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Rife w/ 10 bit 4k HLG iPhone video = flickering
#1
Was shooting some fill-in footage for my podcast this past weekend on my iPhone 14. 10 bit HLG bt2020 .mov's at 24p. It was more of an experiment really, just curious to see if I could even interpolate it with rife 4.6 to 48p or 72p. I tried using the footage straight from the phone, and then converting it first to x265 through ffmpeg. Either way, it seemed like it was dropping every other frame. If i converted it from .mov to x265 mp4 through Hybrid, THEN interpolated that mp4 I believe it worked correctly. Need to test that one more time. 

Dropbox link with 2 video samples [hope you like rap...]
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#2
Can you share a sample of such a source?
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#3
Sure, here's one of the clips straight from my icloud photos app-

Original iphone video

I think it could have something to do with iOs' variable frame rate. Was looking at some of the metadata on these clips and the frame rate is all over the place. Anyway to tell the encoder to lock the fps at 24 when converting to an editing format? Or should I just break down and use ProRes?
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#4
Mediainfo reports:
Frame rate mode                          : VFR
Frame rate mode                          : Variable
Frame rate                               : 22.295
Frame rate                               : 22.295 FPS
Minimum frame rate                       : 0.512
Minimum frame rate                       : 0.512 FPS
Maximum frame rate                       : 24.000
Maximum frame rate                       : 24.000 FPS
Argh, since the set fps is 22.295 directly interpolating with Hybrid would first decode to 22.295 and thus throw out some frames. Sad
Another problem is that the video is 24 seconds while the audio is 27 seconds,... :/

What you can do is:
Open the file in Hybrid, set audio&video to passthrough, set Muxing->Overwrite->Frame rate to 24, with this create an .mkv as output.
This will create a .mkv-file which still has the time codes, but the 'Frame rate' is reported as 24fps. (note: you will lose the rotation flag)
Then use that file as input in Hybrid, this way Hybrid will decode the file to 24fps, and you can use frame interpolation to get it to 48/72/...fps. The higher you go, the more interpolation artifacts you'll get.
You might want to enable "Crop/Resize->Misc->Misc->Rotate output" and set it to 90cw.
I suspect that you might lose the 3 seconds additional audio somewhere along the line of processing.

Cu Selur
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#5
That’s slightly embarrassing 😫 

As much as I wish I could use my phone for everything, I should probably go back to Canon DSLR’s and see if Magic Lantern is still active lately.. 

Thank you though, that’s a major help. Just checked, there is an option on here to drop frames while recording for low light/file size optimization.

Oh, wait. It wasn’t on to begin with 🙄

[Image: zYeYCC9_d.webp?maxwidth=760&fidelity=grand]
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