inlinemedia figure

Title: inlinemedia figure

I have a few inlinemediaobjects in my document. They are used to display icons that are typically used in the toolbar in the application. The images themselves are 22x22, but when I generate the pdf file, the images are much larger than 22x22 (almost 2x as large). Is there a way to ensure they stay at their natural size?

This is how I include the icon:

<inlinemediaobject>

    <imageobject>

        <imagedata fileref="myicon.png"/>

    </imageobject>

</inlinemediaobject>

Thanks,

Jeff