Years ago I tried to do a tutorial on the Hald CLUTs: https://www.cinelerra-gg.org/forum/how-to/color-matching-scene-to-scene/ However, with ffmpeg you don't get quality LUTs and they can cause clipping or other glitches. This link may also be of interest: https://www.cinelerra-gg.org/forum/help-video/francebb-luts-for-space-color-conversions/