(No, I haven't seen any Ken Burns documentaries (AFAIK), but his name comes up all the time when googling for stuff to do this kind of animation I am talking about here. He probably is known to the Americans on this list?) I have recently toyed with the thought of writing a tool to produce (low (TV) resolution) animations (for writing to VCD or DVD, mainly) from (high resolution) still images. I.e. if you have some multi-megapixel image, with the tool you could produce animations where you zoom in/out, pan the over some straight or curved path, rotate the viewport, etc. Seems like a nice way to put a bit more "life" into your digital image slideshows. (For a simple and small commercial standalone tool that does this (on Windows), check out MovingPicture from Stage Tools, www.stagetools.com. Demo version downloadable.) Would it be better to write this as a GIMP plug-in, or a standalone tool? If written as a GIMP plug-in, it seems natural to use GIMP's Bezier paths to define the path along which the "virtual camera" moves. Lots of code saved there. As a plug-in, it would perhaps most closely resemble the "Easter Egg" plug-ins as it isn't really a filter, doesn't render anything into a new image, nor does is save or load images. Hmm. The "Ken Burns" plug-in would need to associate more data with the path. The path nodes would correspond to keyframes between which the tool would interpolate zooms and camera movements. Each keyframe would have an associated time values and "virtual camera" orientation and size vector. (To be able to zoom or rotate without moving the virtual camera, path nodes might have several associated keyframes.) The plug-in would provide a GUI to define the keyframes and their attributes, and a preview window, but not do the actual rendering of the animation to AVI, MPEG or whatever format itself, just output a "recipe" that would then be used by a separate batch-oriented program to actually render the animation. It should also be possible to load such a saved recipe and continue working on it, of course. One difficult thing is how to handle the fact that it is possible that the user edits the path while the "Ken Burns" plug-in is active and already has fetched its data with gimp_path_get_points(). Should there be some way for plug-ins to register interest in getting callbacks when paths nodes are moved/added/deleted, etc? Other plug-ins for new kinds of functionality might similarily be interested in getting callbacks when selections are modified, etc. Is there currently any way for plug-ins to get asynchronous callbacks for events like these? --tml
