FrameStacker

FrameStacker is great for creating star trails, streaky clouds, and interesting sports videos. FrameStacker lets you stack the frames of a video using a wide variety of blend modes. You just choose a movie file, pick a blend mode, and specify how many frames to combine when building each frame of the output movie. For some videos made with the app, visit https://www.youtube.com/playlist?list=PLNoXydjy2lnOMNCnf5PEkaej6eCP9WOS2 . FrameStacker can stack frames with all of the following blend modes. (Note that not all of these blend modes produce interesting results; in general, you'll want to stick with Lighten or Darken. But I included all of them just for the sake of completeness.) Lighten Screen Darken Multiply Overlay Color Dodge Color Burn Soft Light Hard Light Difference Exclusion Hue Saturation Color Luminosity Clear Copy Source In Source Out Source Atop Destination Over Destination In Destination Out Destination Atop XOR Plus Darker Plus Lighter