[FFmpeg-devel] [PATCH] lavc/rawdec: Only use AV_PIX_FMT_PAL8 for 1 bpp video

[Mats Peterson]

On 02/01/2016 04:48 AM, Mats Peterson wrote:
> On 01/31/2016 11:22 PM, Mats Peterson wrote:
>
>>> also i dont think its just avi. The raw video decoder is potentially
>>> used for more than avi.
>>> mkv and nut come to mind as potential formats that might use the
>>> same codepath
>>>
>>
>> Yes it is used for other file formats as well, but only AVI and
>> QuickTime explicitly have a palettized 1 bpp mode (as far as I know), so
>> they should use pal8 for 1 bpp, and not monow. Other formats aren't
>> affected.
>>
>> Mats
>
>
> Your patch that switches to monow when a 1 bpp AVI doesn't contain a
> palette is rather kludgy and redundant to me. And users will undoubtly
> be more surprised when they discover that monow is used for the special
> case of 1 bpp AVI without a palette, rather than using pal8 consistently
> for all 1 bpp AVI files, just like 2 and 4 bpp.
>
> I don't understand what's so important about retaining monow inside
> FFmpeg when it comes to AVI, when it's obviously OK to convert 2 and 4
> bpp to pal8. Once again, if you want a straight passthrough of 1 bpp AVI
> video data, just use "-c:v copy".
>
> Mats
>
-
It is also semantically wrong to use monow for 1 bpp AVI, since there is 
no such thing as "monochrome AVIs".

Mats