[FFmpeg-devel] [PATCH] lavf/avienc: Store palette at keyframes

Mats Peterson matsp888 at yahoo.com
Sun Mar 6 00:04:18 CET 2016

Mats Peterson <matsp888-at-yahoo.com at ffmpeg.org> skrev: (5 mars 2016 23:31:40 CET)
>On 03/05/2016 11:23 PM, Mats Peterson wrote:
>> On 03/05/2016 11:20 PM, Mats Peterson wrote:
>>> On 03/05/2016 11:00 PM, Mats Peterson wrote:
>>>> Here is an experimental and much simpler solution that stores the
>>>> used palette at keyframes regardless. Maybe too simple, Michael, I
>>>> know.
>>> This simplicity leads to storing an xxpc chunk with the same palette
>>> every keyframe when there is only one palette in the original file.
>>> Perhaps not acceptable.
>> It's at least better than storing an xxpc chunk for every frame.
>> Mats
>Ouch. Every packet in toon.avi contains a keyframe...
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>ffmpeg-devel at ffmpeg.org

This thing about storing xxpc palette switching chunks at every keyframe is rather much overkill, and more of academic interest than anything else in my book. Take that toon.avi file for example, every frame in it is a keyframe, yet it only contains two xxpc chunks. And Reimar, you would be hard pressed to find a 2gb 8 bpp file with xxpc chunks. This only concerns older and relatively short clips really. But if you want to implement something on top of what's already done, Michael, by all means, go ahead. Just as long as it will work with both stream copy, raw and non-raw video.

Mats Peterson

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