Title : RAT - A Real-Time Audio Tool
Author: Arvid Staum
e-mail: arvid@opentech.at
web   : http://www.opentech.at/projectsgpl.html



RAT - Real-time Audio Tools
=========================

	"A real-time multitrack audio recording solution"
	

	Being a musician myself, i know about the weaknesses of today's 
	low cost audio recording software.
	Hardware is getting cheaper almost every day, but there are design
	problems that even the most expensive hardware cannot solve.
	
	My goal is to provide a professional recording solution at about
	one quarter of the costs a commercial solution would cause.
	
	By using and providing free software (licensed under GPL) the
	cost for the end-user is limited to what hardware he wants to use.

	My band's first album is to be recorded using rat.


technical overview:
-------------------
	
	The whole project is based on PC hardware.
	A rtLinux-patched linux kernel (2.4) is the software basis for
	the kernel modules that rat consists of.

	In the current state of the project, only one audio card is supported.
	Though the sofware concept is modular, so the lowest-level module
	can easily be exchanged, allowing integration of different audio
	hardware.
	The currently supported card is the EWS88MT by Terratec. It has
	4 stereo ADC/DACs which deliver 8 audio channels in both directions.
	There is also a SPDIF-interface which adds another two channels for
	each direction.
	
	Scalability is an important aspect of the project.
	Realtime Audio Tools should be able to run on low-end hardware as the
	VIA-C3 (this offers pseudo-embedded audio editing) as well as on
	high-end SMP machines.


project goals:
--------------	

	- Provide a well-designed, modular software concept
	- Implement a low-level driver for at least one audio card
	- Implement routing capabilities
	- Implement fast kernel-based Hard-Disk streaming routines
	- Offer an interface to control the router
       (- provide a minimal user interface)


project status:
---------------

	The modular concept was one of the first steps to begin with.
	It features a low-level module (called "driver"), a central control
	module (called "router"), two diskio-modules (read and write) and the
	possibility to add plugins.
	The plugin engine is not yet implemented.
	
	A real-time driver for the ews88mt audio card is ready and running.
	The router is still under heavy development, but core features like
	buffering are already implemented.
	Kernel-based storage access is one of the critical issues of rat.
	Write support is fully implemented, the read module is only a matter
	of time.
	
	The user-space <--> kernel module communication method is also
	implemented. A non-realtime message queue is used to communicate
 	with the router (which itself can directly access other modules'
	functions and memory space).


general:
--------

	The project is maintained and developed by
		Arvid Staub <arvid@opentech.at>
		Opentech EDV Research

	The whole souce code is published under the terms and conditions
	of the GNU General Public License V2 (GPL).


online resources:
-----------------		
	
	http://www.opentech.at/~arvid