Recording: If there is no 25/50 fps setting what happens when viewing in a 50 Hz country?
- Thread starter benawhile
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- 50 hz fps refresh rate
TheBailzOnYT
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I am supposing you're saying that you are trying to move Video Tapes that are 25 fps to a mp4 recording? Any frame rate should be fine as long as there is enough resources to handle such rate.
If you record a video in 60 fps or 25 fps on OBS and decide to use a TV that is running at 50 Hz, if you're recording has less than 50 fps then the tv will just show the same frame over more refreshes (screen refreshes happen in under a second), if the recording was more than 50 fps then you'll just be losing some frames because the device is unable to refresh on time with the frame
Refresh Rate (Hz) is how many frames are displayed on a screen per second.
Frame Rate (FPS) is how many frames are being rendered.
Really?
What version of OBS are you running?
Anyway, there should still be this:
31fps is definitely not standard anywhere, but it'll take it and use it. So anything else should be okay too, like a standard that it doesn't know about, so long as your hardware can keep up.
Aaron: Thank you, I am using 30.2.3 64bit on Windows 10 laptop. Thanks to your screenshot I can now see those settings. But I haven't got that far yet. I was talking about on running for the first time you get Auto Config Wizard, also available under Tools, and that only gives a choice between 30 and 60. Needless to say I don't fully understand yet. Why are we talking about 31? As I am in UK, should I change the video setting from the Wizard default to 25 or 50? Anyway, I won't trouble you to tell me exactly what to do (yet!) I will try a few settings and see what works, as long as the old VCR I have still works. It was working a couple days ago, a used Phillips VR 200 I bought off Amazon about 12 years ago and only just fired up, lucky the belts hadn't rotted.
I don't either, why the wizard limits you to that. All it does though, is do some tests to preset a bunch of settings for you. So just pick something close for the wizard to use, and then fix the actual setting later.
It's something that I know is not standard anywhere, just to show that it's not limited to what it already knows about. That's all.
I'd say 50, and see if your hardware can keep up. It helps a lot to have a canvas that actually matches the incoming video, and not try to upscale. (fewer pixels per frame) I've seen some good subjective results from upscaling PAL to 1080p50 or NTSC to 1080p60, but you're technically not adding anything by doing that. If you record with good enough quality, then you can upscale it later and get the same result.
The reason to go with the faster frame rate is because it's interlaced, and you're going to convert it to progressive. (that's the i or p in 1080i or 720p or whatever) Interlaced draws all of the even lines in one scan, and all of the odd lines in the next scan, then even, then odd, etc. You have 50 scans per second for PAL, but only 25 complete frames if you must have *all* the lines before you count a frame. That, plus persistence of vision, gives a much better picture on the limited technology of the time, but presents a problem today because the two scans (and in fact every position on the screen) are still different moments in time.
So there are a bunch of de-interlacing algorithms to choose from, even in OBS. (right-click the capture source...) Play around with those, and their settings, to see which one gives the best result. Using the higher frame rate in OBS allows some of them to do all of what they're supposed to do, by filling in the missing lines to convert each scan into its own frame.
If it turns out that the best one for what you're doing, produces the lower frame rate, then each frame will simply be shown twice. If you happen to know that, then you can drop OBS to 25, but it doesn't hurt much to keep it at 50 and let it duplicate every frame. The encoding is based heavily on the difference between frames, so no-difference hardly takes anything in terms of bitrate or storage space. It does, however, require the computer to process/render each of those frames separately, just because it always does until it gets to the encoder. So the higher frame rate does require more work *while you're recording*, even if every frame is duplicated. Maybe that's significant for you, maybe not.
(Though if it *is* significant, then I would expect you to also have trouble with 1080p10, just by estimating the number of pixels per second. That's another benchmark test that you wouldn't actually use as-is, kinda like the 31fps above.)
Thanks, I started a TV course in the 1970s and learned about interlacing as it was then, albeit I only studied monochrome. I did no further studies and went in to a totally unrelated field, mental health nursing! I did some further industrial electronics, much enjoyed it, but the pull of the NHS was too great in the end!