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On February 20 2013 02:18 Cyro wrote:
Because lossless data takes up an extremely large amount of space, thousands of megabits per second. A modern 720/1080p stream will use something like 3mbits bitrate - there's a ton of compression. Bitrate is very simple, just the amount of data you are allocating for the encoded file output (if you set 5mbits, your video file will be 5mbits per second, 300mbits per minute) x264 has amazing efficiency and makes video look good at bitrates comparatively tiny compared to raw video, but you still need certain bitrates for a video to look good. At 1mbit for example, a 1920x1080 stream will get very pixelated, messy etc during motion but a 1280x720 stream might not nearly as much, because you have less than half as many pixels to deal with, it takes a lot less data. At 5mbits, the 1920x1080 stream would destroy the 1280x720 one, because you have 2.25x as many pixels and enough data assigned to encoding for the video to come out "ok"
If you mean you can have a better looking 720p stream than a 1080p stream if you use for example 2mbit bitrate for the 720p one and 1mbit for the 1080p, thats pretty simple logic once you know how to look at it.
The 100MB video unless something is wrong will look a lot better than the 50MB one
Thanks. Can I infer from this that there's a ration between bitrate and resolution that might be considered "appropriate"?
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On February 20 2013 02:03 Gumbi wrote:Show nested quote +On February 20 2013 01:22 z0rz wrote:Bitrate is the amount of data being streamed (usually measured in "kilobits per second" or "kbps" in streaming applications). Higher bitrate = better looking stream. Resolution is the number of pixels being displayed. 1080p is 1920x1080. (width x height), 720p is 1280x720, etc. Frankly, I doubt you need to bother yourself with learning what bit depth is. It's pretty irrelevant from a streamer perspective, but I guess you could skim the pictures at least: http://en.wikipedia.org/wiki/Color_depth That's not particularly helpful. How are the two related? I thinjk ih can have a nicer looking 720p stream compared to a 1080p one if the bitrate is higher, why is that?
Well, it's complicated. We're talking about both objective and subjective things here (1000 kbps is obviously less than 2000 kbps, but it's hard to mathematically prove if X stream LOOKS BETTER than Y stream).
Generally speaking, higher resolutions require higher bitrates. It gets confusing when comparing different resolutions because (totally using arbitrary numbers here so take this with a grain of salt) a 1200kbps 720p stream could look better than a 1500kbps 1080p stream. Stationary things like text and HUDs/overlays will look sharper in 1080p, but there will be more pixelation in 1080p at lower bitrates since there isn't enough data to "fill in the gaps".
There are general guidelines for which resolution you should stream at with a certain bitrate, but it's better to just test it yourself and see what looks better to you (or if your computer can actually handle streaming at higher resolutions). Also keep in mind that we're talking about the resolution set in OBS and not the resolution set in your game. Example: you're playing SC2 in 1920x1080 but have OBS set to 1280x720 (1.5 downscale), so your stream is being displayed at 720p.
This probably isn't the best analogy, but it's the first thing that came to mind: say you have a 20ft by 20ft canvas and a 40ft by 40ft canvas. If you took the amount of paint needed to cover the 20ft canvas, you wouldn't have nearly enough for the 40ft canvas. The 40ft canvas obviously needs more paint (bitrate) to account for its larger size (resolution). However, if you have enough paint to finish the 40ft canvas then the choice is easy.
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Thanks! So lets see if I have this somewhat correct:
Very simplistically, resolution might be considered "space" and bitrate might be considered "information". With certain amounts of information,you can support certain amounts of space. When we input the subjectivity aspect, there is a blurred line between resolutions. Say at 2 megabits/s, someone might consider this to be better at 1080p, another might at 720p (arbitrary number). EVERYONE might consider 1megabit at 1080p bad because of so much pixelation (too little information spread over too much space). Is this roughly correct?
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On February 20 2013 02:46 Gumbi wrote:Show nested quote +On February 20 2013 02:18 Cyro wrote:
Because lossless data takes up an extremely large amount of space, thousands of megabits per second. A modern 720/1080p stream will use something like 3mbits bitrate - there's a ton of compression. Bitrate is very simple, just the amount of data you are allocating for the encoded file output (if you set 5mbits, your video file will be 5mbits per second, 300mbits per minute) x264 has amazing efficiency and makes video look good at bitrates comparatively tiny compared to raw video, but you still need certain bitrates for a video to look good. At 1mbit for example, a 1920x1080 stream will get very pixelated, messy etc during motion but a 1280x720 stream might not nearly as much, because you have less than half as many pixels to deal with, it takes a lot less data. At 5mbits, the 1920x1080 stream would destroy the 1280x720 one, because you have 2.25x as many pixels and enough data assigned to encoding for the video to come out "ok"
If you mean you can have a better looking 720p stream than a 1080p stream if you use for example 2mbit bitrate for the 720p one and 1mbit for the 1080p, thats pretty simple logic once you know how to look at it.
The 100MB video unless something is wrong will look a lot better than the 50MB one Thanks. Can I infer from this that there's a ration between bitrate and resolution that might be considered "appropriate"?
Yes you can. There are some nice charts out there which are easy to find. For a 720p stream 2750 kbps is optimal (meaning more bitrate doens't make the video look that much better), for 1080p it's something like 3750 I think. I'd just do 4k if I was streaming 1080p. You can use the calculator on the OBS homepage to get a good idea what you should be using.
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On February 20 2013 03:36 Gumbi wrote:
Thanks! So lets see if I have this somewhat correct:
Very simplistically, resolution might be considered "space" and bitrate might be considered "information". With certain amounts of information,you can support certain amounts of space. When we input the subjectivity aspect, there is a blurred line between resolutions. Say at 2 megabits/s, someone might consider this to be better at 1080p, another might at 720p (arbitrary number). EVERYONE might consider 1megabit at 1080p bad because of so much pixelation (too little information spread over too much space). Is this roughly correct?
Yeah that's basically it. There are a lot of grey areas because there are so many factors that go into determining a stream's output quality (another example: at the same bitrate, 1080p @ 30fps will look better per-frame than 1080p @ 60fps, but some people might prefer the smoothness of 60fps instead of the cleaner picture of 30fps).
You can TRY to make guidelines, but there are too many variables for a one-size-fits-all answer. IMO it's best to just explain what each setting/number does and educate users so they can optimize their own unique computer and internet connection with their own unique goals of streaming.
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Cool, thanks a lot! Is there a reason why each frame looks poorer in a 60FPS video as opposed to a 3FPS one?
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On February 20 2013 06:45 Gumbi wrote:
Cool, thanks a lot! Is there a reason why each frame looks poorer in a 60FPS video as opposed to a 3FPS one?
In case you are using the same bitrate for 60fps and 3fps (it's 30fps, right?), then yeah, don't be surprised.
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On February 20 2013 06:54 HomeWorld wrote:Show nested quote +On February 20 2013 06:45 Gumbi wrote:
Cool, thanks a lot! Is there a reason why each frame looks poorer in a 60FPS video as opposed to a 3FPS one? In case you are using the same bitrate for 60fps and 3fps (it's 30fps, right?), then yeah, don't be surprised.
I meant to say 30 FPS. Another poster said that though 60 FPS looks smoother, each frame won't look quite as good as a 30FPS stream.
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There are twice as many captured frames fighting for the same total bitrate. I don't know exactly how it works, but I don't think it's as bad as "double the framerate = half the quality".
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On February 20 2013 07:56 z0rz wrote:
There are twice as many captured frames fighting for the same total bitrate. I don't know exactly how it works, but I don't think it's as bad as "double the framerate = half the quality".
I assumed that, just wondering what's going on then in such a case 
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United Kingdom20328 Posts
If you have 1000 apples and split them between 30 people instead of 60, each person has more
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On February 20 2013 09:51 Cyro wrote:
If you have 1000 apples and split them between 30 people instead of 60, each person has more
But each frame isn't "half as bad" is it?
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United Kingdom20328 Posts
Thats a complicated question, both yes and no depending on how you look at it
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Not really, the frames definitely aren't half the quality since you have lower amount of motion vectors to encode, and the higher frame rate gives the eye less time to perceive the per-frame quality loss.
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Hey, if my upload speed is terrible but my PC could otherwise handle a high quality stream, is there a way to use OBS to create a VOD instead and just upload the video over the course of a couple hours to Twitch/Youtube?
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Hey Guys,
I'm running an i7-2700, GTX 670, 16 GB RAM and have League installed on my SSD. When I have OBS streaming I usually get about 100-150 FPS in game (full screen windowed), but the game itself is very choppy, like it's dropping frames. Tried turning vsync on but that just drops my FPS to the 40s realm. Tried during down every setting and the gameplay is still choppy while playing.
Grabbed all my OBS settings from the calculator. Been looking around and I'm at a total loss.
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+ Show Spoiler +On February 14 2013 21:05 Eisregen wrote:Hey guys, first I wanna thank you for OBS, which is an amazing piece of software, thanks!! Streaming with it is really comfortable and less ressource wasting. Streaming works like a charm with SC2 etc. The only problem I have, is streaming BF3. I absolutely fail to capture the sound of BF3. The video is fine, but the stream has no game sounds at all. I stream my mates and myself on ts, but no ingame sounds. Does anyone know why this is? My Speccs: Phenom II 955@3,6GHz HD6870 8GB DDR3 Asus Xonar D1 ![[image loading]](http://speedtest.net/result/2407457790.png) Game Speccs: High Settings (shadows and other useless stuff on low or off) 1900x1200 Streaming settings: Res.: 640x400 FPS: 25 CPU preset: veryfast Quality: 8 Aero disabled Audio device: Standard Audio Quality: AAC 128bitrate 44.1kHz Example I just recorded: http://de.twitch.tv/eisregen/b/367249157Thanks for your help, very appreciated.
Nobody has an idea?
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So... what if I do all of the above and get a black screen in preview/stream... streaming league of legends, mind you. Any ideas on how to fix that? K thx <3
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On February 20 2013 18:39 Renalan wrote:
Hey Guys,
I'm running an i7-2700, GTX 670, 16 GB RAM and have League installed on my SSD. When I have OBS streaming I usually get about 100-150 FPS in game (full screen windowed), but the game itself is very choppy, like it's dropping frames. Tried turning vsync on but that just drops my FPS to the 40s realm. Tried during down every setting and the gameplay is still choppy while playing.
Grabbed all my OBS settings from the calculator. Been looking around and I'm at a total loss.
LoL runs like complete ass for me if I stream with borderless/windowed. Try playing fullscreen and using Window Capture or Game Capture. This should help switch scenes in between games.
On February 21 2013 04:53 Eisregen wrote:+ Show Spoiler +On February 14 2013 21:05 Eisregen wrote:Hey guys, first I wanna thank you for OBS, which is an amazing piece of software, thanks!! Streaming with it is really comfortable and less ressource wasting. Streaming works like a charm with SC2 etc. The only problem I have, is streaming BF3. I absolutely fail to capture the sound of BF3. The video is fine, but the stream has no game sounds at all. I stream my mates and myself on ts, but no ingame sounds. Does anyone know why this is? My Speccs: Phenom II 955@3,6GHz HD6870 8GB DDR3 Asus Xonar D1 Game Speccs: High Settings (shadows and other useless stuff on low or off) 1900x1200 Streaming settings: Res.: 640x400 FPS: 25 CPU preset: veryfast Quality: 8 Aero disabled Audio device: Standard Audio Quality: AAC 128bitrate 44.1kHz Example I just recorded: http://de.twitch.tv/eisregen/b/367249157Thanks for your help, very appreciated. Nobody has an idea?
Make sure BF3, TS, and OBS are all set to the right 'default playback device' which should be your headset/speakers. Also, check the 'Communications' tab in Windows Sound settings and make sure it's set to "do nothing."
On February 21 2013 17:02 Darkn3ss wrote:
So... what if I do all of the above and get a black screen in preview/stream... streaming league of legends, mind you. Any ideas on how to fix that? K thx <3
You're probably trying to use Monitor Capture with LoL in fullscreen mode (you would need to use Window Capture or Game Capture in OBS for fullscreen non-borderless games). I noticed when I was enabling/disabling Aero a lot to test different capture methods, it would basically lose the contents of my Game Capture source (black screen) and I would have to re-add it, so just re-create the source in OBS if you think that's the problem.
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On February 20 2013 17:54 DomovoiP wrote:
Hey, if my upload speed is terrible but my PC could otherwise handle a high quality stream, is there a way to use OBS to create a VOD instead and just upload the video over the course of a couple hours to Twitch/Youtube?
Yes, you can use OBS to record directly to your harddisk (local recording) and upload the video afterwards at your own pace. I don't think Twitch allows you to upload VODs, but YouTube obviously does (and it has a better interface for watching VODs anyway).
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EPT
