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Need to speed up video with MLT. I can do it with ffmpeg:

-filter:v "setpts=0.5*PTS"

But what about MLT?

user2455079
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1 Answers1

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The "timewarp" producer in MLT can change the video speed.

https://www.mltframework.org/bin/view/MLT/ProducerTimewarp

To double the speed (play faster) use:

$ melt timewarp:2.0:file.mp4

To half the speed (play slower) use:

$ melt timewarp:0.5:file.mp4

To speed up part of the file, you would have to split it up with in/out points:

$ melt file.mp4 in=0 out=29 timewarp:2.0:file.mp4 in=60 out=238 file.mp4 in=120

Notice that the in/out points need to be scaled by the speed factor when applied to the timewarp producer.

Brian
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  • how can i speed up only part of video? from 30 to 120 frame for example – user2455079 Sep 16 '16 at 07:34
  • Tried to run: melt "/path/21.mp4" timewarp:2.0:"/path/22.mp4" -mix 7 -mixer luma "/path/25.mp4" -mix 7 -mixer luma Got an error: Failed to load "timewarp:2.0/path/22.mp4" What i did wrong? – user2455079 Jan 25 '17 at 05:12
  • Also tried: melt 2.0:Finish.mov -profile atsc_720p_2997 -consumer avformat:"Out.mp4" it shows no error, but video speed is the same – user2455079 Jan 25 '17 at 05:19
  • timewarp:2.0:file.mp4 - produces just white screen... melt 21.mp4 in=0 out=15 "timewarp:2.0:21.mp4" in=15 out=45 21.mp4 in=45 -consumer avformat:"out.mp4" vcodec=libx264 vb=5500k ab=128k strict=-2 Produced video: https://www.dropbox.com/s/7o6t965qcvy9tuz/out2.mp4?dl=0 – user2455079 Nov 12 '19 at 05:16