-grayscale fails on CMYK JPEGs
Dinesh said, on 28/05/2023
https://i.imgur.com/GYiqgHK.jpg
pingo -grayscale -sb GYiqgHK.jpg
pingo simply prints `no savings` when attempting to grayscale a CMYK JPEG. Is lossless discarding of chroma channels possible on CMYK images?
cédric (dev) said, on 23/06/2023
pingo can not do this losslessly — it could do lossy CMYK to grayscale if image has color profile