>you would notice I don't think this is a good metric. For fun and entertainment, it works, but lots of contexts need more than that. Take an example of lossy

>you would notice I don't think this is a good metric. For fun and entertainment, it works, but lots of contexts need more than that. Take an example of lossy audio, like MP3. People are generally fine with 128k mp3s, but I doubt audio engineers would want to store masters in that format and bitrate. In case of colorization, the issue is that the color really is lost on the film. Multiple shades of different colors map to the same shade of grey on black and white media - my favorite example is that B&W TV make-up was bright green. So them no matter what you do, it'll be just a conjecture of what the original color might have been.