How to disable preview etc. when exporting

[yannsalmon]

I have a project that I cannot render because the GPU gets out of memory. This is largely due to the fact that Shotcut itself uses quite a lot of GPU memory, I assume to allow for editing.

I have tried to reduce this footprint by using scaled preview (360p) and proxies (however, there is not enough GPU memory to generate the proxies either).

Currently, my workflow for rendering this project is to run Export in Shotcut, have the task fail because of OOM, save the task’s XML to a temporary file, close Shotcut, and, having previously done ShotCut.AppImage --appimage-extract to unbundle the binary files, run melt on the saved XML file in a terminal.

While this seems to work (rendering right now), this is a bit cumbersome, and it would be more convenient to be able to have ShotCut unload from memory everything that is not needed when rendering, even if that would make editing while rendering impossible.

How can I do that ?

[brian]

Can you tell us how much memory your system has?

When you run an export in Shotcut, have you tried to close absolutely all other applications on your system?

There are some helpful tips here:

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: …

Also, when you are exporting in Shotcut, you can simply close the project and have no projects open in Shotcut.

[shotcut]

Export at the Command Line

Introduction It is fairly easy to run an export on the command line because Shotcut essentially does the same thing. For example, do an export in the UI and then View > Application > Log… and scroll to the end. You will see the command line printed; however, the file name is fully encoded to workaround potential character set problems. Quick Start The general basic form is: LC_ALL=C melt project.mlt -consumer avformat:export.mp4 Of course, you substitute your own file names possibly with a pa…

[yannsalmon]

The GPU has 4GB of memory. The biggest memory consumer is, by far, ShotCut. Next comes the window manager (kwin_x11). I had suspected Firefox of hogging memory, but while it does use vast amounts of general RAM, its GPU memory consumption is very low.

Closing all other applications would therefore not change much, and is not really an option, since I do not intend to do nothing with my computer while it is rendering.

Fortunately, my project has a static image for 4 seconds at the beginning, and if I open the project in Shotcut and remain in this timeframe, it does not do something with the big video clip that comes next and therefore does not consume the abovementionned swathes of GPU memory.

More generally (but this might warrant another topic), having a big video clip in the project also causes the Shotcut GUI to be very irresponsive, even for mundane things like zooming the timeline in or out (not the preview, mind you, the thing that symbolically displays where clips go). This is very dumbfounding because besides redrawing a smaller or bigger waveform for the audio track, there is not much to do with the sources on this occasion.

Anyway, kdenlive does not show this irresponsiveness or abundant memory consumption (I can even fiddle with a project while another one is rendering !), which, despite some points like rendering presets where Shotcut is superior to it, let me finish what I had to do.