[FFmpeg-devel] [PATCH 1/2] lavf/avienc: Simplify palette handling

[Mats Peterson]

On 02/27/2016 09:21 PM, Mats Peterson wrote:
> On 02/27/2016 08:42 PM, Reimar Döffinger wrote:
>> On Sat, Feb 27, 2016 at 07:51:41PM +0100, Michael Niedermayer wrote:
>>> should rawvideo AVPackets palette use data[] or sidedata, honestly i
>>> do not know, but i dont think it makes a big difference
>>> even supporting both, likely only adds 3-5 lines of code or so
>>> its more a philosophical question
>>
>> Not sure how much was in response to my complaints, but
>> if this parts was I think that misses my point, as I
>> agree that it doesn't matter which.
>> What matters though is:
>> The AVI demuxer creates AVPackets with palette in side data,
>> and the AVI muxer supports ONLY palette appended in the data.
>> How to fix it might be philosophical, but I think it's not
>> philosophical and fairly clear that that's just broken.
>> Even remuxing from AVI to AVI simply won't work without a
>> "decoder" (which is not an issue performance-wise, but it
>> is usability wise, how should a FFmpeg user know that for
>> paletted video and only that a lossless stream copy requires
>> "decoding" and "encoding"?).
>>
>>> about existing API, i suspect there arent many applications that
>>> use ffmpegs demuxers without the decoders  for raw pal8, i might
>>> of course be wrong but this seems a rather uncommon case of a uncommon
>>> case. And muxers side it was all broken before mats ...
>>
>> Well, then we know I can only blame Mats for "only" making it
>> better instead of perfect :)
>> _______________________________________________
>
> Well, before my patches, there was no palette inclusion whatsoever in
> AVI or QuickTime on muxing. Anyway, you're right about the stream
> copying not working. Just tried it here. Another issue to take care
> of... phew.
>

Solving the stream copying issues obviously requires using side data 
packets in the muxers, correct me if I'm wrong.

Mats