Stabilize

This menu item is available from The Project Bin on a clip in the Project Bin or under the Project Menu menu when a clip is selected in the Project Bin.

This feature applies image stabilization algorithms to the clip which can reduce the shakiness of a bit of footage.

Stabilize

Based on the tooltips from this screen and the docs here, this is what all the options mean:

Accuracy

Accuracy of shakiness detection. Should be >= shakiness factor. 1: low (fast processing). 15: high (slow processing). Default: 4. Recommended: 8.

Shakiness

How shaky is the video? And how quick is the camera? 1: little (fast processing). 10: very strong/quick (slow processing). Default = 4. Note: large values may also reduce the accuracy. This is due to the internals of the movement-detection. Typically you don’t need a value greater than 7.

Stepsize

Step size of search process. Region around minimum is scanned with 1 pixel resolution. Default = 6.

Min. contrast

Below this contrast, the field is discarded. Range 0-1. Default = 0.3. You may want to use a smaller value for a really low contrast clip.

Smoothing

Controls the amount of smoothing/stabilization. The larger the value for smoothing, the more camera movements are compensated. The resulting clip has a lower change in camera speed. Technically it is the number of frames for lowpass filtering = (smoothing * 2) + 1.

For example, with a with 25 fps clip, a value of 12 for the smoothing factor means we would smooth over one second - 12 frames behind the current frame + the current frame (1) + 12 frames after the current frame. Default = 10.

Demo of the difference here (top:3, bottom: 30).

Max shift

Maximal number of pixels to translate image. Default = -1. No limit.

Max angle

Maximum angle to rotate in radians. Default = -1, which means no limit.

Crop

Unchecked means the border of the transformed frames contains the pixels from previous frames. Checked = black background. Default = unchecked.

Zoom

Additional zoom during transform. Percentage to zoom > 0 = zoom in, < 0 = zoom out. The zoom specified here is in addition to the optimum zoom calculated by the program when optzoom is checked. Default = 0.

Optimal Zoom

Use optimal zoom (calculated from transforms). Causes video to zoom until 90% of transformations are hidden. Default is checked. Hint: You can further zoom in with the zoom option.

Optimal Zoom

Zoom per frame (used when “Optimal Zoom” = 2)

Sharpen

Sharpen transformed image. Amount of sharpening: 0: no sharpening. Uses filter unsharp with 5x5 matrix. Default = 0.8.

Show fields

0 = draw nothing, 1 or 2 = show fields and transforms. Use 1 or 2 to preview what the process is going to do. Example. Default = 0. Non-zero values of this parameter are not relevant in the Kdenlive implementation - use zero.

Tripod

Reference frame

Example of the effect of running stabilize - transcode from the original author - Georg Martius.

Side by side https://youtu.be/HYE3KAl8RAQ

Deshaked https://youtu.be/c3CEm8bgVQ0

Original https://youtu.be/cRA5H1LYzM4