Des architectures logicielles particulières sont nécessaires au domaine de l'informatique musicale. Outre qu?elles permettent le partage des ressources critiques de la machine entre plusieurs applications, elles conditionnent très fortement leurs activités de communication et de collaboration. Après un bref rappel sur les carences des systèmes d?exploitation relativement aux besoins des applications musicales, nous présenterons MidiShare, une architecture qui l... Lire la suite

Des architectures logicielles particulières sont nécessaires au domaine de l'informatique musicale. Outre qu?elles permettent le partage des ressources critiques de la machine entre plusieurs applications, elles conditionnent très fortement leurs activités de communication et de collaboration. Après un bref rappel sur les carences des systèmes d?exploitation relativement aux besoins des applications musicales, nous présenterons MidiShare, une architecture qui leur est dédiée, en insistant sur la prise en compte particulière du temps et de la communication. Nous montrerons ensuite que la souplesse du modèle de communication adopté permet son extension aux réseaux locaux avec l?exemple d?une implémentation pour Ethernet. Enfin, nous présenterons les perspectives de l?organisation de la collaboration entre les applications.

We propose a way to transmit real-time musical data flow on Ethernet. The presented implementation is based on the software archi-tecture of MidiShare. After some reminders about Ethernet and MidiShare, we shall present an overview of the intended solution. Then we shall examine the chosen protocols, the implementa-tion and its performance.

This article presents an approach in the design of music programming languages based on Lambda Calculus. It shows, through several examples, that a purely descriptive language, that is to say a language without any programming capability, can be equipped with programming capabilities by the addition of a limited number of simple constructs.

Real time interapplication communications are a key feature in musical multi-task operating systems. Independent applications can therefore be connected and collaborate by exchanging messages and data through communication channels. All these collaborating applications define a virtual network the user can dynamically configurate. The topology of such virtual network specifies the way applications can be connected together. This paper introduces a new hierarchi... Lire la suite

Real time interapplication communications are a key feature in musical multi-task operating systems. Independent applications can therefore be connected and collaborate by exchanging messages and data through communication channels. All these collaborating applications define a virtual network the user can dynamically configurate. The topology of such virtual network specifies the way applications can be connected together. This paper introduces a new hierarchical topology we recently implemented in our MidiShare multi-task operating system. This approach offers several advantages and particularly when a large number of applications are involved or in a multi-user context.

Scheduling problems hold an important place in most real-time musical systems. We here present an algorithm allowing to solve these problems efficiently and ensuring a bounded low scheduling cost per event in any circumstances. Its principle is to maintain events all the better sorted out as their running time gets closer.

This paper introduces MidiShare, a real time software module meant for the development of Midi applications in a multi-tasks context. MidiShare brings facility in most of the fields concerned with the development of musical applications: communications management, precise time control, tasks scheduling. The originality of MidiShare lies in its capacity to deal with multiple Midi applications running at the same time. Besides, MidiShare offers some interesting p... Lire la suite

This paper introduces MidiShare, a real time software module meant for the development of Midi applications in a multi-tasks context. MidiShare brings facility in most of the fields concerned with the development of musical applications: communications management, precise time control, tasks scheduling. The originality of MidiShare lies in its capacity to deal with multiple Midi applications running at the same time. Besides, MidiShare offers some interesting possibilities, particularly the one consisting in a dynamic connection between Midi applications through internal links. MidiShare was at first designed for the Macintosh under MultiFinder, it is now available on other machines.