Many digital cameras generate MJPEG files when capturing video. Unfortunately MJPEG files require a lot of space as they do not make use of any video compression techniques (approximately 5x the size of a MPEG-4 file).

MJPEG Converter is a tool that scans a directory (incl. its subdirectories) for MJPEG files and converts them to MPEG-4 (H.264 with AAC). You can either scan your whole photo/video library or the memory card of the camera before transferring the files to the PC.