Different frame rate at different sections in one video

Hello everyone, I am a beginner of Shotcut. Already searched in this forum and on internet, but couldn’t find exact answer to my stupid question.
Basically I am making a video, it is reading story. So most part of its video track is just a picture and a small animation after that picture at the end of video. But when I export it as a whole video I found the video file size is very big (audio only takes about 10MB, but file size is 240MB). I am wondering if there is anyway that can make the picture part video in a very low frame rate and for animation part using normal frame rate to get a much smaller size video?
A solution I could think is to create a separate video file just having picture part and export the file with very low frame rate, then use this video file as source of final video file. I tried it and found the lowest frame rate I can have is 8 fps, and the video size reduced to 110MB, still too big I think.
Not sure if there is any better solution. By the way I am using Shotcut v21.12.24.
Thanks for your help and time upfront.
Kind regards

EDIT: I found some posts said using slower speed, but I couldn’t find such item in properties window. Maybe looked at wrong place?

What you are talking is that the file size after export is big, and you want to make it less.

Check out this tutorial on exporting in shotcut:-

You can’t do anything with the editing here, it’s the exporting settings.

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You could try reducing the video quality from the default (55%). Try 45%, if that is OK try 40% …etc.
The image should take very little space on the video file as it does not change in time and only changes are saved from frame to frame.

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Did some testing with a video that only contains a 1920x1080 PNG shown in 60s

(Disabled audio in encoding)

(Video Mode: HD 1080p 30 FPS)

Looks like the hevc is a good choice for a low file size

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Yes the YouTube preset is definitely not good for this. The main cause of the large filesize is that it uses a GOP of 15 rather than 125, which the others use. This means that 1 frame in 15 will be an I-frame, rather than 1 in every 125. It also has only 2 B-frames between I- and P-frames.

So for every 125 frames the YouTube preset will have about 8 times as many I-frames which only do spacial compressioin, not temporal compression, unlike the P- and B-frames. P-frames have most compression, so the 2:3 ratio for B-framesalso adds to the filesize.

Below are some exports of a 24sec 1080p video of a color-cube PNG.

  • YT = YouTube (GOP=15, B-frames=2, default quality=55%)
  • HEVC_GOP-999 = HEVC with GOP=999 (default Quality=45%)
  • HEVC = HEVC (default GOP=125, default Quality=45%)
  • H264_main = H.264 main profile (default GOP=125, default Quality=55%)
  • 125.3 = Default (default GOP=125, default Quality=55%)
  • 15.3 = Default with GOP=15, B-frames=3(default Quality=55%)
  • 15.2 = Default with GOP=15, B-frames=2 (default quality=55%) essentially the same as YT.

For a good explanation of GOP see:


Hi guys, thanks you all about those informative replies.
As you guys mentioned, firstly I tried to reduce my video resolution from FHD to HD since I don’t need such high quality view, and then tried to reduce quality from 55% to 40%, and keep all other params same, the size now is 28MB, really small as I want!
Thanks all your help and time again, I do appreciate that.

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Glad you found something that worked! There is one additional possibility that might allow you to keep FHD resolution and not require any guess-and-test with quality settings. Try the “Slide Deck (HEVC)” preset. If your media player doesn’t support HEVC, there is also “Slide Deck (H.264)” that will be more compatible.

Your project sounds like mostly static pictures and small amounts of video. For all practical purposes, that is a PowerPoint presentation, which is what the Slide Deck export preset was designed to compress very well. It makes changes to reference frames and other settings to get some really good compression on static images while keeping the quality high.

The one modification that might be worth making to that preset is going to Advanced > Audio and changing it to Stereo with AAC audio codec at 128kbps or higher bitrate. “Slide Deck” is designed with Zoom/Webex conference calls in mind, where all the audio sources are mono. Since you have quality audio, you’ll probably be happier switching it back to stereo.

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