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Another fun thing with processing that most people don't realize: almost all TVs will internally convert the input signal to YCbCr 4:2:2 for all this processing. Even though data is practically always transmitted as 4:4:4 over HDMI, and has to be converted back to RGB 4:4:4 to be displayed on the panel.

So if you have red/blue text (or anything with red/blue detail) looking awful, like it was lower resolution than it is, you have the TV to thank for that.

EDIT: to clarify, this doesn't apply if the text is a part of a movie (then you blame the codec for that, not the TV)




None of the broadcasts are 4:4:4, nor are the DVDs.

Hell, some of those HD broadcasts are 4:2:0 in order to reduce bandwidth.


Some? Practically every encoded video intended for end-users is 4:2:0 (and certainly everything in HDTV, Blu-ray, and DVD.)

I meant mainly for consoles, computers, and subtitles (though for subtitles it also depends on your DVD player) so I amended my post.


> and certainly everything in HDTV, Blu-ray, and DVD.

The HD broadcasts are 4:2:2, more often than not. There are a few stations that have their video servers down at 4:2:0, but many of those are scheduled to upgrade over the next 2 years.

Edit: The servers are 422, but the broadcasts are 420, as brigade points out. (The edit tag on my original comment has already expired. Grrr.)


ATSC only allows 4:2:0 in MPEG-2 (ATSC A/53 part 4 section 6.1.3) or H.264 high profile (which is restricted to 4:2:0).

I'm admittedly not familiar with other countries, but I would be incredibly surprised if any of them allowed 4:2:2.


Thank you, you are correct.

I've assumed that the video settings of the server is what they were delivering, but there must be a down-sample on the way to the transmitter. (Cablelabs is the other large distribution format that we encounter, which yields the same story.)




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