/Soundpipe

A lightweight music DSP library.

Primary LanguageCMIT LicenseMIT

Soundpipe

Soundpipe is a lightweight music DSP library written in C. It aims to provide a set of high-quality DSP modules for composers, sound designers, and creative coders.

Soundpipe supports a wide range of synthesis and audio DSP techniques which include:

  • Classic Filter Design (Moog, Butterworth, etc)
  • High-precision and linearly interpolated wavetable oscillators
  • Bandlimited oscillators (square, saw, triangle)
  • FM synthesis
  • Karplus-strong instruments
  • Variable delay lines
  • String resonators
  • Spectral Resynthesis
  • Partitioned Convolution
  • Physical modeling
  • Pitch tracking
  • Distortion
  • Reverberation
  • Samplers / sample playback
  • Padsynth algorithm
  • Beat repeat
  • Paulstretch algorithm
  • FOF and FOG granular synthesis
  • Time-domain pitch shifting

More information on specific Soundpipe modules can be found in the Soundpipe module reference guide.

Features

  • High quality modules ported from Csound and FAUST
  • Sample accurate timing
  • Small codebase
  • Static library
  • Easy to extend
  • Easy to embed

Compilation

By default, Soundpipe needs libsndfile, and a standard build environment. Other modules that use other external libraries will need to be explicitly compiled by modifying config.mk.

If you are using a Mac you can install libsndfile via Homebrew:

$ brew install libsndfile

Alternatively, clone and build from the libsndfile repository.

On Linux, the libsndfile-dev package will need to be installed.

To compile:

make

sudo make install

Examples

To build the examples, go into the examples folder and run "make", which will create files with a .bin extention. To run an example, run "./ex_foo.bin". When an example is run, it will generate a 5 second file called "test.wav".

Tests

Tests in Soundpipe are used to determine whether or not modules behave as expected. Tests write the output of a module to memory, and check the MD5 hash value of the output against the MD5 value of a reference signal.

To build a test file, go into the test folder, and run "make". Then, run "./run.bin", which runs the tests. As the tests are run, an "ok" will appear in the log if a test passes, and a "not ok" will appear if a test fails.

It is possible to hear the output of a particular test if you know the test number. You will need to have sox installed. For example, to hear what test 11 sounds like, run the following commands:

./run.bin render 11

./write_wave.sh 0011.raw

This will generate a file called out.wav.

The testing utility has a few optional arguments. To see all possible arguments, run "./run.bin help".

The Soundpipe Model

Soundpipe is callback driven. Every time Soundpipe needs a frame, it will call upon a single function specified by the user. Soundpipe modules are designed to process a signal one sample at a time. Every module follows the same life cycle:

  1. Create: Memory is allocated for the data struct.
  2. Initialize: Buffers are allocated, and initial variables and constants are set.
  3. Compute: the module takes in inputs (if applicable), and generates a single sample of output.
  4. Destroy: All memory allocated is freed.

Documentation

If you have lua installed on your computer, you can generate the current html documentation for soundpipe by running "make docs". A folder called "docs" will be created. The top page for the documentation is docs/index.html.

Contributing

If you find a bug, please feel free to make a bug report or a pull-request. If you make a pull-request, please make sure that you do so on the develop branch, and not the master branch.

Additionally, if you'd like to contribute by adding more modules to Soundpipe, please see the Style Guide and the Module How-To Guide.