How to change Y/C delay in ffmpeg?

[aramkolt]

Hello all, wondering if anyone knows the proper way to apply a "YC delay" within ffmpeg?

This would be shifting the color to the right or left of luma by a fixed number of pixels (or usually more often described in milliseconds of time that it'd take to draw the line) and may use a different term within ffmpeg which might be why I'm not seeing much about it when I Google. "YC delay" is more the term I'm used to since it is present on a variety of TBCs and is really useful during capture, though it is sometimes hard to tell in realtime what the ideal YC delay value is on a preview monitor and it would be good to know how to adjust that post-capture.

I also believe that it would beneficial to adjust the YC delay before actually deinterlacing?

Attached is my sample clip. You can kind of see how Bob(Dylan)'s blue jean jacket color is shifted to the right of his shirt and there's seemingly absent color to the very left of the jacket by the same "width".

As far as capture went, this was a U-Matic capture of his only SNL performance in 1979 and is likely a lower generation dub of the edited master and then I captured it via SDI with an AJA KiPro to ProRes422HQ. I like ProRes for the 10 bit color and Mac friendliness.

[jagabo]

chromashift:
https://ayosec.github.io/ffmpeg-filters-docs/7.1/Filters/Video/chromashift.html

[pandy]

As it looks chromashift filter allow only pixel accuracy - if you need higher accuracy (subpixel precision) you can separate planes, resize Cb/Cr (horizontally) and shift as much you wish - this will give you possibility to shift with subpixel accuracy (for example possibility to shift with accuracy of 1/4 pixel if you rescale plane 4 times, 1/8 pixel need 8 times enlarged, higher upscaling factor provide higher subpixel accuracy).
After shift you need to rescale it back to original size and combine with Y plane