[FFmpeg-user] zimg colorspace yuv -> rgb possible?

[Andy Furniss]

Paul B Mahol wrote:
> On 1/27/16, Andy Furniss <adf.lists at gmail.com> wrote:
>> Carl Eugen Hoyos wrote:
>>> Andy Furniss <adf.lists <at> gmail.com> writes:
>>>
>>>> mplayer -ss 11.2 -frames 3 -demuxer lavf -noaspect -vf
>>>> ilpack,scale -vo png ~/snooker-short.ts
>>>
>>> First convert the input file losslessly to something I-frame only
>>> (like ffv1), then testing will get (much) easier.
>>
>> Yea was in progress, finished now (used y4m).
>>
>> So this is the test frame snk-420i.y4m
>>
>> https://drive.google.com/file/d/0BxP5-S1t9VEENjJpRk5vV0FjSFU/view?usp=sharing
>>
>>
>>
This is what results look like -
>>
>> https://drive.google.com/file/d/0BxP5-S1t9VEEaEVUTzJQc1dseWc/view?usp=sharing
>>
>
>>
> Isnt your input already 422?

No, that one was a different test I made for zscale so I could compare
with swscale both progressive. Result zscale is better that swscale no
flags but the same if I use flags

-sws_flags +accurate_rnd+full_chroma_int

> I guess you could use ffmpeg and scale filter to convert from yuv420
> to yuv422p with interl=1 and than use zscale to convert yuv422p to
> gbrp and than again scale to convert from gbrp to rgb24 for png:
>
> ffmpeg -i input -vf
> scale=interl=1,format=yuv422p,zscale=range=limiter:min=709,format=gbrp
>  out.png


That's sort of what I did (in more stages) it seems that although going
to 422 interl=1 first is better it still isn't as good as using ilpack.