вт, 2 дек. 2025 г., 10:39 Andrew Randrianasulu <[email protected]>:
> > > вт, 2 дек. 2025 г., 10:00 Luca Marchiori via ffmpeg-user < > [email protected]>: > >> Hi. >> Thanks for your kindly reply! >> Reencoding was my clue but I'm not skilled on video matters. >> When I need to speedup a video (32x or more), the resulting vid is a temp >> one so I would don't care about its size, encoding and other things. It >> will be immediately trashed after viewed. >> Really thing I need is to have a faster video speedup process. >> Is there a lighter (processing time speaking) output format/codec? Again: >> I dont'care about size, a 1hr vid could be a 50GB one too 😊 >> I don't know if this example could be ok but I try: >> JPG(encoded)->BMP(raw, not encoded) as MP4->... >> Thanks for your help!!! >> L >> > > There is example in "man ffmpeg-filters": > > ffmpeg -skip_frame nokey -i file -vsync 0 rest_of_the_params .... > > it should skip all non-keyframes and produce much shorter video, but its > speed up will be determinated by all frames/num_of_keyframes ratio, can be > 50, can be 250 :( > slightly down the road there is "select" filter examples: Select one frame every 100: select='not(mod(n\,100))' Create a mosaic of the first scenes: ffmpeg -i video.avi -vf select='gt(scene\,0.4)' [...] So may be you can replace 100 with speedup_factor in first example? For fastest x264 encode I saw additional parameters set like: ffmpeg -i input.mp4 \ # input file -c:v libx264 \ # H264 encoder -profile:v main \ # H264 profile -g 1 \ # Eliminate P frames -crf 9 \ # The "quality" of the output (7-11 is a good range; lower is better) -bf 0 \ # Eliminate B frames -vendor apl0 \ # Tricks Apple programs output.mp4 https://ericswpark.com/blog/2023/2023-08-07-smooth-scrubbing-videos-version-2/ > If vlc can provide fast preview - may be use it for transcoding, too? > > > >> >> -----Messaggio originale----- >> Da: alexandre schenberg via ffmpeg-user <[email protected]> >> Inviato: lunedì 1 dicembre 2025 19:18 >> A: Luca Marchiori via ffmpeg-user <[email protected]> >> Cc: Luca Marchiori <[email protected]>; alexandre schenberg < >> [email protected]> >> Oggetto: [FFmpeg-user] Re: howto speedup (speedup!) ffmpeg? >> >> Hi. I would guess you are ordering ffmpeg to reencode your video, which >> naturally takes some time. >> _______________________________________________ >> ffmpeg-user mailing list -- [email protected] To unsubscribe send >> an email to [email protected] >> >> _______________________________________________ >> ffmpeg-user mailing list -- [email protected] >> To unsubscribe send an email to [email protected] >> > _______________________________________________ ffmpeg-user mailing list -- [email protected] To unsubscribe send an email to [email protected]
