py_headless_daw

A GUI-less DAW (Digital Audio Workstation) for producing electronic music using python

Links to detailed documentation

Here are links to more in-depth docs on several aspects of the system:

• Reference producer implementation
  • an example of a "producer" that generates random "songs". This is meant to be a reference for "real" producers' implementations.
• Drum synth
• Readme for "Riding on Bugs" demo project

Main concepts

To create some audio with this library, the 3-step workflow described below is to be followed. Each step of the workflow uses the output artifact produced by the previous one:

• Step 1: create a project
  • output: an instance of Project class
• Step 2: compile a project
  • output: a pair of so called "output stream nodes"
• Step 3: render audio
  • output: a wave file

Below go more detailed descriptions of concepts related to each step of the workflow.

Demo project

There is a demo project that can be used as a reference. Find its more dertailed readme here:

Readme for "Riding on Bugs" demo project

Create a Project

A project (an instance of Project class), is, essentially, a group of interconnected tracks (Track class)

Among tracks, one is special: the "master". This is the track that project object refers to, the rest of the tracks can be discovered through track connections.

Basically, the set of tracks is a bi-directional graph where every track knows its inputs and outputs.

Apart from inputs and outputs, each track has a chain of "plugins" used to modify data prior to passing it to the track's outputs.

Types Of Tracks

Midi Track

A track that produces midi data. Midi data is stored in MidiClip instances. Importantly, MidiTrack can only be connected to an AudioTrack whose plugin chain has a synth as the first plugin.

Audio Track

A track that takes its inputs, applies some processing to it (using plugins) and outputs audio to downstream tracks.

Sampler Track

A special case of audio track that has no inputs (it does not expect any track to feed audio into it). Instead, it maintains the list of AudioClip instances that are used to produce the data to feed into the head of its plugin chain. In any other respect, SamplerTrack is like any other AudioTrack

Compile a Project

On a lower level, the sound-producing structure consists of interconnected units:

Every unit is comprised of:

• a number of input nodes
• a number of output nodes
• a processing strategy that knows how to use data taken from input nodes to produce output data to be sent to output ndoes

There are two types of nodes:

• stream nodes, each representing a single channel of audio (e.g. "left")
• event nodes, each representing a stream of events

Units can be interconnected to produce multi-stage processing. For that, connectors are used.

Compiling a project

Compilation of a project is turning a project instance into a list of StreamNode instances. After successful compilation, it is possible to render stream data from these nodes to produce the resulting master.