ciseaux

JavaScript utility to chop an audio buffer, inspired from youpy/scissor

✂️ Demo

Ciseaux - JavaScript utility to chop an audio buffer : online examples

✂️ Installation

bower:

bower install ciseaux

npm:

npm install ciseaux

downloads:

• ciseaux.js
• ciseaux.min.js

✂️ API

• Ciseaux.from(src: ArrayBuffer|string, [audioContext: AudioContext]): Promise<Tape>
• Ciseaux.silence(duration: number): Tape
• Ciseaux.concat(...tapes: Tape): Tape
• Ciseaux.mix(...tapes: Tape, [method='silence']): Tape

Ciseaux.Tape

• constructor(audioBuffer: AudioBuffer)

Instance attributes

• sampleRate: number readonly
• length: number readonly
• duration: number readonly
• numberOfChannels readonly
• numberOfTracks readonly

Instance methods

• gain(gain: number = 1): Tape
• pan(pan: number = 0): Tape
• reverse(): Tape
• pitch(rate: number = 1): Tape
• stretch(rate: number = 1): Tape
  • not implemented (Pull Request please)
• concat(...tapes: Tape): Tape
• slice(startTime: number = 0, duration: number = inf): Tape
• loop(n: number = 2): Tape
• fill(duration: number): Tape
• replace(startTime: number = 0, duration: number = 0, tape: Tape = null): Tape
• split(n: number = 2): Tape[]
• mix(...tapes: Tape, [method = 'silence']): Tape
• render(audioContext: AudioContext): Promise<AudioBuffer>
• dispose(): void

Ciseaux.Sequence

Utility class for creating a sequence tape that is concatenated tapes

• constructor(...args: any)
  • pattern: string
  • durationPerStep: number|number[]
  • instruments: object

Instance methods

• apply(...args: any): Tape
  • pattern: string
  • durationPerStep: number|number[]
  • instruments: object

✂️ Usage

tape = new Ciseaux.Tape(audioBuffer);

tape = Ciseaux.concat([ tape.slice(10, 1), tape.slice(2, 3) ]).loop(4);

tape.render(audioContext).then(function(audioBuffer) {
  var bufSrc = audioContext.createBuffer();

  bufSrc.buffer = audioBuffer;
  bufSrc.start(audioContext.currentTime);
  bufSrc.connect();
});

✂️ Examples

slice + concat

tape = tape2.slice(0, 1.5).concat(tape3.slice(0, 0.5), tape1.slice(-2));

slice + concat + loop

tape = tape3.slice(0, 0.5).concat(Ciseaux.silence(0.5)).loop(4);

replace + reverse

tape = tape1.replace(2, 3, function(tape) {
  return tape.reverse();
});

gain

tape = Ciseaux.concat(tape1.split(25).map(function(tape, i) {
  return tape.gain(i / 25);
}));

pan

tape = Ciseaux.concat(tape1.split(25).map(function(tape, i) {
  return tape.pan(i % 2 ? -0.85 : +0.85);
}));

pitch

tape = Ciseaux.concat(tape1.split(25).map(function(tape, i) {
  return tape.pitch(i / 50 + 0.75);
}));

mix

tape = tape1.mix(tape2.gain(0.5), "fill").fill(30);

stutter

tape = Ciseaux.concat(tape2.split(16).map(function(tape) {
  return tape.loop(4).pitch(1.5);
})).fill(30);

phase

tape = Ciseaux.mix([ 1, 0.95 ].map(function(rate) {
  return tape2.pitch(rate).fill(30);
}));

lace

tape = Ciseaux.concat(tape1.split(32).map(function(tape, index) {
  return index % 2 ? tape2.pitch(2).fill(tape.duration) : tape;
})).fill(30);

concrete

tape = Ciseaux.mix([ -12, -10, -7, -3, 0 ].map(function(midi) {
  return tape1.pitch(Math.pow(2, midi * 1/12));
}), "fill").gain(0.5).fill(30);

sequence

tape = new Ciseaux.Sequence("a bdacbba babfeg", 0.2, {
  a: tape1.split(16)[0],
  b: tape1.split(16)[1],
  c: tape1.split(16)[2],
  d: tape1.split(16)[3].gain(0.15),
  e: tape2.split(16)[4].pitch(0.25),
  f: tape2.split(16)[5].pitch(4).gain(0.1),
  g: tape3.pitch(32),
}).apply().fill(30);

shuffled sequence

tape = new Ciseaux.Sequence("a bdaabcaccbgabb", {
  a: tape1.split(16)[4],
  b: tape1.split(16)[1],
  c: tape1.split(16)[2],
  d: tape1.split(16)[3].gain(0.15),
  e: tape2.split(16)[4].pitch(0.25),
  f: tape2.split(16)[5].pitch(4).gain(0.1),
  g: tape3.pitch(32),
}).apply([ 2/3, 1/3 ].map(function(x) { return x * 0.3; })).fill(30);

✂️ Developments

# Build : babel -> browserify -> uglify-js
npm run build

# Test : mocha + power-assert
npm run test

# Coverage : mocha + isparta
npm run cover

# Lint : jshint
npm run lint

✂️ Contributing

1. Fork it!
2. Create your feature branch: git checkout -b my-new-feature
3. Commit your changes: git commit -am 'Add some feature'
4. Push to the branch: git push origin my-new-feature
5. Submit a pull request :D

✂️ License

MIT