Video stuttering as if the frame rate is too low

This is something I noticed when viewing my first raw video made by a drone. The frame rate was 30 f/s but the video, when doing horizontal pans, was nauseating to view. I understand that by reducing the shutter rate on the camera will cause motion blur which will help.

The attached video was made by stitching several still phots on Photoshop. The “panoramic” image ended up being 5342x1080. I added this image to ShotCut with the video mode at 1920 x 1080. Much to my delight, I was able to use the Size, Position & Rotate filter along with Key Frames to make a horizontal pan.

The video was encoded at 60 f/s. What I see on playback appears to show a slower framerate making the resulting “video” very hard to watch. (at least on my monitor)

Can someone enlighten me on what I’m looking at. Am I pushing the Key Frame feature beyond its frame rate or is there something else going on?

Please keep in mind that the source was a still image.

Very much so, ideally around 1/50th shutter speed. The camera might need ND filters to avoid blowing out the image.

You’re right. I count 25 distinct frames per second despite the encoding at 60fps. This tells me Shotcut was in Automatic video mode. When a still image (which has no frame rate) is dropped onto the timeline in Automatic mode, the frame rate defaults to 25fps. Exporting a 25fps timeline at 60fps basically means each frame is getting duplicated verbatim in the output. Shotcut is not fabricating in-between frames to make 25fps smoothen into 60fps. To do this right, the video mode needs to be forced to 60fps before the first item is dropped onto the timeline.

Yes to this as well. A general rule of thumb is that an object needs seven seconds in order to smoothly pan from one side of the screen to the other, and this assumes proper motion blur is present. Your video has a tree going edge-to-edge in four seconds. It’s simply too fast. Since the source image does not have any motion blur, pans will need significantly more than seven seconds to avoid a strobing effect. It might help to add a blur filter with a very small amount to soften the edges. More information about panning speed can be found at the RED Learning site:

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While your video is 60 fps, I believe your project was not 60 fps. When I download your video and step frame-by-frame in Shotcut, I see each frame repeated. Changing frame rate in Export > Advanced > Video does not does not change the project

Thank you. Yes, the project was set for 24 f/s. Oops!

When I started a new project with video mode on automatic, the 5342 x 1080 image, set the project to 5342 x 1080, 24 f/s. After realizing that wasn’t going to give me the desired results, I changed the resolution to 1920 x 1080 but forgot to check the frame rate.

It’s interesting that a 5342 x 1080 image in a 1920 x 1080 project resulted in a 1920 x 388 “letter box”. The Size, Position & Rotate filter came to the rescue by zooming the image 278%. Position and Keyframes panned it horizontally to emulate a video clip.

I think it looks pretty cool considering it started out as 4 stills taken with a phone.

Thank you for your help.


Thank you Austin. That’s great information that I haven’t seen demonstrated as well as has done. I suppose, going back a couple of decades, the persistence of the CRT phosphor helped with motion blur to some extent along with displays being much smaller than they are today.

Thanks for your quick replay. I’m going to try the blur filter as you suggested.

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If when viewing a video at 60 fps on a monitor that has a refresh rate of 60Hz, and neither monitor nor player have an external reference, I often wonder if occasional duplicate or missing frames occur.

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