Are there any limit in file size / RAM for big videos?

Help/How To
1

I’m going to work on a big video. 3k resolution (2960x2160). HDR, so it converted it, and I chose the lossless format. 525GB converted file :slight_smile:

I tried to generate the proxy file for it, but it failed (maybe because I tried the hardware encoder - 4090 GPU here). I should try the software version maybe ?

If the proxy creation is working, will Shotcut be fine with this kind of video ? My computer is decent, but not massive (32GB RAM only). Dedicated harddrive for the video (not SSD, but I could move the project folder to one if necessary). Ideally, I would prefer to use the lossless intermediate video, to keep the quality as high as possible.

Or would it be better to cut the video in shorter parts, then reassemble at the end ? Or will it be ok to end it all ?

Thanks if anyone has any advice or recommandation !

2

Hi!
Personally I do not use proxy files, I just limit the preview scale to 540p.
Cutting the video in shorter parts about 10-30 min is recommend.
The GUI RAM consumption is very dependent on how many objects are used in the video.
You can rejoin all the parts later together in a “master” project.
I was able to generate a 18h long 4K video with this technique with 32GB RAM.
If the export fails because of low ram in the GUI you can run the export command (melt) in the command line. There is an existing documentation about this topic available.

3

How are you doing the join in the master project ? You simply export each part in lossless format, then join them in a new project with the actual encoding at export ?

And how are you cutting in parts without losing or duplicating frames ? I want to keep the original frames. Would vidcutter do a frame perfect cut? (That’s the app I used to extract parts without any reencoding).

4

And thanks for answering by the way, always great to have advices from more experienced users :slight_smile:

5

Yes!
Export to a Lossless format for the parts is the best option per definition.
I am always exporting with nvenc_h265 (NVIDIA HW encoder) with the 65% quality setting and I did not see a quality degrading. There must be some small degradation but maybe my eyes on my monitor aren’t good enough to see the difference.

6

In my experience, the LENGTH of the video is not a factor. If you can edit a 5 minute video, you can edit a 2 hour video.

The number of cuts, transitions and tracks in your project make a big difference on RAM and CPU usage. If you find yourself adding a lot of tracks, and your performance is suffering, that might be a reason to break the project down into smaller parts.

7

Personally, No. There’s no limit to what you can do. Basically, the sky is the limit here.

I have several terabytes of 8k videos, yes they obviously lag, but you can work on them with a powerful machine. Although I might see the CPU as the limitation here, better prefer AMD threadripper in these uses. Otherwise you can go as high as 2tb in ram if you can do that…

I believe that whatever your system has, is the limit for shotcut, upgrade your pc, upgrade your performance of shotcut :slightly_smiling_face: