Unwanted keyframes are created as I play a video between two pre-existing keyframes

This bug only affects filters that use VUI, such as Text: Simple, Spot Remover, and Crop: Rectangle.

Steps to reproduce:

  1. Launch Shotcut.
  2. Open a video file.
  3. Move a clip to the Timeline.
    This bug still happens even if a filter is applied to Source.
  4. Apply a filter that uses VUI.
    In my test, Text: Simple, Spot Remover, Crop: Rectangle, and Timer filters are affected, but not Size, Position & Rotate and Text: Rich.
  5. Click Use Keyframes for this parameter button to show advanced keyframes area.
  6. Create two keyframes with different positions or sizes.
  7. Place the playhead slightly left of the first keyframe and attempt to play the video between the two keyframes.
  8. A large number of keyframes are created as the playhead pass through the first keyframe. RAM used by Shotcut tends to increase until it’s full.
    Additional notes:
    A. Tested on Windows 10
    B. Tested on two of my PCs that have different CPUs.
    C. Happens only in v21.05.01. v21.03.21 and prior don’t exhibit this bug.
    D. Happens irrespective of video file extensions (tested with mp4 and webm), resolutions (tested 1080p and 720p), or fps (tested 30fps and 60fps).
1 Like

I was able to reproduce the same issue with Text:Simple.

Shotcut Version 21.05.01
Windows 10 Home.
Video Mode: 720p, 60fps

Test #1
Playing clip in the Keyframes window

Green0501.mlt (5.6 KB)
Application Log Green0501.txt (69.6 KB)

Test #2
Did not save MLT project file
Played from Timeline instead of Keyframes.
Still produces unwanted keyframes, playhead goes beyond clip/project duration.

Application Log Green0501 timeline play.txt (62.8 KB)

Also confirmed using Open Other > Color as the clip rather than an actual video file.

Linux Mint 20.1, Shotcut 21.05.01 AppImage

@TRA Excellent bug report, by the way.

Thanks for your report. This has been fixed for the next build.

1 Like

Yeah, it sure is. @TRA is actually the one that inspired me to dedicate time to do bug reports years ago. His numerous detailed bug reports were helping to make a real difference on the development of Shotcut. So I decided to follow his example really. :grinning:

He sadly stopped posting though 3 years ago. I hope his reappearance now isn’t a short one and he’ll be posting regularly again. His contributions are important and really appreciated.