A new release of gsvideo (0.5.1) that I uploaded today to sourceforge solves a bug in the recenlty added GSMovieMaker, which prevented to write frames to a movie file while playing another movie. This has been solved by including an updated version of gstreamer-java (the underlying bindings that allow Processing to communicate with GStreamer).
Also, a couple of new features/improvements:
- GSPipeline with new implementation that allows to run DV-capture pipelines (tested on Windows only)
- added parameter to set movie quality in GSMovieMaker (although it works only for the Theora codec).