I have a timelapse footage shot off a moving vessel. With the motion of the ocean, it looks quite bad. I would like to stabilize this video. Unfortunately, there is also some of the vessel structure in the clip, and since it's well defined and stationary in the source footage, it's what the standard clip job vidstab focuses on. There is no way to specify a mask to tell the vid.stab to not look at the whole frame when doing the stabilization. 

In "Misc" under effects, there is a deshake filter. 
When I apply it to normal shaky footage, it does not stabilize it at all. 
This filter does have the ability to apply a mask, though. It's a bit fiddly, as there is no visual indication of what you are doing, and also the sliders are supposed to have more values than just -1 and 0. 

Finally, dragging the sliders crashes kdenlive UI completely. 

I am assuming that this filter is the FFMPEG deshake filter, as outlined here:
https://ffmpeg.org/ffmpeg-filters.htmlm under section 9.33. The reason for this assumption is that the slider bars have the same titles... 

Reproducible: Always

Steps to Reproduce:
1.Apply effect "deshake" under Misc effects
2.Render video

Actual Results:  
Output video is not deshaked at all, not even a little bit. 
Dragging the sliders mostly just crashes the UI. 


Expected Results:  
Some attempt as video stabilization to be made. 
When dragging the sliders, some rectangle to appear on the video to show the are that the motion estimation is bound to. 

This is on 4k footage in a FullHD project, not sure if that makes any difference.