Cant believe this blasfemy, LOL
Is there a sense of mac troll in the air... LOL again
H.264 decoder encoder as always been bad (not universal) implemented in QuickTime, in macs.
To the point you need to install a different media player to decode a proper encoded video. I mean outdated, incapable of decoding high bitrates and so on.
and don't encode quicktime H264 files from premiere or AME, is also very outdated, use the dafault H264 codec that is years ahead.
As far as I Know, that haven't changed much, or maybe it did.
If you look closely the FCPX image is a little darker, that makes the error more obvious and the quicktime decoder error no mistake.
Looks like quicktime gamma bug, or any other bug.
Just as exercise try to take the same snapshots from a media player not using quicktime decoder. Try This : http://mplayerx.org/
And from AME using default H264 not quicktime one, using exactly the same specification thick the two boxes "render at maximum depth" and "use maximum render quality", and at the end select at the multiplexer tab under the stream compatibility option IPOD.
than post again, this is a clear MAC FCPX infomercial.
Also posted in other foruns
GH4 is UHD 4:2:2 10bits out from the hdmi :-)