Upscaling to 4K for YouTube and Vimeo

[hateom]

I know this topic comes back over and over but I decided to test it out once again as the compression algorithms on YouTube and Vimeo change from time to time.
Even the videos that are already uploaded get re-compressed occasionally.
In this post I present the current state of the compression results and I try to show if it's worth to upscale 1080p video to 4K (even just for 1080p playback).

• 2160p 50mbps vimeo | youtube (1080p upscaled to 4K)
• 1080p 10bmps vimeo | youtube (default bitrate)
• 1080p 50mbps vimeo | youtube (increased bitrate)

Because the 4K video was rendered using 50bmps bitrate I wanted to see if there is any difference between 10bmps and 50mpbs of the 1080p video.
Here’s 100% crop of the face details (click to zoom in):



The difference between 1080p in both YouTube and Vimeo is very small. Both services compress the image quite a bit and we can see a lot of artifacts in the background. Increasing the bitrate doesn’t change anything – the video is re-encoded on the server anyway so there is no point in uploading a bigger file.
The last column with the 4K clips looks way better than 1080p versions. Let’s have a closer look.

1080p playback

Below is the comparison of 1080p clip and 4K clip both played at 1080p at youtube:





We can clearly see that even for playback at 1080p the difference in quality and sharpness is huge. This is true for both Vimeo and YouTube.

You can read a bit more about the topic and the workflow on my blog here:
timeinpixels.com/2016/07/upscaling-1080p-videos-youtube-vimeo/

Hope this helps someone! Let me know what you think.

[Lars Steenhoff]

If you upload to youtube or vimeo in the Prores codec it will look even better, or a similar supported higher quality codec.

As you stated the file is recompressed, however it does not mean you should not feed it the least compressed source file.

[hateom]

Yes, h.264 compression will be applied only one in this case.
I didn't compare h.264 vs prores in 4K - I guess there will be a difference, but probably not that significant (will try to test it sometime soon).

[dude]

Just to understand- do you mean real 4k footage, or is this trick all about scaling up 1080p footage to 4k in post with better results on vimeo and youtube with 1080p playback?

[hateom]

Upscaling 1080p to 4K vs uploading original 1080p. The former looks way better.

[DeafEyeJedi]

Digging your work in here @hateom ... You've nailed this one down nicely and actually confirmed which worked best for playback quality especially within Vimeo.

Thanks for sharing!

[dude]

Got it. Seems like i have to reconsider my corrent uploading process

[Flocksock]

interesting. would be nice to have a tutorial for upscaling to 4k in Resolve, too.
i mean... i just can set it up to 4K and stretch the image to it. (have to do some test, too)

[hateom]

I think it's enough to set up the project to 4K in Resolve.
RAW footage will be debayered directly to 4K and non-RAW footage will be upscaled.
I cannot demonstrate it as I am using free version of Resolve (supports only 1080p).

[jmanord]

I am using Resolve 12.5, which allows you to use a 4k timeline and 4k export. I wouldn't think setting the project to a 4k timeline vs 1080p timeline would have any effect on 4k rendered output. But, unless someone beats me to it, I will attempt to test it out and see as I have no evidence to support that claim.

[hateom]

I can't find the reference now, but I read somewhere that when the timeline is set to 4K the RAW material is debayered to 4K directly which results in slightly better quality than debayering in 1080p and upscaling for the render. There's not gonna be more details magically, but perhaps some sort of sharpening is added in the process or something like that. But sadly I haven't seen any samples or comparisons. Gotta test it out. Wasn't aware that the latest Resolve allows 4K timeline and render in free version!

[JADURCA]

Interesting work @hateom. Read your blog, thanks for your time and sharing your findings. One question. Did you use any unsharp mask when rendering 1080p material too? If not, then I think is not a fair comparison adding unsharp mask to the upscaled 4k and not to the 1080p.

Thanks @DeafEyeJedi for the updating as always.

[hateom]

Fair point @JADURCA. I didn't see noticeable difference in 1080p upload when adding unsharp mask and eventually I didn't use it in that version.
But for the sake of the test I probably should have.
I will try to re-upload 1080p videos with unsharp mask applied when I have a moment.