kitsu
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cgwire
Kitsu not maintaining uploaded QT's colour space for Revisions
Kitsu is not maintaining the same Colour space for previews. Uploading a sample in Rec2020 ST 2084 converts to Rec709 with a major colour shift.
Steps to reproduce: Upload aforementioned Rec2020 ST2084 sample as Revision, resulting generated QT is converted to Rec709 with colour shift.
Expected output: same colour space, just converted to h.264 for preview purposes
Hello @PeteDraper, do you know if it's something possible with FFMPEG? We didn't dig into colorspaces yet with it.
yes I believe so. FFMPEG can do wondrous things. basically, you just don't want to change the colour space of the source
Ok we will see what we can do about it. If you can provide a test video, that would help.
You can shoot anything with your iPhone on cinematic mode which outputs a Rec2020 (HLG2100) and upload that. The resulting Revision file doesn't tone map nicely and converts to a rec709. Would expect it to convert to a h.264 / h.265 but maintain the same colour space as the source material.
As discussed on discord, here's a deepdive on ffmpeg and colorspaces from the canva blog.
https://www.canva.dev/blog/engineering/a-journey-through-colour-space-with-ffmpeg/
Some additional links from the ASWF Media Review working-group, they try to establish good encoding practices for VFX review:
- https://richardssam.github.io/ffmpeg-tests/
- https://wiki.aswf.io/pages/viewpage.action?pageId=16031068
