的Flex，問題jpegencoding序列

Question

我創造這個「繪圖應用程序」，用戶可以點擊「預覽」，它會帶他們做了什麼，畫一個位圖，然後我想該位圖分成兩個位圖時左和右圖像。我創建第一個位圖，將其編碼爲JPEG，然後使用它來使用副本像素左右切割。然後，我在一幅畫布中將圖像與空間一起改造，然後繪製該畫布。在那裏一切工作正常。

當我去編碼新的位圖，然後提供它來保存，保存的圖像是空白的。到目前爲止，我已經測試過一切，並且一切正常。我在屏幕上看到了圖像，我可以將第一個位圖保存爲好..但第二個位置總是空白。這裏有一些示例代碼，可能有人可以幫助我。

_mainBmd = new BitmapData(_jacketWidth, _jacketHeight); 
_mainBmd.draw(_imageHolder); 
startEncode(_mainBmd); 


private function startEncode(imageBitmapData:BitmapData):void 
     { 
      var encoder:JPEGAsyncEncoder = new JPEGAsyncEncoder(100); 
      encoder.PixelsPerIteration = 150; 
      encoder.addEventListener(JPEGAsyncCompleteEvent.JPEGASYNC_COMPLETE, encodeDone); 

      encoder.encode(imageBitmapData); 


     } 

private function encodeDone(event:JPEGAsyncCompleteEvent):void 
     { 

_leftBmd = new BitmapData(sideWidth, sideHeight); 
      var lRect:Rectangle = new Rectangle(0,0, sideWidth, sideHeight); 
      var lPoint:Point = new Point(0,0); 
      _leftBmd.copyPixels(_mainBmd, lRect, lPoint); 


      _rightBmd = new BitmapData(sideWidth, sideHeight); 
      var bWidth:Number = 200; 
      var sWidth:Number = 111; 
      var rRectWidth:Number = (bWidth/2 + sWidth) * Constants.print_dpi; 
      var rRect:Rectangle = new Rectangle(rRectWidth, 0, sideWidth, sideHeight); 
      var rPoint:Point = new Point(0, 0); 
      _rightBmd.copyPixels(_mainBmd, rRect, rPoint); 

var lbm:Bitmap = new Bitmap(_leftBmd); 
      var rbm:Bitmap = new Bitmap(_rightBmd); 

      //now combine the two images into one holder with a space in the middle 


      //left Image 
      var l_Image:Image = new Image(); 
      l_Image.source = lbm; 

      //right image 
      var r_Image:Image = new Image(); 
      r_Image.source = rbm; 

var newRender:Canvas = new Canvas(); 
      newRender.clipContent = false; 
      newRender.minHeight = 0; 
      newRender.minWidth = 0; 

      newRender.addChild(l_Image); 
      r_Image.x = 500; 
      newRender.addChild(r_Image); 

fcBMD = new BitmapData(renderW, renderH); 
      fcBMD.draw(newRender); 

startEncode2(fcBMD); 


} 

private function startEncode2(imageBitmapData:BitmapData):void 
     { 
      var encoder:JPEGAsyncEncoder = new JPEGAsyncEncoder(100); 
      encoder.PixelsPerIteration = 150; 
      encoder.addEventListener(JPEGAsyncCompleteEvent.JPEGASYNC_COMPLETE, encode2Done); 

      encoder.encode(imageBitmapData); 


     } 

private function encode2Done(event:JPEGAsyncCompleteEvent):void 
     { 
      _data = event.ImageData; 


     } 

private function onSaveRenderClick(e:MouseEvent):void //save button listener 
     { 
      var fileRef:FileReference = new FileReference(); 
      fileRef.addEventListener(Event.SELECT, onSaveComplete); 
      fileRef.save(_data, 'testImage.jpg'); 
     } 

Answer 1

是否有特殊的理由，爲什麼你走線槽創建一個帆布架和添加圖像的所有的循環？

爲什麼不直接在要編碼的最後的BitmapData使用copyPixels：

var backgroundColor:uint = 0xffffff; 
fcBMD = new BitmapData(renderW, renderH, false, backgroundColor); 

var lPoint:Point = new Point(0,0); 
var lRect:Rectangle = new Rectangle(0,0, sideWidth, sideHeight); 
fcBMD.copyPixels(_mainBmd, lRect, lPoint); 

var rRect:Rectangle = new Rectangle(rRectWidth, 0, sideWidth, sideHeight); 
var rPoint:Point = new Point(renderW - sideWidth, 0); 
fcBMD.copyPixels(_mainBmd, rRect, rPoint); 

startEncode2(fcBMD);