Effects applied as rendered video in the timeline/preview

Hi, I notice that adding several effects like color correction etc slows down the preview playback. Suggestions like proxy editing and scaling to lower resolutions do help. But What if we add features like a paid video editor Cyberlink Power Director has?

What it does in my observation is that, when an effect is added to a video in the timeline, the video in the timeline is replaced with a rendered version with the effects applied such as blur, but only in the preview in the timeline. That way, when we add several effects to the preview, it will play smoothly because the video in the timeline is already rendered with effects as opposed to playing the effects in real-time.

The 2nd thing I noticed is that the said video editor keeps track of the effect applied in the timeline. That way, when the user ‘undo’, ‘redo’, or remove one effect from the 4 effects applied, the video editor will just re-render the video in the timeline with all other effects applied minus the removed effect.

The only caveat is that the user will have to wait for the render to finish before continuing. But the editing will be much more responsive than processing the effects in real-time while the preview is playing. What do you think, is that possible?


One way is to perhaps use the idle cores of a multi-core processor using some of the modern thread libraries.

Mapping of C++ threads to CPU/cores : cpp_questions (reddit.com)

Maybe some commercial products are already doing this. Perhaps it’s just a matter of paying the monthly subscription to get that feature and a faster editor that uses processor cores more effectively

Personally, I’m not finding Shotcut slow in any way. Maybe that is to do with my workflow or the very simple projects that I work on.

At some Conferences a few years ago there were people demonstrating very advanced and fast Video Editing and Realtime stuff from high end nVidia cards. Some people throw hardware at the problem which is cheaper than Programmer time.

Okay, thanks! The Proxy is working fine with me, I’m withdrawing my suggestion.

This idea was previously explored here. It is a great idea and several other editors do it. With infinite time, money, and developer power, it is of course possible. But Apple has more of those things than the Shotcut project does. Also, the following thread explores how complex this idea actually is to implement for anyone interested in trying:

I’m not a project developer and I’m not saying it will never happen. I’m just saying it’s a complex task and this is one reason it hasn’t been implemented yet.

Shotcut doesn’t have this feature, but you can kind of do it your self manually when you need a smooth preview of a certain part of the timeline. It involves the use of a marker.

I made a tutorial about this a few months ago.


I didn’t know it was possible))) Thank you for your instructional video!