With a bandwidth capacity of up to 18Gbps, it has enough room to carry 3,840 x 2,160 resolution video at up to 60fps. It also has support for up to 32 audio channels, "dynamic auto lipsync" and additional CEC extensions. The connector itself is unchanged, which is good for backwards compatibility but may disappoint anyone hoping for something sturdier
Maximum TMDS Throughput Per Channel: 6 Gbit/s (including overhead) / Was 3.4
Maximum total TMDS throughput: 18 Gbit/s (including overhead 8b/10b) / Was 10.2
Maximum actual Throughput: 14.4 Gbit/s (overhead removed) / was 8.16
Maximum audio: 36.86 Mbit/s / same
Maximum Color Depth: 48bit per pixel, / same
8b/10b overhead is from encoding the signal and ECC. Seems like a very steep overhead to me.
Good news though, it does support 2560x1600 @ 109 FPS, perhaps slightly less.
I am also not quite convinced of 60 FPS. @ 32bpp, it is only 54 FPS. 24bpp is 72 FPS.
One interesting thing while going through the Engadget comments was running into this gentleman:
@BuyudunBebegim 18 Gbps is apparently enough to fit 4K 120Hz.
4K 120Hz, using 4:2:2 chroma, is only 15.9 Gbps, though reduced blanking intervals would add at least 0.5 Gbps to the total. There's no technical reason why 4K 120Hz can't be achieved over HDMI 2.0, as long as you're willing to accept 4:2:2 chroma instead of 4:4:4 chroma. People are already successfully doing 1080p@120Hz over HDMI 1.3a (A few new models of HDTV's can accept true 120Hz now; no interpolation -- there's a list on the Net now.) and the HDMI clockrate isn't even being overclocked at all.
There's currently an initiative in a HardForum thread (SEIKI 4K thread, begining around approximately page 15) to come up with a 120Hz modification of an existing 4K panel, with some thousand-dollar pledges. We've discovered the panel is 120Hz capable, but the TCON is not; and we are trying to figure out if electronics parts on the market exists to bypass the TCON limitation... It would take probably several LVDS channels to pull this off, though. Some people are quite determined to see 4K 120Hz happen. We were looking at DisplayPort channels as the method, but HDMI 2.0 could actually make this easier.
Mark Rejhon (Owner of Blur Busters)
I was quick to chime in though the problems with overhead:
You are forgetting about 8b/10b overhead for ECC and encoding. You start with a maximum throughput of 14.4Gbit/s, unless you find a way to bypass ECC. As the imagesize gets larger, the more than likely ECC has to be used and it is proportional in bandwidth to the bandwidth of the transmission.
Or in other words, the more bandwidth you add, the more you need in encoding/ECC.
You could in theory with 4.2.2 get about 105 FPS, going off of your 15.9 Gbit/s
I wasn't quite sure where he got the 15.9 Gbit/s but the ratio of bandwidths of 15.9/14.4 in determining the lower frame rate supported being about (120 / (15.9/14.4)). I then rounded down about 4 FPS.
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