NTCCRT: A concurrent constraint framework for real-time interaction (extended version)

Writing multimedia interaction systems is not easy. Their concurrent processes usually access shared resources in a non-deterministic order, often leading to unpredictable behavior. Using Pure Data (Pd) and Max/MSP is possible to program concurrency, however, it is difficult to synchronize processes based on multiple criteria. Process calculi such as the Non-deterministic Timed Concurrent Constraint (ntcc) calculus, overcome that problem by representing multiple criteria as constraints. We propose using our framework Ntccrt to manage concurrency in Pd and Max. Ntccrt is a real-time capable inter- preter for ntcc. Using Ntccrt externals (binary plugins) in Pd we ran models for machine improvisation and signal processing.