trimmed and Exported iMovie stuttering and choppy?
Discussion
Any iMovie experts out there? I have a long video of my granddaughter doing a dance at her dance school and want to trim it to just her 3 minute dance. It came as a 1080p MP4. Loaded it into iMovie and managed to trim it to the required part and exported it. problem is the clip is playing the video element very choppy and jerky. Audio is fine.
Both the exported clip and the trimmed clip in iMovie do this. Is there something I'm not doing please? I'm a movie with the program but never seen this before.
Quick Google suggests running the exported clip through handbrake but I'm hoping I can avoid an extra step and download!
Mac Studio base model M1 Max, 32gig RAM, plenty storage space, latest MacOS 15.2
Both the exported clip and the trimmed clip in iMovie do this. Is there something I'm not doing please? I'm a movie with the program but never seen this before.
Quick Google suggests running the exported clip through handbrake but I'm hoping I can avoid an extra step and download!
Mac Studio base model M1 Max, 32gig RAM, plenty storage space, latest MacOS 15.2
I'm not an imovie expert, but have been an editor / head of post prod
some detective work:
- since the original AND the exported clip play jerky, the issue shouldn't be imovie or the export settings
- Your mac is relatively new and powerful, its not the computer itself thats the issue either.
Some ideas from me;
- Try playing back the video clip in another program, like quicktime player. Does it play back jerky there too? Quicktime is also able to trim clips (menu bar, Edit - Trim) and export them
- While its open in quicktime player press the command and i key together, this will bring up the inspector. click on the video details section - there it will tell you the frame rate (FPS) it was recorded it. Be good to know - if the file is, say 30 fps, but imovie is set to 24fps, then that could cause jerky looking video
- Where is the video clip? If its on an old, slow, external hard drive, that could be the cause.
- Is everything up to date in your mac? latest OS, all software updates done? Some newer video codecs dont play well on older software / operating systems
hope some of that helps!
Fordo said:
I'm not an imovie expert, but have been an editor / head of post prod
some detective work:
- since the original AND the exported clip play jerky, the issue shouldn't be imovie or the export settings
- Your mac is relatively new and powerful, its not the computer itself thats the issue either.
Some ideas from me;
- Try playing back the video clip in another program, like quicktime player. Does it play back jerky there too? Quicktime is also able to trim clips (menu bar, Edit - Trim) and export them
- While its open in quicktime player press the command and i key together, this will bring up the inspector. click on the video details section - there it will tell you the frame rate (FPS) it was recorded it. Be good to know - if the file is, say 30 fps, but imovie is set to 24fps, then that could cause jerky looking video
- Where is the video clip? If its on an old, slow, external hard drive, that could be the cause.
- Is everything up to date in your mac? latest OS, all software updates done? Some newer video codecs dont play well on older software / operating systems
hope some of that helps!
That’s a great help thank you! some detective work:
- since the original AND the exported clip play jerky, the issue shouldn't be imovie or the export settings
- Your mac is relatively new and powerful, its not the computer itself thats the issue either.
Some ideas from me;
- Try playing back the video clip in another program, like quicktime player. Does it play back jerky there too? Quicktime is also able to trim clips (menu bar, Edit - Trim) and export them
- While its open in quicktime player press the command and i key together, this will bring up the inspector. click on the video details section - there it will tell you the frame rate (FPS) it was recorded it. Be good to know - if the file is, say 30 fps, but imovie is set to 24fps, then that could cause jerky looking video
- Where is the video clip? If its on an old, slow, external hard drive, that could be the cause.
- Is everything up to date in your mac? latest OS, all software updates done? Some newer video codecs dont play well on older software / operating systems
hope some of that helps!
I will try doing it in QuickTime just for simplicity, I didn’t realise QT could do that, cheers.
I do all photo editing from a Sandisk extreme pro SSD, it’s super quick but maybe not quick enough for video editing? I’ll try doing it off the internal Mac hard drive and see if that makes a difference.
I’m busy emptying out the iMovie library in case that makes a difference (I doubt it but I was a YouTube thing)
All software is up to date, and of course is native Apple so I will assume plays nicely together.
I didn’t know about frame rate I will check that out too.
Just for clarity, the original movie plays fine in iMovie and QT, it goes jerky after trimming, both the export and trimmed piece stutter although the audio is fine.
Really appreciate your help
No problemo!
Your SSD would be plenty fast for regular old HD, so shouldn't be that.
Sounds to me like it could be a frame rate / export issue then. I'm not 100% with how imovie works, but - check the frame rate of the original video file, then make sure your timeline in imovie is set to the same frame rate, then finally check your export settings so the frame rate is the same - so its the same all the way through the process.
Frame rate mis-matches are notorious for causing odd cadence / judder issues. Usually its because a lot of frame rate standards don't easily 'math' into each other. For example, 50fps to 25fps, that ons easy - the program just loses every other frame, and job done. But converting 30fps to 25fps? - that doesnt convert easily. So frames have to be skipped unevenly. Or converting 25fps up to 30 or 29.97? Its got to, unevenly 'make' frames, by blending some, again at uneven internals. All of this sort of stuff can lead to funky judder issues.
Useless factoid of the day: Since the film standard is 24fps, and uk TV standard is 25fps, they take the easy way to convert and just speed up the film by 1fps (and pitch the audio back down slightly so that remains correct). So films on TV, will be very slightly faster in run time, than the theatrical release! Its such a small change that its not really noticeable.
Your SSD would be plenty fast for regular old HD, so shouldn't be that.
Sounds to me like it could be a frame rate / export issue then. I'm not 100% with how imovie works, but - check the frame rate of the original video file, then make sure your timeline in imovie is set to the same frame rate, then finally check your export settings so the frame rate is the same - so its the same all the way through the process.
Frame rate mis-matches are notorious for causing odd cadence / judder issues. Usually its because a lot of frame rate standards don't easily 'math' into each other. For example, 50fps to 25fps, that ons easy - the program just loses every other frame, and job done. But converting 30fps to 25fps? - that doesnt convert easily. So frames have to be skipped unevenly. Or converting 25fps up to 30 or 29.97? Its got to, unevenly 'make' frames, by blending some, again at uneven internals. All of this sort of stuff can lead to funky judder issues.
Useless factoid of the day: Since the film standard is 24fps, and uk TV standard is 25fps, they take the easy way to convert and just speed up the film by 1fps (and pitch the audio back down slightly so that remains correct). So films on TV, will be very slightly faster in run time, than the theatrical release! Its such a small change that its not really noticeable.
Cheers again, it may well be the frame rate at 24fps.... I tried trimming other videos and they worked fine so it's something about that particular video that is causing the issue.
I decided to convert it using Any Video Converter then trimmed it after that - that worked a treat thanks. Granddaughter will never know how much sweat and tears I went through for that!
Appreciate all your advice thanks.
:Beer:
I decided to convert it using Any Video Converter then trimmed it after that - that worked a treat thanks. Granddaughter will never know how much sweat and tears I went through for that!
Appreciate all your advice thanks.
:Beer:
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