Filereference.save from multiple loaders?

Question

Hey folks,
I need to make a way for a user to save a sample of an image once a user uploaded image is uploaded onto it.
This means I have to use multiple loaders, right?
So, I can get the bacround image to save just fine. but when I add the container for the logo, I get a reference error. More specifically-
[CODE]
ReferenceError: Error #1069: Property FileName.jpg not found on flash.utils.ByteArray and there is no default value.
[/CODE]
Here is my script-
[CODE]
sampleSaveBTN.addEventListener(MouseEvent.CLICK, saveSampleImage);
function saveSampleImage (evt: MouseEvent)
var bitmapData:BitmapData = new BitmapData(BGContain.width, BGContain.height);
var logoBitmapData:BitmapData = new BitmapData(logoContain.width, logoContain.height);
bitmapData.draw(BGContain);
logoBitmapData.draw(logoContain);
var jpg:JPGEncoder = new JPGEncoder(100);
var ba:ByteArray = jpg.encode(bitmapData);
var la:ByteArray = jpg.encode(logoBitmapData);
file = new FileReference();
file.save[ba,la, 'FileName.jpg'];
[/CODE]

Answer 1

I was able to get it to roughly work with the following:
http://stackoverflow.com/questions/9063990/how-can-i-merge-multiple-bitmapdata-objects-int o-one-so-that-it-can-be-encoded-u?rq=1
Here is the code- I added the children from the previous containers. Their loader positions are gone, but I feel like I'm on the right track now!
function saveSampleImage (evt: MouseEvent)
    var gatherSample: Sprite = new Sprite();
    gatherSample.addChild(bgImgLoader);
    gatherSample.addChild(loadLogo);
    matrix = color.CalculateFinalFlatArray();
    colorMatrix = new ColorMatrixFilter (matrix);
    filterBW = [colorMatrix];
    loadLogo.filters = filterBW;
    var sampleData: BitmapData = new BitmapData(gatherSample.width, gatherSample.height);
    sampleData.draw(gatherSample);
var jpg:JPGEncoder = new JPGEncoder(100);
var ba:ByteArray = jpg.encode(sampleData);
file = new FileReference();
file.save(ba,'FileName.jpg' + ".jpg");
Thanks again!