Lossless cuts in shotcut

Is it possible to create lossless cuts using shotcut? There is an app I stumbled upon that does this by using ffmpeg, so since shotcut spins ffmpeg underneath I was wondering if it’s possible to have the same functionality? I am used to shotcuts interface so I’d ideally would not switch but this is much sought after function.

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Sorry, reduntant topic. I see this has been adressed in the FAQ

“How do I cut or trim a clip without encoding or transcoding it?
This is not supported, and there are currently no plans to support it. We recommend that you use VirtualDub or Avidemux for that”

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Hi,

Don’t know whether this is too late for you but I’ve been working on a utility to export the cuts (lossless) from a playlist. The tool takes the projects MLT file as it’s input.

It currently has to be the playlist and NOT the timeline.

It uses ffmpeg under the hood with the ‘copy’ codec. It can’t do an exact cut as ffmpeg rounds the start down to the nearest key frame and rounds up to the nearest key frame for the length. It has to do this to stay lossless without reencoding.

I fill the playlist with crude cuts. I then losslessly chop these up to upload to a stock footage website. That’s my use case, maybe it’s not the same as yours.

I also do a lot of drone filming and press record as soon as I take off. At 4k this is a lot of footage to archive. I use this tool to cut all the waste out before archiving without any loss of quality.

Did you see that Extract Sub-clip has been added to the clip Properties menu in v18.09? It is basically the same approach: ffmpeg -i input -ss __ -to __ -c copy -y output. However, people already complain about it not working correctly, and I have to explain your mileage may vary - not only for accuracy but also some formats do not work well. I will probably add a warning dialog. Please share your script to give me a leg up on adding the code to a Playlist menu item, and I will have the same warning dialog.

Hello dale, is your utility available anywhere?

Unfortunately VirtualDub is no longer maintained, and Avidemux doesn’t support most combinations of audio, and can’t add a separate audio track.

I’m not a video app developer, but I would think it should be relatively easy to just not process a track, and only pass it through. Have a “null” filter for it. But again, I don’t know anything about the Shotcut codebase so maybe this is impossible.