[FFmpeg-user] Trying to get lossless PNG -> VP9 (yuv) -> PNG

[Carl Eugen Hoyos]

2018-08-01 6:12 GMT+02:00, Kirk Liberty <kirk.liberty at gmail.com>:
> On Tue, Jul 31, 2018 at 7:04 PM, Carl Eugen Hoyos <ceffmpeg at gmail.com>
> wrote:
>>
>> 2018-07-29 0:16 GMT+02:00, Kirk Liberty <kirk.liberty at gmail.com>:
>> > My plan is to use the YCgCo
>> > colorspace to get lossless conversion of rgb->yuv->rgb
>>
>> This conversion (may be lossless in theory but) is not lossless
>> with FFmpeg, both x264 and libvpx-vp9 support encoding rgb
>> which can be lossless.
>
> Why is YCgCo not lossless in FFmpeg?

It is / can be.
What is not lossless is the conversion from PIX_FMT_GBR* (or RGB*)
to PIX_FMT_YUV*

Carl Eugen