Semi transparent png image saveing in flash 8

1

I am trying to save a png image which has different alpha value in it, but its taking 100% alpha value only. This image has 100% and 40% alpha value. Please advice. Thanks in advance.

part of my code:

var myBitmapData:BitmapData = new BitmapData(MainContainerMC._width, MainContainerMC._height, true, 0x00FFFFFF);
myBitmapData.draw(MainContainerMC);
var mc:MovieClip = this.createEmptyMovieClip(“mc”, this.getNextHighestDepth());
mc.attachBitmap(myBitmapData, this.getNextHighestDepth(), “auto”, true);
var saveTracker:MovieClip = _root.createEmptyMovieClip(“saveTrack_mc”, 123);
var counter = 0;
var i = 0;

saveTracker.onEnterFrame = function() {

    for (var j = 0; j<=MainContainerMC._height; j++) {
       var alpha:String = (myBitmapData.getPixel32(i, j) >> 24 & 0xFF).toString(16);
        var red:String = (myBitmapData.getPixel32(i, j) >> 16 & 0xFF).toString(16);
        var green:String = (myBitmapData.getPixel32(i, j) >> 8 & 0xFF).toString(16);
        var blue:String = (myBitmapData.getPixel32(i, j) & 0xFF).toString(16);
        if(alpha.length == 1){
            alpha = "0" + alpha ;
        }
        if(red.length == 1){
            red = "0" + red ;
        }
        if(green.length == 1){
            green = "0" + green ;
        }
        if(blue.length == 1){
            blue = "0" + blue ;
        }
        PixelValue += ("alpha:"+alpha+"#red:"+red+"#green:"+green+"#blue:"+blue+"#");

        counter++;
    }
    perc = int((i*100)/MainContainerMC._width);
    i++;
    
    op.text = "collecting pixels value: "+perc+" %";
    if (i>MainContainerMC._width) {
        sendData();
        delete this.onEnterFrame;
    }
};