Quartz Composer is part of the Apple dev tools, and comes with Xcode. You can create modular video patches which are hardware-accelerated on suitable OSX hardware. This is of interest to VJs and live video performance artists.
QC is also quite limited in many regards, and is intended to be one tool among many for development use. These limits and ongoing restrictions for security purposes have frustrated many users.
I really want to use a video buffer in my patches, so I'm going to do up a skeletal Xcode project that incorporates a QC patch, but uses Objective-C to do the video buffering. I'd like an arbitrarily large (resizable) buffer with multiple playback points.
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