DBMix is a software DJ mixing system for digital audio. DBMix allows a user to output multiple simultaneous audio streams on a single sound device, and to transform/modify each stream independently. There are five main components to DBMix:
Fourier Synthesis Daemon - this is a daemon application that handles adding multiple data streams into a single data stream for output, allowing you to play multiple songs simultaneously with a single soundcard. Each data input stream to the fourier synthesis daemon is refered to as a "channel", because this is the name given to each input to an analog DJ Mixer.
Clients - responsible for creating input to the system, and writing the data to a dbfsd channel. Example generators are xmms, mpg123, and sox.
DBAudiolib - this is the client interface API to dbmix. It provides transparent format conversion and pitch/speed control.
Mixer - the mixer is the user interface to the DBMix system. It allows a single interface to control all input channels. An example of a mixer is the DBMixer application. DBMixer allows the user to mute, change volume, cue, and crossfade inputs
Peripherals - hardware devices that you can use to control aspects of dbmix. See the section on exmixer below for and example.
Features
Output multiple audio channels (up to 8 inputs) using a single sound device
Cueing support using multiple soundcards. (ability to have one sound device used for a master output, and a second sound device for headphones)
Cueing support using a single soundcard.
Supports the standard digital audio format of 16bit signed data at 44.1 KHz
Use of the Open Sound System for sound device control
Session recording to a wav file (controlled by the dbmixer options menu)
A single DJ Mixer style GUI interface for controlling DBMix channels.
Independent channel controls: volume/gain/level, pitch/speed control +/- 10%mute, cue, and pause.
IPC layer to allow the mixer to control the play/pause/stop/etc of dbmix client programs.
Crossfader
Punch buttons (allows you to add in the muted crossfader input. Handy for popping in sound bytes)
Control of master and cue soundcard mixers
Swap master and cue soundcards on the fly
Autofade buttons with fade speed control
L/R Balance control
Clipping notification
The mixer is optionally controled by an external device. See section titled Exmixer.
Digital Sampler with start/end editing abilities, and Load/Save samples
Beat matching synchronization tools (sorry no UI yet)
Multiple client support: xmms output plugin, mpg123, dbcat, terminatorX, gqmpeg (Note: to use gqmpeg, openthe preferences dialog, choose the Output tab, and enter "-s" in the User options field to enable output to stdout. To launch gqmpeg, type "gqmpeg | dbcat &" at the command prompt)
