var bmd:BitmapData = ImageSnapshot.captureBitmapData(someSprite);
trace("bmd size "+getSize(bmd));
var bounds:Rectangle = new Rectangle(0, 0, bmd.width, bmd.height);
var snapshot:ImageSnapshot = new ImageSnapshot(0,0,bmd.getPixels(bounds));
//var snapshot:ImageSnapshot = ImageSnapshot.captureImage(someSprite);
var file:FileReference = new FileReference();
file.save(snapshot.data,'abc.png');
In the above code after saving the file, when I try to open it, I get "This is not a valid bitmap file". I have tried 2-3 different viewers.