[FFmpeg-devel] [PATCH] avformat/avienc: Store pal8 palette

Mats Peterson matsp888 at yahoo.com
Fri Feb 19 14:22:44 CET 2016


On 02/19/2016 02:15 PM, Mats Peterson wrote:
> On 02/19/2016 02:08 PM, Mats Peterson wrote:
>> On 02/19/2016 02:05 PM, Mats Peterson wrote:
>>> On 02/18/2016 11:07 PM, Mats Peterson wrote:
>>>> On 02/18/2016 11:04 PM, Michael Niedermayer wrote:
>>>>> On Thu, Feb 18, 2016 at 10:40:42PM +0100, Mats Peterson wrote:
>>>>>> On 02/18/2016 10:27 PM, Mats Peterson wrote:
>>>>>>> On 02/18/2016 09:14 PM, Michael Niedermayer wrote:
>>>>>>>> This can be made more efficient, but first and the main goal of
>>>>>>>> this
>>>>>>>> change is to
>>>>>>>> store it at all
>>>>>>> Great, Michael. I'll try it out.
>>>>>>>
>>>>>>> Mats
>>>>>>>
>>>>>>
>>>>>> I notice that the palette inclusion is only made by using 'xxpc'
>>>>>> chunks in the video data so far. I'm not so sure if these in-data
>>>>>> palette changing chunks are widely supported. Therefore, first and
>>>>>> foremost, and the most widely supported way in my book, is to add an
>>>>>> "initial" palette after the BITMAPINFOHEADER in the strf chunk.
>>>>>> That's where I found it to be a bit tricky, but I'm sure you can
>>>>>> solve it in some way.
>>>>>
>>>>> its quite easy to implement if you want to try
>>>>> just leave some space where the palette should go whe writing the
>>>>> headers and keep track of the location, then when the first
>>>>> packet comes in take its palette and store it there
>>>>>
>>>>
>>>> I could try, yes. But not tonight, I'm a bit tired :) I'll look into
>>>> it,
>>>> perhaps I can make it.
>>>>
>>>> Mats
>>>
>>>
>>> Will you apply your latest xxpc writing patches to the repository,
>>> Michael? I noticed you haven't done it yet.
>>>
>>> Mats
>>
>> The stuff with CONTAINS_PAL etc.
>>
>
> I forgot that I had added them before starting to work on this. It would
> be nice if you could apply them "officially" before I continue, since
> they work well.
>
> Mats
>

Fairly well, that is. The palette is incorrectly written to the file in 
big endian RGB order, but it should be in little endian BGR order. But 
I'll fix that myself.

Mats



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