vorbis.js

This combines work from Alex Barkan ( vorbis.cpp ) and effort from Salehen Rahman who, in turn, forked, Devon Govett's original repo

##What it is

This spits out a javascript file that can be used in the browser to convert PCM audio data to compressed ogg vorbis audio.

Build

• Ensure that you have the emscripten installed.
  • i.e. you need access to emcc

git submodule init
git submodule update
./compileOgg.sh
./compileVorbis.sh
./build.sh

These steps will output vorbis.js

Example

<script src='vorbis.js'></script>
<script>
  
  
  /* 
    Imagine stream is an audio stream emitting appropriate PCM buffers.
    
    See ScriptProcessorNode in the Web Audio API for how all this happens
    in the wild. Long story short it goes like: node.onaudioprocess = fn
    
    ( https://dvcs.w3.org/hg/audio/raw-file/tip/webaudio/specification.html )
  */
  
  // _lexy_encoder_start accepts sampleRate and compression quality ( 0-10 )
  var state = Module._lexy_encoder_start(44100, 3);

  stream.on('write', function(left_buffer, right_buffer) {

    // Allocate memory using _malloc
    var left_buffer_ptr = Module._malloc( left_buffer.length * left_buffer.BYTES_PER_ELEMENT );
    var right_buffer_ptr = Module._malloc( right_buffer.length * right_buffer.BYTES_PER_ELEMENT );

    // Set the buffer values in memory
    Module.HEAPF32.set( left_buffer, left_buffer_ptr>>2 );
    Module.HEAPF32.set( right_buffer, right_buffer_ptr>>2 );

    // Write data to encoder
    Module._lexy_encoder_write( state, left_buffer_ptr, right_buffer_ptr, buffer_length );

    // Free the memory
    Module._free( left_buffer_ptr );
    Module._free( right_buffer_ptr );
  }

  stream.on('finish', function() {
    Module._lexy_encoder_finish( state );
    var ogg_ptr = Module._lexy_get_buffer( state );
    var ogg_data = Module.HEAPU8.subarray( ptr, ptr + Module._lexy_get_buffer_length( state ) );

    var ogg_blob = new Blob([ ogg_data ], {
      type: 'audio/ogg'
    });
  });
</script>

MIT License

Copyright (c) 2014 Joe Sullivan

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.