Author Topic: youtube`s quality  (Read 955 times)

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Offline SoLoD

youtube`s quality
« on: December 30, 2016, 12:09:30 AM »
So, the question is about utube`s bitrate.
I have video with 10mbits, and after "youtube magic" i get only ~3 mbit video.
1. Can i get more, because i am looking at gtas videos and picture on it is just like in game.
2. Should i render in vegas with 3 mbits so youtube will not corrupt my video (will it help if i will make 3 mbits by myself instead of utube "help").

Offline Rusch69

Re: youtube`s quality
« Reply #1 on: December 30, 2016, 06:52:56 AM »
YouTube is always converting uploads in order so save disk space and bandwidth. Unfortunately there's no way around it. The maximum bitrate after uploading is determined by the video's resolution & FPS.

This table shows what YouTube recommends as targets.

Their bitrate cap will reduce quality a lot.

So, frame doubling & upscaling make a lot of sense for YouTube uploads. That way the converted video will have a higher bitrate and it'll look better in general.
As for the bitrate of the source file - the higher the better.
« Last Edit: December 30, 2016, 07:51:21 AM by Rusch69 »

Offline SoLoD

Re: youtube`s quality
« Reply #2 on: December 30, 2016, 07:05:09 AM »
So, thats why GTAS videos are looking better?
Can you tell me what bitrate avarage gtas video has with 720p on youtube?
And when you are saying bitrate of source file - do you mean file that already was rendered in vegas or just files that you are using in vegas?
Someone said, that if you want to upload 720p, you can make resolution a lil bit higher, so youtube will determine your file as 1080p and will give it more bitrate. Is that true?
About doubling frames - just do the final render in vegas with 60 fps instead of 25?
About upscaling - does it work for 4:3 videos? If i have 16:9, do i need to use it?

/e https://www.youtube.com/watch?v=-gVjJBhaiQ8
Are that black bars stands for "upscaling"? Can not get how it helps.
« Last Edit: December 30, 2016, 07:13:45 AM by SoLoD »

Offline Rusch69

Re: youtube`s quality
« Reply #3 on: December 30, 2016, 07:50:36 AM »
GTAS videos are looking shit on YouTube for the most part too, since pretty much none of us bothers with upscaling/frame doubling.

The bitrates for 720p videos will all be at a max of 3 MBit/s approximately. There's no average since it depends on the footage.

Bitrates and quality in general should always be kept at maximum level until the final lossy render.

That 720p to 1080p progress someone described to you is called upscaling. And yes, that allows higher bitrates. The bitrate is always tied to the resolution.

If you wanna use frame doubling, just double your frame rate in the final render. So 50 FPS instead of 25 FPS (SA) and 60 FPS instead of 30 FPS (VC).

Upscaling can be used for any aspect ratio. It's entirely up to youself whether you render at a higher resolution or not.

Just forget about black bars completely. Go with the aspect ratio you're comfy with. 16:9 is the standard tho.

Offline SoLoD

Re: youtube`s quality
« Reply #4 on: December 31, 2016, 12:04:20 AM »
About doubling.
So, i render at x2 frames and will get 7.5 mbit insteadd of 5.
I will have x2 bigger file size, because i will need to spend more mbits to draw "second frames". If i have 100 mbytes for 5 min video with 25 fps, can i say that each frame will get 100/300/25 = 0.013 mbytes for 1 frame, and when i will make 200 mbytes for 5 min with 50 fps, i will get the same 0.013 mbytes.
But i will need to render in vegas my 50 fps video with x2 bitrate to only make my 50 fps video look as good as 25 fps.
And when i will upload it to youtube, my 50 fps video will not be corrupted as hard as 25 fps.
Is it right?

About upscaling.
I never used it before, just what to clarify.
I get my picture, lets say it is 1360x768. In the vegas project i need to put 1080p, and then enlarge my 1360 x 768 pricture to 1080p size. Then i will render it with 1080p. And i will get even bigger file size.
Lets say im making my 1360x768 to 720p project and final render. And i get 100 mbytes. If i will use that 1080p project settings and final render, i will get 225 mbytes (1080p is 2.25 time bigget than 720p). Is it right?

And in youtube, when i will set 1080p quality, i will get 12 mbit/s, but when i will set same 1080p-rendered-video quality to 720p on youtube, i will get same old 7.5 mbytes?

So, final file size will be 1x2x2.25 = 4.5 times bigger than it was?


/e i forgot to say.
About doubleframing. I am uploading 25 fps video with 10 mbits, so utube will make it 5, i will get 5/25 = 0.2 mbit per frame.
And i am uploading the same 50 fps video with 20 mbits, utube will make it 7.5, i will get 7.5/50 = 0.15 mbit per frame.
So, my video will look even worse?
« Last Edit: December 31, 2016, 12:20:52 AM by SoLoD »

Offline Rusch69

Re: youtube`s quality
« Reply #5 on: December 31, 2016, 07:34:42 AM »
Forget about your MBit per frame maths, since that's not how video coding works. If you're interested in learning about encoding you should probably read up on macroblocks & I-/B-/P-Frames.



I'll just give a simple example, because otherwise you're not getting it I think. :P

Let's say you're making an SA video. Recorded your footage in-game in 1280x720 and 25 FPS. You then edit your footage in Vegas and render out the final video with these different settings:

  • 1280x720, 25 FPS, 20 MBit/s
  • 1280x720, 50 FPS, 20 MBit/s (frame doubling)
  • 1920x1080, 25 FPS, 20 MBit/s (upscaling)
  • 1920x1080, 50 FPS, 20 MBit/s (upscaling + frame doubling)

Now you're uploading them all to YouTube and they all get converted. Their bitrates will vary quite a bit:

  • Results in ~3 MBit/s
  • Results in ~4 MBit/s
  • Results in ~5 MBit/s
  • Results in ~6 MBit/s

These values are fictional, but it showcases roughly how it works. Increasing the frame rate and resolution only serves the purpose of maintaining a higher bitrate after YouTube's conversion.
Again, the table I previously posted is just YouTube's recommendation for the source files you're uploading. It's not showing the final bitrates after their converting process.

Offline SoLoD

Re: youtube`s quality
« Reply #6 on: January 01, 2017, 06:15:17 AM »
  • 1280x720, 25 FPS, 20 MBit/s
  • 1280x720, 50 FPS, 20 MBit/s (frame doubling)

  • Results in ~3 MBit/s
  • Results in ~4 MBit/s

So, will 25 fps with 3mbit look worse than 50 fps with 4 mbit?

Offline Rusch69

Re: youtube`s quality
« Reply #7 on: January 01, 2017, 08:41:17 AM »
Yes, it's all about the final bitrate in this case. The frame doubling doesn't require much extra data due to motion compensation.

Offline PK

Re: youtube`s quality
« Reply #8 on: January 01, 2017, 11:30:13 AM »
Yes, it's all about the final bitrate in this case. The frame doubling doesn't require much extra data due to motion compensation.

I'm curious to whether you go to film school, study computer science, or just is a computer-genius all-around.  :unsure:

Offline Rusch69

Re: youtube`s quality
« Reply #9 on: January 01, 2017, 01:27:16 PM »
I studied multimedia & communications with thematic priorities in media and 3D design. The basics studies included some file compression/encoding and IT stuff too, so yeah kinda.
I'm very interested in computer and entertainment hardware, so I read up news about that on a daily basis as well.

 

anything