Is H.264 lossless really lossless?
 

I need to put some DVD clips into Final Cut Pro X, and was wondering if I use Handbrake to VidCoder @ RF 0 if the resulting H.264 stream is actually a lossless conversion. Since it is going from 4:2:0 MPEG-2 to 4:2:0 H.264, I'm thinking there shouldn't be too much going on in the colorspace that would cause massive shifts or result in color quality loss. Detail wise, comparing frames to frames, is it truly lossless?

I don't think there's anything lossless about H.264/AVC/MPEG-4. It's a lossy codec intended for high compression, period. H.265/HVEC is building on it.

I've only read theory papers in years past about it being potentially lossless, but have not actually seen anything tangible. In several cases, it's bastardizing the term "lossless" to mean "lossy but not (easily) perceivable". Or weasel terms like "visually lossless".

Not the same. :smack:

Data in = data out.

Was this ffmpeg?

If you click the top-right corner showing the thread title in the link, it takes you to the full thread where the question was about x264. But given that ffmpeg uses x264 anyway I'm not sure what you're asking.