Following "Pan and Zoom" in our last release in Kdenlive 0.8 there will be a new GUI for the Corners effect, unleashing its real power:
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Corners was already available in Kdenlive 0.7.8 (under its frei0r name c0rners) but probably remained unrecognized because it was very hard to use. The x, y position of every corner had to be adjusted using a slider. In the next release this should be whole lot easier. The corners can be moved directly on the monitor. Additionally there are some more controls to make your life easier: The red cross in the center of the upper layer moves all corners at once. Using the controls on the edges of the upper layer you can move the two corners next to them.
Let's have a closer look at the interface and some of the parameters:
Despite its power there are some things to consider before enjoying it:
The "c0rners" filter was introduced in frei0r 1.2. However when using keyframes and also when changing multiple parameters it was very, very slow. Additionally the parameter Alpha operation was not available. It is therefore highly recommended to upgrade to frei0r 1.3 (released today, 03/09/11).
You shouldn't use this effect to zoom into media with a resolution higher than the project resolution. If doing so the image will be scaled down first and then scaled up by c0rners afterwards. To avoid this loss use Pan and zoom. It will pass any downscaling. You can then afterwards apply c0rners for some fancy movements.
As you might have already noticed this effect can do much more than placing images inside each other.
I would therefore like to thank Marko for writing this awesome effect!
A quick note at the end: Attaching your video camera on a monopod and holding it upside down just a bit above the ground while riding a bike creates a nice look ;)