That's not lower resolution, that's lower precision. It's the difference between...

hxa7241 · on Nov 24, 2009

I understand the difference, which is why I said 'lower resolution, spatially and dynamically'.

Are you saying definitively that chrominance is not encoded at lower spatial resolution?

I also said it might be another cause of difference, not the cause.

Anyone might want to look at http://en.wikipedia.org/wiki/4:2:2 before simply assuming I am talking nonsense.