arXiv subjects

Mauricio Toro

Publications and source records attributed to Mauricio Toro.

24 records · Page 2Linked to original sources

arXiv2015

Towards non-threaded Concurrent Constraint Programming for implementing multimedia interaction systems

In this work we explain the implementation of event-driven real-time interpreters for the Concurrent Constraint Programming (CCP) and Non-deterministic Timed Concurrent Constraint (NTCC) for- malisms. The CCP interpreter was tested with a program to find, concurrently, paths in a graph and it will be used in the future to find musical sequences in the music improvisation software Omax, developed by the French Acoustics/Music Research Institute (IRCAM). In the other hand, the NTCC interpreter was tested with a music improvisation system based on NTCC (CCFOMI), developed by the AVISPA research group and IRCAM. Additionally, we present GECOL 2, a wrapper for the Generic Constraints Development Environment (GECODE) to Common LISP, de- veloped to port the interpreters to Common LISP in the future. We concluded that using GECODE for the concurrency control avoids the need of having threads and synchronizing them, leading to a simple and efficient implementation of CCP and NTCC. We also noticed that the time units in NTCC interpreter do not represent discrete time units, because when we simulate the NTCC specifications in the interpreter, the time units have different durations. In the future, we propose forcing the duration of each time unit to a fix time, that way we would be able to reason about NTCC time units as we do with discrete time units.

cs.MM↗

arXiv2015

An Extension of Interactive Scores for Multimedia Scenarios with Temporal Relations for Micro and Macro Controls

Software to design multimedia scenarios is usually based either on a fixed timeline or on cue lists, but both models are unrelated temporally. On the contrary, the formalism of interactive scores can describe multimedia scenarios with flexible and fixed temporal relations among the objects of the scenario, but cannot express neither temporal relations for micro controls nor signal processing. We extend interactive scores with such relations and with sound processing. We show some applications and we describe how they can be implemented in Pure Data. Our implementation has low average relative jitter even under high cpu load.

cs.MM↗

arXiv2015

Gelisp: A Library to Represent Musical CSPs and Search Strategies

In this paper we present Gelisp, a new library to represent musical Constraint Satisfaction Problems and search strategies intuitively. Gelisp has two interfaces, a command-line one for Common Lisp and a graphical one for OpenMusic. Using Gelisp, we solved a problem of automatic music generation proposed by composer Michael Jarrell and we found solutions for the All-interval series.

cs.AI↗

arXiv2015

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.

cs.LO↗

arXiv2015

A Model for Interactive Scores with Temporal Constraints and Conditional Branching

Interactive Scores (IS) are a formalism for the design and performance of interactive multimedia scenarios. IS provide temporal relations (TR), but they cannot represent conditional branching and TRs simultaneously. We propose an extension to Allombert et al.'s IS model by including a condition on the TRs. We found out that in order to have a coherent model in all possible scenarios, durations must be flexible; however, sometimes it is possible to have fixed durations. To show the relevance of our model, we modeled an existing multimedia installation called Mariona. In Mariona there is choice, random durations and loops. Whether we can represent all the TRs available in Allombert et al.'s model into ours, or we have to choose between a timed conditional branching model and a pure temporal model before writing a scenario, still remains as an open question.

cs.LO↗

arXiv2015

Concurrent Constraint Machine Improvisation: Models and Implementation

Machine improvisation creates music either by explicit coding of rules or by applying machine learning methods. We deal with the latter case. An improvisation system capable of real-time must execute two process concurrently: one to apply machine learning methods to musical sequences in order to capture prominent musical features, and one to produce musical sequences stylistically consistent with the learned material. As an example, the Concurrent Constraint Factor Oracle Model for Music Improvisation (ccfomi), based upon Non-deterministic Timed Concurrent Constraint (ntcc) calculus, uses the Factor Oracle to store the learned sequences.

cs.LO↗