How to get a DisplayObject’s BitmapData
There are many uses to using a DispalyObject’s (MovieClip, Sprite, Loader, etc…) BitmapData. The main reason I find myself using it for is for scaling an image I loaded smoothly. I load the image from an external source, then pull it’s BitmapData and set it’s smoothing to true. Then I can scale the new image without it getting too grainy or pixelated. This is the same effect as selecting the “Allow Smoothing” checkbox if you are using a Bitmap from the library.
In this example, we will get the BitmapData from our MovieClip (myMC) and create a new Bitmap (b), then add it to the stage:
var bd:BitmapData = new BitmapData(myMC.width, myMC.height, true,0xFFFFFFFF);
bd.draw(myMC);
var b:Bitmap = new Bitmap(bd);
addChild(b);
I used the BitmapData.draw() method to pull the movie clip’s (myMC) pixel information. I can then use that data when creating a new Bitmap. All that is left is to add the new Bitmap (b) to the display tree (addChild).

Thanks, I just want to know that as well.
But there should be a reason right ? when we need this bitmap data out of the ability MovieClip, Sprite, etc do the job for us. For my case, I use your solution to load the external resource (it automatically loaded as DisplayObject) and get its BitmapData to inject into the Entity’s image of some flash 2d engine.
THanks
Found this useful for same technique haxpor mentions: Loading animated PNG sequences as DisplayObjects then injecting their bitmapData into Bitmaps on the stage. Thanks for saving me a headache!