Hello.
Is the quicktime photoJPEG compression (at 100%quality) 4:2:2 or 4:2:0?

thanks!

Neither, at 100% it's RGB 4:4:4

At 75% it's Y'CbCr 4:2:2

Graeme

Thanks!
Then, if at 100% it s 4.4.4 where does the compression came from? becasuse file sizes are considerably much smaller than uncompressed images.

And why is that when i render the same file from after effects, instead of vegas (with same settings), the file size is more than twice?

About Vegas / AE, I have no idea.

The compression comes from quantising the discrete cosine transform coeficients - that's how JPEG works, and how it gives variable compression amounts. PhotoJPEG is a superb codec for high quality and small (relatively) sizes.

Graeme