FWIW when I asked about doing something on IRC (splitting a stream, process one, and overlay it over the existing one at 20%), they were quite helpful. It was:

FWIW when I asked about doing something on IRC (splitting a stream, process one, and overlay it over the existing one at 20%), they were quite helpful. It was: `split[a][b];[b]lut3d=${path}[c];[a][c]blend=all_mode=overlay:all_opacity=${opacity}`