Score:1

mpv - How do I slow down ONLY 25fps videos to 24fps? I tried the "autospeed.lua" script but it's doing nothing despite other lua scripts working

kn flag

Much like how reclock worked on Windows, I want to be able to slow down ONLY 25fps videos to 24fps with the corresponding reduction in audio pitch in order to cancel-out any PAL speed-up (PAL speed-down?) while leaving videos that are already 24fps, 30fps, 50fps, 60fps, etc. to play back as-is without any speed and pitch alteration.

The usual go-to solution seems to be to use autospeed.lua (not to be confused with autospeedwin.lua) but, for whatever reason, it just seems to do absolutely nothing on my system despite using a really bare-bones mpv.conf file, not to mention that other lua scripts are working without issue (most easily confirmed by the pause-when-minimize.lua script).

My test mpv.conf file is so basic that the following 3 lines is literally (not figuratively!) all I have in it:

video-sync=display-resample
script-opts=autospeed-maxspeed=1.01
script-opts=autospeed-minspeed=0.9

(I don't even know if that would include the corresponding reduction in audio pitch that I also require but, at this point, I'm just trying to get things working at all)

This was tested using a specific 50fps video clip that I find to be extremely good for noticing judder re-encoded to 25fps (aka removing every other frame) and then making a second copy that was then encoded to 24fps by manually slowing it down a bit.

And, as a sanity check, I also tried taking the very same aforementioned encoded-to-25fps video clip and made another copy that's encoded to 30fps by manually speeding it up, and then made yet another copy that was encoded to 31fps, also by manually speeding it up.

With my monitor at either 60Hz or 120Hz, if things were working, I would think that the 25fps and the 31fps videos would be played at 24fps and 30fps, but they are not and are considerably more noticeably juddery compared to the 24fps copy and especially the 30fps copy, implying that autospeed is not doing anything.

(I even tried using the "script-opts=autospeed-osd=true" option under the assumption that it'd make things more obvious if the script is doing anything but, alas, no OSD showed up)

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