quick demo of configurable bitrate

lepinsk · Apr 24, 2015 · f0802b2 · f0802b2
1 parent b4a1632
commit f0802b2
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Showing 3 changed files with 36 additions and 2 deletions.
diff --git a/example.html b/example.html
@@ -49,6 +49,11 @@ <h2>Options</h2>
     <input id="sampleRate" type="number" value="48000" />
   </div>
 
+  <div>
+    <label>bitRate</label>
+    <input id="bitRate" type="number" value="72000" />
+  </div>
+
   <h2>Commands</h2>
   <button id="init">init</button>
   <button id="start" disabled>start</button>
@@ -80,7 +85,8 @@ <h2>Log</h2>
         numberOfChannels: numberOfChannels.value,
         bitDepth: bitDepth.options[ bitDepth.selectedIndex ].value,
         recordOpus: recordOpus.checked,
-        sampleRate: sampleRate.value
+        sampleRate: sampleRate.value,
+        bitRate: bitRate.value
       });
 
       recorder.addEventListener( "start", function(e){

diff --git a/oggopus.js b/oggopus.js
@@ -8,6 +8,7 @@ var OggOpus = function( config ){
   this.maxBuffersPerPage = config.recordOpus.maxBuffersPerPage || 40; // Limit latency for streaming
   this.encoderApplication = config.recordOpus.encoderApplication || 2049; // 2048 = Voice, 2049 = Full Band Audio, 2051 = Restricted Low Delay
   this.encoderFrameSize = config.recordOpus.encoderFrameSize || 20; // 20ms frame
+  this.bitRate = config.bitRate;
   this.wavepcm = new WavePCM( config );
 
   this.pageIndex = 0;
@@ -139,6 +140,32 @@ OggOpus.prototype.initChecksumTable = function(){
 
 OggOpus.prototype.initCodec = function() {
   this.encoder = _opus_encoder_create( this.outputSampleRate, this.numberOfChannels, this.encoderApplication, allocate(4, 'i32', ALLOC_STACK) );
+
+  var bitrateLocation = _malloc(4);
+  HEAP32[bitrateLocation >>> 2] = this.bitRate;
+  _opus_encoder_ctl(
+    this.encoder,
+    4002, // OPUS_SET_BITRATE_REQUEST
+    bitrateLocation)
+  ;
+  _free(bitrateLocation);
+
+
+  var resultLocation = _malloc(4);
+  var resultLocationLocation = _malloc(4);
+  HEAP32[resultLocationLocation >>> 2] = resultLocation;
+
+  _opus_encoder_ctl(
+    this.encoder,
+    4003, // OPUS_GET_BITRATE_REQUEST
+    resultLocationLocation
+  );
+
+  var result = HEAPU32[resultLocation >>> 2];
+  _free(resultLocationLocation);
+  _free(resultLocation);
+  console.log("OPUS_GET_BITRATE=" + result);
+
   this.encoderBufferIndex = 0;
   this.encoderSamplesPerChannelPerPacket = this.outputSampleRate * this.encoderFrameSize / 1000;
   this.encoderBufferLength = this.encoderSamplesPerChannelPerPacket * this.numberOfChannels;

diff --git a/recorder.js b/recorder.js
@@ -147,7 +147,8 @@ Recorder.prototype.start = function(){
       inputSampleRate: this.audioContext.sampleRate,
       numberOfChannels: this.config.numberOfChannels,
       outputSampleRate: this.config.sampleRate,
-      recordOpus: this.config.recordOpus
+      recordOpus: this.config.recordOpus,
+      bitRate: this.config.bitRate
     });
 
     this.state = "recording";