lbmrn-pcm-utils/lib/unzipper.js

PCM audio utilities for Node.js

// Generated by CoffeeScript 1.11.1
var Unzipper, binding, pcm, stream,
  extend = function(child, parent) { for (var key in parent) { if (hasProp.call(parent, key)) child[key] = parent[key]; } function ctor() { this.constructor = child; } ctor.prototype = parent.prototype; child.prototype = new ctor(); child.__super__ = parent.prototype; return child; },
  hasProp = {}.hasOwnProperty;

binding = require('../build/Release/binding');

stream = require('stream');

pcm = require('./constants');

Unzipper = (function(superClass) {
  extend(Unzipper, superClass);

  function Unzipper(channels, format) {
    var i, ref;
    this.channels = channels != null ? channels : 2;
    this.format = format != null ? format : pcm.FMT_F32LE;
    stream.Writable.call(this);
    this.alignment = pcm.ALIGNMENTS[this.format];
    this.unzipper = new binding.Unzipper(this.channels, this.alignment);
    this.outputs = (function() {
      var j, ref, results;
      results = [];
      for (i = j = 0, ref = this.channels; 0 <= ref ? j < ref : j > ref; i = 0 <= ref ? ++j : --j) {
        results.push(new stream.PassThrough);
      }
      return results;
    }).call(this);
    if (this.channels === 1) {
      this.mono = this.outputs[0];
    }
    if (this.channels === 2) {
      ref = [this.outputs[0], this.outputs[1]], this.left = ref[0], this.right = ref[1];
    }
  }

  Unzipper.prototype._write = function(chunk, encoding, callback) {
    return this.unzipper.unzip(chunk, (function(_this) {
      return function(err, chunks, done) {
        var i, j, len;
        if (err != null) {
          throw err;
        }
        for (i = j = 0, len = chunks.length; j < len; i = ++j) {
          chunk = chunks[i];
          _this.outputs[i].write(chunk);
        }
        if (done) {
          return callback();
        }
      };
    })(this));
  };

  return Unzipper;

})(stream.Writable);

module.exports = Unzipper;