WAAPISim is a 'WebAudioAPI' polyfill fallbacking to the 'Audio Data API', or Flash.
In addition, even in WebAudio API ready browsers, add some latest method name for node-creation and start/stop if the browser does not support these method name.
WAAPISim automatically check the availability of APIs:
WebAudioAPI => AudioDataAPI => Flash
Chrome : WebAudioAPI is supported. WAAPISim do nothing.
Safari (include iOS) : WebAudioAPI is supported but old method name is used. WAAPISim add new method name for node-creation, start/stop and setTargetAtTime.
Firefox : Simulate using AudioDataAPI
Opera : Simulate using Flash
MSIE : Simulate using Flash. Float32Array is assigned to normal Array(IE9).
Not Support : MediaElementAudioSourceNode / MediaStreamAudioSourceNode / MediaStreamAudioDestinationNode / OfflineAudioCOntext
ConvolverNode : By performance reason, convolution is executed for only IR's first 1000 samples. Sebsequent part will be replaced as simple delays.
PannerNode : Simplified. Listener position should stay default. Source positions are interpreted as x-z 2d coordinate.
ScriptProcessorNode : Input buffer size should be 1024 and under (No limitation if use output only)
DynamicsCompressorNode : A little different characteristics from Chrome's implements.
Number of channels in each nodes should be 1 (mono) or 2(stereo)
createBuffer from ArrayBuffer and decodeAudioData supports only wav format.
k-rate AudioParam controls are executed only per 1024 samples frequency. a-rate AudioParams are controlled by sample.
Usage
Load the 'waapisim.js' before using the Web Audio API functions in your script.
<script type="text/javascript" src="waapisim.js"></script>
or
<script type="text/javascript" src="waapisim.min.js"></script>
To enable fallbacking to Flash, place the 'waapisim.swf' file to same folder as 'waapisim.js'.
Options
These lines should be specified before loading the 'waapisim.js'
<script type="text/javascript">waapisimLogEnable=1;</script>
Enable internal log info to console.
<script type="text/javascript">waapisimForceSim=1;</script>
Enable WAAPISim even if native WebAudioAPI is available.
<script type="text/javascript">waapisimForceSimWhenNotWebkit=1;</script>
Force enable WAAPISim when non-webkit browser.
some versions of Firefox have WebAudioAPI interfaces but not implemented completely (e.g. custom waveforms). Some apps may work better on Firefox with this flag.
<script type="text/javascript">waapisimForceSimWhenLackOsc=0;</script>
Disable WAAPISim if native WebAudioAPI is available even lacking oscillator function (means Firefox 23). This flag is default on (=1).
FIrefox 23 or ealier 's WebAudioAPI (need about:config flag setting) is very tentative. In default, WAAPISim ignore this version of WebAudoAPI.
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