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YouTube Format IDs

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Re: YouTube Format IDs

#61

Post by jasomill »

r_lee wrote: post #43
kccqzy wrote: post #15

Earlier quoted context omitted.

I’m the opposite. I take videos with 24fps, the standard for film. Lower frame rate gives me that film-like look which suggests sophistication, but 60fps feels like unedited screen grab or raw footage from a camcorder. I can’t explain it: it could be a case of acquired taste.

yeah strangely 50-60fps feels "unnatural" In a way? like uncanny valley sometimes?

More like a "canny valley", you're accustomed to movies looking like movies, not windows into reality.

You probably don't get the same feeling when watching live events.

I have a similar problem with 3D movies, shallow focus drives me nuts, because unlike in a 2D movie, I expect whatever I'm looking directly at in 3D to be in focus.

Re: YouTube Format IDs

#62

Post by ErroneousBosh »

edgineer wrote: post #40
ErroneousBosh wrote: post #28

Earlier quoted context omitted.

The neat thing is that 25fps content played out at 50fps doesn't use a lot more bandwidth than 25fps played out at 25fps because it only has to update every second frame, assuming identical noise between frames. And then you can go to field-per-frame 50fps footage when you need to say "camcorder".

It takes twice the file size to double the framerate without reducing visual quality of the original frames, whenever I try, with HEVC, AV1, etc. I can take a lower framerate video, run some software of constant size to interpolate the frames, and play back at a higher rate, but in practice I can't save that higher framerate video to a new mp4 file with small or constant size increase. It's got to be about linear.

Are you doubling up frames for 25fps-in-50fps though? Because with long-GOP codecs like HEVC there ought to be just about no difference between pairs of frames. For sure with intra-only codecs twice the frame rate will be twice the file size.

Re: YouTube Format IDs

#63

Post by ErroneousBosh »

nosrepa wrote: post #49
ErroneousBosh wrote: post #37

Earlier quoted context omitted.

There is absolutely no reason for any sane video editing software to be able to read VFR files. It should, however, reject them gracefully but positively.

I read that last bit in Hank Hill's voice.

We sell codecs and codec accessories.

Re: YouTube Format IDs

#64

Post by jasomill »

edgineer wrote: post #40
ErroneousBosh wrote: post #28

Earlier quoted context omitted.

The neat thing is that 25fps content played out at 50fps doesn't use a lot more bandwidth than 25fps played out at 25fps because it only has to update every second frame, assuming identical noise between frames. And then you can go to field-per-frame 50fps footage when you need to say "camcorder".

It takes twice the file size to double the framerate without reducing visual quality of the original frames, whenever I try, with HEVC, AV1, etc. I can take a lower framerate video, run some software of constant size to interpolate the frames, and play back at a higher rate, but in practice I can't save that higher framerate video to a new mp4 file with small or constant size increase. It's got to be about linear.

Surely this is a limitation of the encoder or a configuration problem, as encoding a video with faster motion at equivalent quality ordinarily requires a higher bit rate, and from the standpoint of the encoder, I wouldn't expect there to be a difference between half the frame rate and everything moving twice as fast.

Re: YouTube Format IDs

#65

Post by account42 »

kccqzy wrote: post #41
OGWhales wrote: post #22

Earlier quoted context omitted.

Movies are made by professional videographers that take care to limit the downsides of low fps, such as stuttering (still, sometimes movies will pan too fast and the stuttering makes it painful for me to watch). YouTube is very different, there are lots of amateurs and many of the videos don't need to make people feel like it's a movie. It doesn't seem the soap opera effect really applies when it's just a guy showing…

Right. And if a person knows they are shooting at 24fps they will take greater care to ensure they won’t pan too quickly. Panning too quickly is just bad video, whichever fps you choose.

No, panning quickly is done to give a high action feel.

24 FPS movies still do it, they just increase the exposure time so everything turns into a blurry mess - and often even that is not enough to hide the insufficient frame rate.

How fast you can pan also not only depends on the frame rate but also on the angular size of the screen so will be different for each fewer. Thus its better to use a higher frame rate to give more room to account for different viewing environments.

Re: YouTube Format IDs

#66

Post by account42 »

kccqzy wrote: post #15
mrob wrote: post #11

Earlier quoted context omitted.

I'd personally rather watch 480p60 than 1080p30. There's a lot of material in which spatial resolution is mostly irrelevant (e.g. presentations, which involve people talking and slides designed to be legible from a distance), but low framerate always looks unnatural and distracting, even after speeding it up by 1.75x or 2x. 60fps should be considered a bare minimum, not "high framerate".

I’m the opposite. I take videos with 24fps, the standard for film. Lower frame rate gives me that film-like look which suggests sophistication, but 60fps feels like unedited screen grab or raw footage from a camcorder. I can’t explain it: it could be a case of acquired taste.

Have you also decried the reduction in film grain, the addition of color and before that noises. All of those were claimed by people used to them to be essential to the film experience. Same for higher frame rates - if movies started using them more people would adjust to fix their preconceptions.

Re: YouTube Format IDs

#67

Post by account42 »

jasomill wrote: post #61
r_lee wrote: post #43

Earlier quoted context omitted.

yeah strangely 50-60fps feels "unnatural" In a way? like uncanny valley sometimes?

More like a "canny valley", you're accustomed to movies looking like movies, not windows into reality. You probably don't get the same feeling when watching live events. I have a similar problem with 3D movies, shallow focus drives me nuts, because unlike in a 2D movie, I expect whatever I'm looking directly at in 3D to be in focus.

Yes, that's also why depth of field effects in games always look wrong and distracting.

Re: YouTube Format IDs

#68

Post by account42 »

noir_lord wrote: post #6
throw0101d wrote: post #4

> HFR stands for "High Framerate", which means up to 60 FPS, whereas non-HFR is limited to 30 FPS Personally I find most ((almost?) all?) >30fps generally unnecessary and just chews through bandwidth, monthly (mobile) data caps, and processing/batteries. Are there specific cases where "HFR" videos are really improving the viewing experience of particular (types of) content? (Note: in the table it's about support for…

Gaming footage/videos, some games are so fast they are noticeably better to play at (and watch at) 60fps over 30fps.

The main limitation on YouTube for fast movement is actually bitrate. Perhaps they allow higher bitrates for 60FPS videos though.

Re: YouTube Format IDs

#69

Post by pebble »

bigstrat2003 wrote: post #53
quirino wrote: post #21

Earlier quoted context omitted.

I think many people would consider 60fps to be a minimum and 30fps to be almost disorienting, even for casual games. Gamers often go for 120-240Hz monitors even.

No, not very many people would say that. Console games for many years were 30 FPS tops, and people were just fine with it. It's only a small but vocal minority that insists on 60 FPS as some kind of minimum.

Speak for yourself bud.

Re: YouTube Format IDs

#70

Post by account42 »

jasomill wrote: post #60
gucci-on-fleek wrote: post #50

Earlier quoted context omitted.

> Most displays are 60Hz This was true even a couple years ago, but these days, most mid-range and above TVs [0], phones [1], and monitors [2] support 120Hz, which is a nice integer multiple of 40Hz. But lots of these devices default to 60Hz (or slower), so you can't really rely on most people having this enabled. [0]: https://www.rtings.com/tv/tools/table/196699 [1]: https://www.gsmarena.com/results.php3?nDisplayFra…

But not of 23.976 or 29.97, alas.

TVs will almost certainly support either those frame-rates or a multiple of them like 119.88. And some even support variable frame rates so a "120 Hz" mode could display effective any frame-rate below that with precise timings.
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