Flash Actionscript 多线程Worker 压缩图片

package
{
        import flash.display.Bitmap;
        import flash.display.Sprite;
        import flash.events.Event;
        import flash.external.ExternalInterface;
        import flash.geom.Rectangle;
        import flash.system.MessageChannel;
        import flash.system.Worker;
        import flash.system.WorkerDomain;
        import flash.utils.ByteArray;public class WorkerTest extends Sprite
       {
               protected var mainToWorker:MessageChannel;
               protected var workerToMain:MessageChannel;
              
               protected var worker:Worker;
              
              [ Embed(source= "1.jpg")]
               public var Image1:Class;
              
               public function WorkerTest()
              {
                      /**
                      * Start Main thread
                      **/
                      if(Worker.current.isPrimordial){
                            //Create worker from our own loaderInfo.bytes
                           worker = WorkerDomain.current.createWorker(this.loaderInfo.bytes);
                           
                            //Create messaging channels for 2-way messaging
                           mainToWorker = Worker.current.createMessageChannel(worker);
                           workerToMain = worker.createMessageChannel(Worker.current);
                           
                            var byteArray:ByteArray = Bitmap(new Image1()).bitmapData.getPixels(new Rectangle(0,0,300,300));
                           byteArray. shareable = true;        //使bytearray可以在两个线程中使用
                           
                            //Inject messaging channels as a shared property
                           worker.setSharedProperty( "data", byteArray);
                           
                            //Listen to the response from our worker
                           workerToMain.addEventListener(Event.CHANNEL_MESSAGE, onWorkerToMain);
                           
                            //Start worker (re-run document class)
                           worker.start();
                           
                     }
                      /**
                      * Start Worker thread
                      **/
                      else {
                           
                            //Inside of our worker, we can use static methods to
                            //access the shared messgaeChannel's
                            var data:ByteArray = Worker.current.getSharedProperty( "data");
                           workerToMain = Worker.current.getSharedProperty( "workerToMain" );
                           
　　　　　　　　　　　　　　　　//这里可以做一些压缩的工作
　　　　　　　　　　　　　　　　data.compress();
                           workerToMain.send(data);　　//只要byteArray是shareable的，可以直接send
                           
                     }
              }
              //Messages to the worker thread
               protected function onWorkerToMain(event:Event): void {
                      //Trace out whatever message the worker has sent us.
                      var a:* = workerToMain.receive();
                      trace("[Worker] " + a);
                     ExternalInterface.call( "alert", a);     //debug版Flashbuilder4.6运行会收不到消息，但release版或断开debug连接就没问题
              }
       }
}