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kdenlive image clips always wrong size

Hi, this post is relating to a forum post on the kdenlive forums here where I am discussing the issue of image clips. I have prepared an example to illuminate:

If I make an image in gimp the same size as my video dimensions:

And then import the image as a clip into Kdenlive (using the add clip menu or button) then the clip looks fine in the project tree, but in the project and clip monitor, you can see two black bars down the side.

If I, say, add a clip with a circular black on it, the circle you can see that the aspect ratio of my image seems to be maintained while the size seems to be incorrect.

If I force the aspect ratio using the clip properties menu this is the result:

If I make the a larger image clip:

then the clip looks the same at first in kdenlive, but notice that on the left, in the project tree, the spot is smaller (when in gimp it is the same size)

Here is a video clip which VLC reports as being the same size as my image clip and my project:

It  looks totally different, indeed almost the correct size, in my clip/project monitor:

So video is either different to start off with or is treated differently by kdenlive.

Anyway.

If I make my clip wider I seem to make some progress:

The extra width seemed to help – but the hight now seems to be lacking where it was fine before. An aspect ratio issue? I wonder if it is to do with square and non-square pixels?

I am sure, after much messing around I could find a size of image that seems to display correctly in kdenlive (indeed that’s one of the things I have tried in the past) though I am sure all of this will involved a lot of work with actual photos and be a real pain in the backside to achieve. Primarily, I don’t understand WHY this is such a big problem in the first place. It really shouldn’t be!

It FEELS like there is an ugly default setting involved here – for example the second image I made that was larger but still took up the same space and had the same area missing on the monitor in kdenlive, I assume because it had the same aspect ratio. Surely there could have been more sensible for kdenlive to handle the problem? Maybe it could automatically “crop” a little of the top and bottom rather than shrink the image to fit in the space. That is how, for example, digital printing booths deal with the issue of wrong aspect ratio (given that the top and bottom of a photo are usually ripe from cropping anyway).

The only way I have found to achieve this within kdenlive is to zoom in on the photo – but that results in pixelation, so it looks like kdnlive is actually shrinking the image on import as otherwise the zoom should not cause quality loss until it surpassed the size of the original image? Or maybe I am totally wrong. No clue! Will keep this post updated with whatever occurs on the forum.

A photo montage is one of the first things a newbie might try and make, and yet its not exactly simple to get images right.