How to composite argb image data on top of xrgb image data
<p>I have a pointer to an 32bit argb image's pixel data and a 32bit xrgb image's pixel data.  How can I composite the argb on top of xrgb image while making use of the alpha component?</p>

<p>Visual Studio 2008 C++</p>

<p>Edit:</p>

<p>Is there a quicker (faster processing) way to do the compositing than this:</p>

<pre><code>        float alpha = (float)Overlay[3] / 255;
        float oneLessAlpha = 1 - alpha;
        Destination[2] = (Overlay[2] * alpha + Background[2] * oneLessAlpha);
        Destination[1] = (Overlay[1] * alpha + Background[1] * oneLessAlpha);
        Destination[0] = (Overlay[0] * alpha + Background[0] * oneLessAlpha);
</code></pre>
