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4k Ultra HD smooth video playback

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Dewitts said:
Download "Realplayer" it has a built in downloader and comes with a free converter too.
I'm in the process of downloading the file from youtube though it claims 4k it's 4:30 long and 792 mb.
That's wrong surely????
Click to expand...

Unless my math is off, that is still highly compressed 4k content.

Assumptions/math:
- each frame in 4k video has 4x the number of pixels as does 1080p
- BD video tops out around 30mbit/sec
- 4x 30mbit/sec is 120mbit/sec, which is about 15MB/sec
- 4:30 is 270 seconds (4.5*60)
- 270 seconds of video at 15MB/sec is 270*15 = 4050MB (what the file would be if it was 4k at BD quality compression)
- your clip is 2.93MB/sec (which I see as compressed down to approx. BD quality 1080p)

In other words: Not really 4k content. It has been significantly compressed to where it is likely no better than good quality 1080p content (eg. content from a BD).

I generally don't care for things from RealNetworks, but will try RealPlayer... Thanks for the tip!
 
Just watched it back and the realplayer itself seems to jump a few frames every 4 or 5 seconds and says it's playing at 2.5 mb/s so as you said it's not true 4k format.

I watched it on VLC and it was much smoother and had very little judder (so assumably a good fps). The colour on the display looks brilliant and the definition is very clear though on my LCD tv the colours weren't so vibrant but I think that was due to the incorrect settings for my hdmi 3 input (my tv has different brightness, contrast, sharpness controls for each input. I set it for normal use with my laptop so it wasn't 'too extreme').

I am wondering if there would be any improvements by trying it via windows and making use of the radeon card instead of the hd3000?

Ultimately I think a genuine full 4k file should be sourced and not one uploaded to youtube.
 
Well i've looked for full 4k files and so far without going back to youtube for compressed mp4 versions i've only managed to find 1 place with what seems the genuine test files.
http://www.elementaltechnologies.com/resources/4k-test-sequences
They're short, don't look very interesting but i'm going to try downloading one and see if the probook can handle it. My money is on no because of the disk speed limitations lol.
 
Dewitts said:
Well i've looked for full 4k files and so far without going back to youtube for compressed mp4 versions i've only managed to find 1 place with what seems the genuine test files.
http://www.elementaltechnologies.com/resources/4k-test-sequences
They're short, don't look very interesting but i'm going to try downloading one and see if the probook can handle it. My money is on no because of the disk speed limitations lol.
Click to expand...

I looked at just the on titled 'Foreman'. Even it is still only 3.9MB/sec, so still no where near the "compression quality" of BD...

Note: Disk speed is not the issue here. Even slow HDDs can sustain ~80MB/sec reads, so 15MB/sec would not be a problem. The problem is decoding/moving all those pixels into place.
 
Was that the uncompressed yuv version or the compressed mp4??
 
Dewitts said:
Was that the uncompressed yuv version or the compressed mp4??
Click to expand...

Compressed.

Uncompressed is truly uninteresting to normal people... except for very high-end purpose built machines to edit big dollar video (think Hollywood movies). A full length uncompressed 4k 90-minute movie would use an entire 2TB HDD.
 
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