I'm working on a project where I want to defish the aerial footage I've shot with a GoPro HD Hero 3 Black Edition. In principle, this is easy, as all I need to do is applying the defish effect to my clips. The problem now is that Kdenlive often loads the project file in a way that albeit the defish parameters are shown correctly, the effect is applied with obviously broken parameters. For instance, I set the defish parameter to 750, and Kdenlive shows this parameter value after loading my project. However, the effect shown on the project monitor looks completely different. I just need to increase the parameter by one, and the effect pops back to normal result.

But what is worse: albeit the preview in the project monitor is correct, Kdenlive or rather MLT render the defish effect always with broken parameters. This makes MLT unusable.

My installation: Kdenlive from sunab svn repo;
frei0r 1.4.0+git20131020.10d8360f-0ubuntu0~sunab~saucy1
kdenlive 0.9.7+git20140202.645eed7a-0ubuntu0~sunab~saucy1
mlt 0.9.1+git20140207.4945fd34-0ubuntu0~sunab~saucy1

http://www.kdenlive.org/mantis/view.php?id=3218

Okay so I found this old post of mine. As I had recently to defish a project, I gave my recent setup a try ... and it went okay: no more parameter mess, no more garbled frames or crashing MLT.

Current MLT is 0.9.9 (from git master), Kdenlive is 15.12.0 (actually 15.13 from git master).

Oh, those were the time...

Apropos: defishing a GoPro image shot in 2.7K I used these defish effect settings:

Amount: 670 (your mileage may vary, but you get a sensible ballpark number to start from)
Type: Equidistant
Scaling: Fill
Manual Scale: 500
Interpolator: Bicubic sharp (yess, for what else do I need an i7?!)
Aspect Type: Square
Manual Aspect: 500