Function unsharp 

pub fn unsharp(sizes: [u32; 4]) -> String

ffmpeg’s unsharp with luma lx x ly and chroma cx x cy matrices (sizes), the binomial blur ffmpeg’s repeated [1 2 1] passes give, amounts luma and chroma as params: luma on BT.601 Y (the same delta on R, G and B), chroma on the rest of the pixel.