AIR PNG Encoder from Javascript.

Hi there,

  How can I encode a Bitmap from AIR using the Javascript AIRAliases.js

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    var captureFile = air.File.applicationStorageDirectory.resolvePath( 'c:\capture.png' );

    var capture = new air.BitmapData( window.htmlLoader.stage.stageWidth,window.htmlLoader.stage.stageHeight );
    capture.draw( window.htmlLoader );
   
    var image = new air.Bitmap(capture,"NEVER",false);
       
    var png = ???

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