Whatever happened to 4K? The rise of “Ultra HD” TV

Companies seem averse to calling their latest TVs 4K.

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[freefall722]

I think the term 4K is confusing. Until very recently, I thought that 4K meant around 4000 line resolution as we always refer to current resolutions by mentioning the number of lines (720p, 1080p) I simply assumed they also referred to the number of lines and not to 4 times the area in pixel as it is actually the case.

The term 4K does have a logic to it though - it's just not related to the vertical resolution like 720p and 1080p are but to the horizontal resolution.

And yes that also means the 3840 horizontal lines of UHD doesn't quite meet the definition of 4K.

 

[freefall722]

They are going to be using the red ray codec, supposedly have had a break through and got it way down on bandwidth 2.5MB a second for streaming 4k video
http://www.redgrabs.com/up/1354328970.jpg

That's not nearly enough data. Need closer to SATA2/3 speeds. each frame of 4k is soumthing like 45MB is sze @ 25fps....

Raw 8bit 4k would be roughly 25MB per frame or 750MB per second (30fps) - way to much for current transmission. Keep in mind though that so is the 178MB per second (30fps) that raw 8bit 1080p transmission is. That's where compression comes in. Netflix is streaming those 1080p signals at around 2.5 Mbps so using the same compression 4k would come in at 10Mbps. (becomes more complicated because since the pixels are closer they can be compressed more because of them sharing similar data)

4k transmission at 30fps (or more film friendly 24p) will only be twice as much data as 1080p transmission at 60p so it'll be less of a jump from what we have now than it seems.

Note: The 45MB per frame size comes from Red shooting 16bits per channel - I use 8bit here because all our TV sets are 8bit or less. The extra data the Red shoots is for color correction