Confused about frame rate/resolution combination

[MrMysterious]

Hi community,

as I am just examining a video clip I have trouble understanding certain values. I am an amateur when it comes to the technical specs of a recording and so I need some help.

Starting point is a clip that - according to my diagnostics tool - was recorded with a framerate of 120fps. This might be true as of today there are devices that are able to do so.
What is confusing me though is the resolution of 480 pixels*848 pixels. What sense would it make to record 120fps with that bad resolution?
So my overall question is - as far as one could tell from the values attached in txt-file underneath - if this was recorded original in that way or if this was post-processed?

another mystery is the following: the clip in question captured a screen which shows another clip played in time lapse.
that captured clip has a timecode in it and one second of that clip equals 56 frames of the recording@120fps. So the captured clip has almost(!) double speed, right? But how do we get that 56fps? Shouldn't it be 60fps? Where does the odd framerate of 56 come from?



Hope someone can clear thigs up a little.

Cheers
MrM.

[davexnet]

That was post-processed since it mentions 2-pass rate control

[MrMysterious]

thanks for answering,

That was post-processed since it mentions 2-pass rate control

could this have happened to the clip when it was uploaded on social media?

[davexnet]

Yes most likely, Youtube, Social media in general always re-encode the incoming videos...

[MrMysterious]

Thank you for answering,

is 120fps and a resolution of 480 pixels*848 pixels a possible combination anyway? Is it common to use this?

Cheers
MrM.

[jagabo]

Yes most likely, Youtube, Social media in general always re-encode the incoming videos...

I'm not aware of any site that reencodes with 2-pass encoding with x264. So the video must have been reencoded by somebody offline.

is 120fps and a resolution of 480 pixels*848 pixels a possible combination anyway?

Any resolution and any frame rate is possible.

Is it common to use this?

No. But anime is sometimes encoded at 120 fps. This is because anime is sometimes a mix of 12p, 24p, 30p and 30i (60 pictures per second). And 120 is an integer multiple of all those (12*10, 24*5, 30*4, and 60*2), giving the smoothest playback.

[MrMysterious]

Thank you for the interesting input@all.

[video.baba]

With 480 x 848, the first thing that comes to mind is that it has been recorded on a phone in portrait mode.

[MrMysterious]

With 480 x 848, the first thing that comes to mind is that it has been recorded on a phone in portrait mode.

thank you. that is most likely the case. But I always wonder why people give away 2k, 4k or higher quality for such a shit.