How to Reduce Memory Usage

Here are ways to reduce the memory usage in general:

  • Save and restart Shotcut
  • Close other browser tabs.
  • Close other applications.
  • Reboot (does all of the above).

Here are ways to reduce the memory usage of your project:

  • Reduce the resolution of the Video Mode.
  • Reduce the number of tracks. The number of tracks will increase the amount of caching to prevent files from being closed and reopened repeatedly from one frame to the next.

Here are some ways to reduce the memory usage while editing:

  • Make sure Settings > Realtime is turned ON. When it is off, it uses more threads, and more threads needs more memory.
  • Use Preview Scaling and Proxy Editing.

Here are some ways to reduce the memory usage while exporting:

  • See all of the things list above about reducing memory usage in general and of the project.
  • Turn OFF Export > Advanced > Video > Parallel processing. That uses more threads, which needs more memory.
  • Turn ON Export > Use hardware encoder (use Configure… > Detect if needed).
  • It can be very helpful to reboot, start Shotcut and only Shotcut after reboot, open the project but do not play through it, and then export. You are then guaranteed to give the most of your available physical memory to the Shotcut export process.
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On all Linux operating systems you can open a terminal and run this command # “sync; echo 1 > /proc/sys/vm/drop_caches” as administrator with root privalages when Shotcut gives a LOW MEMORY warning. This will safely clear the first level cache and allow Shotcut to continue without have to save your work and close out and re-start Shotcut. On MS Windows PCs you can also attempt to clear your RAM.

Quick question: if I reduce the resolution in video mode to reduce memory usage, can I still export the completed project in HD (1080p)? If so how (I have version 22.12.21)?

Yes, but it will not look HD because it will be rendered at the reduced Video Mode resolution and then scaled up to HD at export. Video Mode defines the render resolution; Export > Video > Resolution defines the encoded resolution after render.

Thanks. I am impressed with the speed of your replies, I was expecting to wait a day before you got to me, considering the popularity of your software.

I have a question related to this issue. So I’m trying to edit a video and I needed a voiceover for it so I tried using the one on shotcut but for some reason there was no video. Anyway I found a way of doing a voiceover using Microsoft Clipchamp but when I tried to put that in shotcut I by mistake put it in the audio timeline instead of the video one (I put it in the video one then detach the audio and then align the audio) so when I did that shotcut crashed. At first I thought I lost all my hard work because I didn’t save the project. But luckily the autosave came in clutch. So after that, when I click retrieving the autosaved project it says shotcut is not responding. I come to find out that it is using 97% of my memory. Since I have 16gb of RAM I thought maybe if I increased it to 32gb it would work. But even after upgrading it still uses 97% of my memory. It comes down to around 40-50% after sometime but by the time that happens, shotcut becomes so unresponsive that I can’t even minimize the screen. Is there anyway I can fix this or save my unsaved project? I am sorry for such a long story btw.

For the autosaved/unsaved project you can manually create a copy of the autosaved file without opening Shotcut by searching for a <random_name>.mlt file in the %appdata% directory (mine is: C:\Users\Daniel\AppData\Local\Meltytech\Shotcut\autosave\315e4dcbb3ebb1f93cf3dbdb1e6da93c.mlt)

For the memory/crash try to temporarrily disable the waveform generation maybe it will help: