Non-Realtime Recording with Jitter
The cathode ray tube (CRT) emulation I wrote in Jitter for GLG originally ran in realtime. This worked fine for the premiere of the piece, but I wanted to render a self-contained version of the piece (to share online, and to make screening the piece in the future as easy as possible).
I tried recording the output of my Jitter patch into the jit.qt.record object, but I ran into all sorts of problems trying to synchronize the audio with the video in iMovie. I came across the jit.vcr object, which purports to “takes a sequence of Jitter matrices, plus MSP audio, as input, saving the sequence to disk as a synchronized QuickTime movie.” However, I still had problems (it may be under-documented, or the problem may have been on my end). Things seemed dire, and in my darkest moments, I even considered bouncing the finished product down as a Quicktime screen recording.
Luckily, I pulled it together and decided to RTFM. Cycling 74 has really nice tutorial series for how to use Max, MSP, and Jitter, and one of them described exactly how to ameliorate the problems I had. Jitter Tutorial 19: Recording Quicktime Movies describes three ways for recording movies, two “on the clock” and one “off the clock.” Reading this tutorial (and employing the third, “off the clock” method) helped me fix my problem and successfully export my finished video. This tutorial also does a nice job of explaining Jitter’s event-driven behavior, and the various concessions that Jitter makes to make realtime video processing more feasible.