4K UHD HDR 28" display, connected to RX 570 4GB (Asus). Why are 720P Twitch streams blocky, full-screen?

[VirtualLarry]

I'm asking for a friend, that I recently upgraded.

He asked me this question, and I don't think that I gave him an adequate answer.

He thought, "hey, display is higher-res, everything should look SHARPER". Including 720P Twitch streams, that look fine not upsized on the monitor, but when you upsize them full-screen, they look "blocky" during action. Non-action parts of the screen like the life bars and stuff, ARE sharp.

Is there something wrong with the video drivers? (Win7 64-bit, AMD Adrenaline 19.4.1 drivers 4/3/2019)

 

[maddogmcgee]

Far from an expert but why would it look better without extra processing? It's the same low quality stream blown up on a large monitor. 720p even looks crap on my 1080p TVs.

1080p has a quarter as many pixels as 4k. I don't even wanna know how much less detail there is in the 720p video. I would imagine parts of the image like life bars are mono-coloured blocky sections that hide the lack of detail. You can see similar things on low bit rate cartoons. For anime 480p is actually watchable as they are big blocks of slow moving colour while for films it is horrible.

 

[pj-]

Blocky during action means video compression artifacts

The display can't do anything about those

Tell your friend to watch streamers that use higher res and higher bitrate video

 

[VirtualLarry]

Tell your friend to watch streamers that use higher res and higher bitrate video

That's basically what I told him. I said, "You want to experience 4K? Look up some 4K videos on YouTube."

He was like "Isn't there something in the monitor that makes everything look 4K?"

Edit: It should probably be said here, that the PC watching the video streams with Firefox, was set to 150% resolution display scaling, which may have added extra processing to the video frames from Windows, due to display scaling, that may not be able to be smoothed out properly by the monitor or video drivers.

Hooking up a PS4 (non-Pro) to it using HDMI, shows in the PS4 system menus still only as 1080P max res, but the BenQ monitor scales it up to 4K nicely, and IMHO does look maybe a tad sharper, than on his 43" 1080P TV.

 

[Stuka87]

Most twitch streamers use really junk compression, which causes lots of artifacts. People that know what they are doing run a dual PC setup where one PC is JUST doing the video compression.

Also, 720P has to be stretched a LOT to display at 4K. There are streamers that output 4K video, but its at a pretty low quality because of the bandwidth required. Those that run high quality video are typically like 860P or so, which actually provides better quality video than a higher resolution at a lesser data rate.

 

[VirtualLarry]

Also, 720P has to be stretched a LOT to display at 4K.

Exactly. I told him that Windows would look better, sharper, but I never said his Twitch streams would, only that: 1) He could now watch 4K YT, and 2) He could probably watch 4x 1080P Twitch streams at once. (He likes to have multiple streams open.)

His mind muddies things a lot, and I think that he only picked out "sharper, 4K, and Twitch", and came up with his own understanding, thinking that the 4K screen would make his Twitch streams sharper.