffplay will work too. :)
>>
>> Index: libavformat/riff.c
>> ===================================================================
>> --- libavformat/riff.c    (revision 6533)
>> +++ libavformat/riff.c    (working copy)
>> @@ -191,6 +192,8 @@
>>      { CODEC_ID_ADPCM_CT, 0x200 },
>>      { CODEC_ID_ADPCM_SWF, ('S'<<8)+'F' },
>>      { CODEC_ID_TRUESPEECH, 0x22 },
>> +    { CODEC_ID_TTA, MKTAG('T', 'T', 'A', '1') },
>> +    { CODEC_ID_WAVPACK, MKTAG('W', 'V', 'P', 'K') },
>>  
>>      // for NuppelVideo (nuv.c)
>>      { CODEC_ID_PCM_S16LE, MKTAG('R', 'A', 'W', 'A') },
>>
>>
>>   
> I am the developer of WavPack, but I'm very new to ffmpeg and I don't 
> really understand what this does. It is in a list of format ids for 
> the wav container but WavPack in wav is not supported. Also, in the 
> wav header those ids are only 16-bit so WVPK can't fit. I assume that 
> this table means something else in the ffmpeg context, but I could not 
> figure out what (especially since I did not see FLAC in there and I 
> know that's supported).

I think your point is valid and that the patch author mixed the riff 
id's with fourcc's.

>
> I haven't made it through all the docs yet (or built the code) but any 
> light shed on this would be appreciated. As was mentioned, the 
> signature for WavPack blocks is "wvpk", so that would be a fine choice 
> by me for this (assuming it's not really a wav format_id).
>
> I also very much appreciate the work done to add WavPack support to 
> ffmpeg. Once I get a feel for everything (and get version 4.4 
> released) I may be able to contribute to WavPack support also.
>
> Thanks,
> David


MvH
Benjamin Larsson