Hi
In short--If you add an image/video to the overlay track it should have the same aspect ratio as the main video. If not then you will be left with borders where the main video will be visible.
This assuming you have placed your overlay in the centre and enlarged to full size. There will be no borders if the overlay has the same aspect as the main video and no distortion either.
If the overlay has a different aspect then there will be parts of the background video visible, but, again, your overlay will not stretched or distorted. You can change the aspect of the overlay so it matches your video in two ways. Both involve cropping (or zooming)
Click the overlay so it appears in the left preview pane and add a crop effect, setting the option to 16:9 (if thats the video ratio of you main video); setting the overlay central and using the size slider to make the overlay as large as it will go. It will expand to either reach from side to side or from top to bottom depending on the aspect ratio.Now move the red rectange in the crop window up or down to set it where you want. You will lose some of the overlay top or bottom or both depending where you set it. If the overlay is actually smaller then it may be also expanded to fit the frame with the size adjustment
The other way is using the "none" option and then dragging the borders of the red rectangle out until the overlay just covers the video. (as seen in the right hand preview window).Inevitably you will lose some of the imagery in the overlay but it won't deform it (It may enlarge it).
Setting the chroma key values will not deform the overlay either.
So Unless I am missing something I cant see how you are getting your overlay deformed. I have tried all sorts of ratios and image sizes with no problems
Nat
