ffmpeg speed up video - Windows

Question

In manual it says:

ffmpeg -i input.mkv -filter:v 'setpts=0.5*PTS' output.mkv

But when I run:

ffmpeg -i input.mp4 -filter:v 'setpts=0.5*PTS' speedup.mp4

I get an error:

[AVFilterGraph @ 0000000002500600] No such filter: 'setpts=0.5*PTS'
Error opening filters!

Not sure if it means that filter can't be opened at all or simply this filter is not available.

How do I run it correctly? Or maybe my release does not support it, then where can I get the release that would work right? Win32/x64 binary

Answer 1

Use both setpts and atempo to speed up both video and audio:

ffmpeg -i input-video.mp4 -vf "setpts=0.68*PTS" -filter:a "atempo=1.467" output-video.mp4

From: https://trac.ffmpeg.org/wiki/How%20to%20speed%20up%20/%20slow%20down%20a%20video

You'll have to do the right math for the numbers, of course. The setpts needs to be smaller to make the video go faster, but atempo needs to be larger to speed up the audio.

Audio value needed = 1 / Video value

Answer 2

if you have your ffmpeg.exe (mine for windows) for ex you can list all the available filters with this command line, you can edit the txt file c:\filters.txt to see them.

ffmpeg -filters > c:\yfilters.txt

in mine i can se the filter SETPS (VIDEO TO VIDEO only):

setpts V->V Set PTS for the output video frame.

your command line is correct and work with the ffmpeg version that have this filter(try to download the latest version)

this command line works also for me : ffmpeg -i video_input -vf "setpts=factor*PTS" video_output

the factor can be :

1.for speeding the video 0.2,0.4,0.6,0.8..(<1)

2.for slowing the video:1.2,1.4,1.6,1.8,2.0,3.0,4.0,5.0,10.0... (>1)