Actionscript flex: Converting # colors to uint

Color is not a property, it is a style. You need to define the style like this:

[Style(name="labelColor", type="uint", format="Color" )]

(enclose it in tag if you define it directly in MXML). You then need to add some ActionScript to handle this style and apply it to whichever control you need, please refer to http://livedocs.adobe.com/flex/3/html/help.html?content=skinstyle_1.html for more information.

A friend and I were trying to do this a while back for a project, and found writing an inline method that does this in ActionScript to be incredibly slow. You have to scan each pixel and do a computation against it, but doing it with PixelBender proved to be lightning fast (if you can use Flash 10, otherwise your stuck with slow AS).

The pixel bender code looks like:

input image4 src;
output float4 dst;

// How close of a match you want
parameter float threshold
<
  minValue:     0.0;
  maxValue:     1.0;
  defaultValue: 0.4;
>;

// Color you are matching against.
parameter float3 color
<
  defaultValue: float3(1.0, 1.0, 1.0);
>;

void evaluatePixel()
{
  float4 current = sampleNearest(src, outCoord());
  dst = float4((distance(current.rgb, color) < threshold) ? 0.0 : current);
}

If you need to do it in AS you can use something like:

function threshold(source:BitmapData, dest:BitmapData, color:uint, threshold:Number) {
  dest.lock();

  var x:uint, y:uint;
  for (y = 0; y < source.height; y++) {
    for (x = 0; x < source.width; x++) {
      var c1:uint = source.getPixel(x, y);
      var c2:uint = color;
      var rx:uint = Math.abs(((c1 & 0xff0000) >> 16) - ((c2 & 0xff0000) >> 16));
      var gx:uint = Math.abs(((c1 & 0xff00) >> 8) - ((c2 & 0xff00) >> 8));
      var bx:uint = Math.abs((c1 & 0xff) - (c2 & 0xff));

      var dist = Math.sqrt(rx*rx + gx*gx + bx*bx);

      if (dist <= threshold)
        dest.setPixel(x, y, 0x00ffffff);
      else
        dest.setPixel(x, y, c1);
    }
  }
  dest.unlock();
}