DE you gonna share this filter?

Maybe, but it's not doing anything that AviSynth's coloryuv doesn't do. I just like to work in RGB32, so I wrote a filter that takes 32-bit RGBA and turns it into 12-bit Y+10 bit U+10 bit V, then another that can do the coloryuv stuff on that, then another that transforms it back to RGB32 (sounds horrendous but it's lossless if you do no operations, so I think I'm okay). In theory this gives 16x the luma resolution than converting to YUV and operating on that.

The previous filter, cyanide, which I'm still going to use as well, is pretty much just a subset of what my experimental selectivecolour filter can do.