![]() The ability to manipulate video so easily, without a UI, also makes for easy automation of media, especially when you combine this technique with clipping video - you get just the frames you want at the speed you want. ![]() I'm using following command: ffmpeg -framerate 60 -startnumber 13 -i image00204d.png -r 60 -vcodec png out.mov I've captured image sequence at 60fps in mind however even with setting -framerate 60 before inputs does not output 60fps video at least not visually. I recently used this slow-mo technique on a highlights video downloaded from YouTube to draw my own conclusions about a specific play. Hello, I'm having issue creating 60fps video from image sequence. doubling speed seems to require a different multiple. More confusing is that the atempo setting seems to require reverse logic to setpts i.e. loop over frames from the video file stream while fvs.more (): grab the frame from the threaded video file stream, resize it, and convert it to grayscale (while still retaining 3 channels) frame fvs.read () frame imutils.resize (frame, width450) frame cv2.cvtcolor (frame, cv2.colorbgr2gray) frame np. If you care to sync the audio speed with the video speed, things get a bit more complicated: ffmpeg -i input.mp4 -filter_complex "setpts=0.5*PTS atempo=2.0" -map "" -map "" output.mp4 If you use a larger value, the video will display in slower motion. The lower the PTS value, the faster the time-lapse video is generated. A fps of 5 indicates a frame duration of 200 ms whereas a fps of 90 indicates a frame duration of 11 ms (after rounding). ![]() It's more helpful to think of this in terms of frame duration rather than fps, since that is what setpts can directly alter. It turns out all you need to do is pass in filter with a PTS ( presentation timestamp) value: Faster Video Speed ffmpeg -i input.mp4 -filter:v "setpts=0.5*PTS" output.mp4 Slower Video Speed ffmpeg -i input.mp4 -filter:v "setpts=2*PTS" output.mp4 1 Answer Sorted by: 3 You can use the setpts filter to gradually change fps. One of my favorite TV sports illustration techniques is speeding video up (time-lapse) or slowing it way down (slo-mo replay) naturally I wanted to know how to manipulate video speed with ffmpeg. I don't have their advanced TV software or hardware, of course, but I do have a love for ffmpeg, which allows me to do everything from clip videos to change video formats, create tacky highlight videos with emo techno music combine audio and video, and more. I watch a lot of sports and recently I've become fascinated with some of the methodologies they use to illustrate events within the game.
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