Long export time

Help/How To
1

I prepare recorded classes and other videos for posting. My task is straightforward and simple, but the export to mp4 (YouTube/1280x720) typically takes longer than the length of the original mp4.

Today is longer than usual, I’m doing a 2 hour video and it is taking over 4 hours to export. Is that normal? Or maybe it’s a function of my laptop configuration?

The editing I do includes adding a 6 second intro video (3mb), a reduce size logo for the length of the video itself, and a 15 second text filter as a date stamp (three tracks). The logo is a 500kb png reduced to 25% and positioned in the upper left corner.

I realize this is a minor issue compared to some of the “Similar” topics provided, but I’m wondering if there’s something I can do to speed it up. I’m a total video novice so maybe there are some changes I can make that will help.

I’m using a Dell XPS 13 2-in-1 9310 running Win11, 11th Generation Intel(R) Core™ i7-1165G7 Processor (12MB Cache, up to 4.7 GHz), Intel(R) Iris Xe Graphics, 16GB 4267MHz LPDDR4x Memory Onboard.

Thanks,

  • Jeff
2

This means the compositor is being used for the entire video to merge tracks. It’s like processing two videos (tracks) instead of just one. Export time will take longer than the original video partly because it’s twice as much video being processed. Even though the logo is tiny, the alpha channel for the entire frame still has to be processed to mark the non-logo area as see-through.

Having said that, the compositor is probably not the slowest link in the chain. If speed is the goal, go to the Advanced > Other tab on the Export panel, and add preset=veryfast to the list of lines. The quality difference will probably not be noticeable, but the speed difference could be significant.

3

Good information! Thanks. As it happens I’m just ready to export a 1-hour job right now, so I’ll be able to see how the speed-up option does. The double-track issue makes sense. Patience is easier when you know why you’re waiting.

Thanks Austin!

  • Jeff
4

Sadly, no change. I exported a 1:23 video using setup=veryfast and it took 1:43, which is about what I’m used to.

When I went in to Advanced > Other, there was already a line, “setup=fast”. I removed that and added veryfast. Should I have left the other in?

In any case, thanks for the info. Now I know why it is what it is.

  • Jeff
5

That is an unknown option. He wrote “preset”. There should be only one.

6

At first I thought it must have been a typo in my posting, but I went back to that project and it says “preset=fast”. I think you must be right, that my typo was in the project AND the posting.

I really appreciate the catch and letting me know. I will check out “preset=veryfast” on the next video I do.

Jeff

7

So many things affect export time, some of which have been mentioned above. Two others I’d like to add are whether you’re exporting using hardware or software encoding, and whether you have GPU effects enabled in your Shotcut settings.

Hardware encoding is typically much faster than software, not just because dedicated hardware is faster but also because it means the CPU only has to do one processing-intensive task (all the stuff involved in taking your source files and mashing them together to make a video) instead of two (that, plus compressing the video). I haven’t looked up your GPU’s specs, but it would surely support acceleration for AVC and HEVC; it probably doesn’t accelerate AV1. If you’re not using hardware encoding, it’s worth trying. One word of warning: GPU hardware encoders are typically optimized for speed, not compression ratio, so at a comparable visual quality they’ll usually produce larger files.

As for GPU effects, well, like you I’m using my CPU’s built-in GPU, which is weak as GPUs go, and I’ve found that exporting a GPU-enabled project from Shotcut is significantly slower than exporting a non-GPU-enabled project. For a typically project I would do, non-GPU typically exports faster than real time. A 10-minute project might take 5-7 minutes to export. If I enable GPU effects, make a similar project, and export it, it exports at about half real time, so that project would take more like 20 minutes to export*.

Hmm … one other thing based on what you and Austin wrote. If these videos are to be uploaded to Youtube, do you need the logo to be part of the video itself? Youtube lets you customize your channel with a logo that can optionally be superimposed throughout the entire video. I don’t believe you get to choose the size or position, and it applies to all videos on your channel, so it may not work for you, but if you can live with the way Youtube does logos, that could eliminate that one track.

*: You and I have different hardware and our projects are different, so I mention the speeds I get not as a comparison to yours but as a comparison against each other, to show that different settings on identical hardware with similar projects can make a big difference. As they say, your mileage may vary.

1 Like
8

I’m getting a real education here. I’m incorporating all this info into my own notes so that I can try it out and see what results I get. As it happens, the teacher I’m doing this work for has just left on some travels, so it may be a while before I get more to do, but every little bit I learn helps.

Thanks for maintaining an excellent forum, all of you.
Jeff

1 Like
9

In addition to the other suggestions, you might try enabling the “Parallel Processing” option in the advanced export panel.

1 Like
10

Thanks Brian. That goes in my notes as well.

Jeff

11

I do (twice a week) Church services about 1hr-1¼hr long - merging 2 camera .MTS files. On a DELL i5 (I think 6th Gen?) takes 3, maybe 4 hours to render depending on how much I’ve edited it - particularly keyframes.

It’s a little quicker on my ASUS i6 10th Gen, but I’m usually using it for other things.

But I always do a full restart of the computer before rendering - and check TASK MANAGER to see if something (like a browser) isn’t running.

12

Well, the end result of the advice I received is very satisfying. I had a 1:35:00 video that exported in about 1:25:00. That’s pretty much what I was hoping for. So THANKS everyone. And thanks for Shotcut. It’s a good app.

Jeff

1 Like
13

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