[FFmpeg-devel] [PATCH] lavc/rawdec: Remove monowhite switching code for 1 bpp AVI without a palette

[Mats Peterson]

On 02/06/2016 05:17 AM, Mats Peterson wrote:
> On 02/06/2016 05:05 AM, Mats Peterson wrote:
>> This patch removes the monowhite switching code for 1 bpp raw AVI
>> without a palette. I don't see any reason to keep it, since it's
>> semantically incorrect to use monowhite for palettized data in my book,
>> it adds unnecessary noise to the code, and it's inconsistent with the
>> rest of the code in FFmpeg.
>>
>> Regarding not being able to produce a working nut file with "ffmpeg -i
>> in.avi -vcodec rawvideo out.nut", it's no more of a regression than not
>> being able to produce a working nut file with the same command line from
>> a 2, 4 or 8 bpp file, since nut currently doesn't have a pal8 mode.
>>
>> In order to produce a working nut file from a 1, 2, 4 or 8 bpp AVI or
>> QuickTime file, force the pixel format with "-pix_fmt rgb24" or similar.
>> For black & white files in order to save space, use "-pix_fmt monow" or
>> "-pix_fmt monob".
>>
>> I have also updated the 1 bpp FATE test files (once again).
>>
>> Mats
>>
>
> And I deliberately kept the pal8 placeholders for the future in case you
> wonder, Michael.
>
> Mats
>

Yet another argument for removing this code is that AVI (and BMP 
indirectly) doesn't have a dedicated grayscale mode like PNG, or 
explicit black & white mode like TIFF's bilevel mode. Hence it should 
not use monowhite under any circumstances in my book.

Mats