Originally Posted by macd23
And note that the reality is that 4K (aka UHD1) production really uses 1080/59.94p technology in groups of 4. So the GVG switcher has 192 HD inputs, but this drops to 48 UHD/4K inputs. This is because the UHD content is split into 4 separate 1080p feeds (usually 1/4 screen tiles) for routing, server record/replay and switching. If you want to do UHD production at the moment you use high-end HD production gear (other than cameras, monitors and in some cases recorders which are UHD) with your functionality quartered... (4 x 3G-HD-SDI connectivity for every UHD source/destination basically, so a 256x256 router becomes a 64x64 router, a 4-in, 4-out EVS XT3 becomes a 1-in, 1-out etc...) (*)
IP routing and I/O for switchers and servers may change this, though to give you an idea of the data rates involved with UHD/4K - you can't realistically get uncompressed UHD down 10GbE ethernet connections without mezzanine compression like VC-2...
An uncompressed 3840x2160/60p 4:2:2 10-bit source has a bitrate of around 9.95Gb/s (before any IP encapsulation etc.), rising to 1.8Gb/s if you use 4:4:4 12 bit (which is more likely to be used for high-end movie/drama acquisition - which is likely to be compressed in-camera - but will still require monitoring uncompressed).
And if you think those numbers are scary - remember Tokyo 2020 Olympic coverage is likely to be 8K UHD2 (as is some trial material shot at Rio 2016, just as was the case at London 2012)
UHD2 is likely to be 7680x4320/120p at 12 bit potentially - which is around 95Gb/s uncompressed at 4:2:2 12 bit, though I think NHK are using some trickery to get this down to 48Gb/s. (Those are Gigabit/second not Megabit/second figures...)
(*) For those of us old enough to remember the early days of HD this is very reminiscent of the original BBC/BTS system used to record HD digitally uncompressed using 4 x D1 3/4" SD uncompressed Digital VTRs. Rather than 1/4 screen tiles though, the HD picture was divided into 2x2 sample groups with each of these 4 samples recorded to a separate DVTR, so you got 4 full-screen 1/4 resolution (and very aliasy) recordings, one on each VTR. You could then edit in the SD domain using one of the 4 source pictures, create an Edit Decision List, and repeat the process automatically on the other 3 VTRs (usually using the 4VTRs as an edit suite). This allowed you to use some SD post production functionality to edit HD. Neat way of recording 1440x1152 (i.e. 720x576 x 4) without having to buy bespoke HD VTRs. <Sorry - very off topic >