This patch demonstrates a simple way to play a movie in Jitter.
Whenever a movie is read into jit.qt.movie, it sends out a read message that reports whether the movie was read in successfully. You can use that information to trigger a getmoviedim message to jit.qt.movie, and use the moviedim to set the dim of jit.qt.movie and all other objects that need to know that information.
This is a program for random editing of a video by periodically leaping to randomly-chosen times in the video and playing from there. The jit.qt.movie object here has its attributes initialized such that: a) it will adapt the dimensions of its matrix based on the dimensions of the movie that is read in, b) it will not automatically start, c) it will not loop, and d) it will only send out new frames of video without repeating a frame.