Scott,
You don’t say what format you need for your video and I have never worked with video, however, it is easy to create a transparent file in PSE. Go to File>New, type in your dimensions (probably pixel units?) and select the option for Transparent. You would do a File>Save As and scroll for the appropriate format for saving. However, only certain formats respect transparency, jpg is NOT one of them. The file extension .psd supports transparency, as does .tif and I believe .png (and of course .gif).
All images are rectangular, though some parts may be transparent making the image look like a different shape. You could create a new file, put a heart shape on it and have the interior of the heart be transparent for your video "window" but outside the heart’s perimeter would have to be a color or pattern or some such, as you can’t differentiate and delineate the heart shape without some other data in the file. You could also, put a heart shape on a transparent new file, use Edit>Stroke to outline the heart shape and have its interior be transparent. It seems that you would have to restrict your video to exactly the same shape as the heart with this second method though, or else the whole rectangular video data will appear with a heart outline on top of it.
Scott,
Or you could create a new transparent file and create a frame around the exterior and have the interior transparent. As I said though, the file format might be an issue.
After you create the new trans. file, go Select>All, Edit>Stoke (choose inside) (experiment with the width in pixel values). The color of the "frame" will be which ever color appears on the foremost color square at the bottom of the Tool Box. These colors are selectable. Or you could create a picture frame type of dealy (3D ish)around the outside of the trans. file.
