I'm trying to create a progress bar with multiple thumbnails from a video like this one:

Current solution

I have a copy of the main video that I'm seeking to the correct position and then drawing the frame into a canvas.

Problem with the current solution

I have to draw these thumbnails one by one, since I can't seek a video to multiple positions at the same time. I'm wondering if there's a way I can parallelize drawing these thumbnails. The only way I can think of is by having multiple copies of the same video - one for each canvas -, but that'd probably consume a lot of memory and affect performance.

What about fetching pre-selected thumbnails from a server?

I don't have these videos beforehand, they are either recorded in browser or uploaded at the time of trimming.