About callout icons

Hello,

I sure I don't interstand how use callout graphics with images.

Is MediaObjectCO used to place callout icon over the imagedata ?

For exemple over a map picture (the town where I live) placing (1) over
my house and (2) over the church.

If it's possible, I suppose the secret in in the area corrds parameters.
But how it works ?

I have something like that :

<mediaobjectco>
            <imageobjectco>
                <imageobject>
                    <imagedata fileref="images/Map.jpg" id="Map"/>
                </imageobject>
                <area coords="40 62" id="house" units="other"/>
                <area coords="200 200" id="church" units="other"/>
            </imageobjectco>
        </mediaobjectco>
    <calloutlist>
        <callout arearefs="house">My House</callout>
        <callout arearefs="church">The church</callout>
    </calloutlist>
    
The only result I can have is the calloutlist. Nothing over the image.

Thanks again in advance,

Jacques
-- 
 C'est tout pour aujourd'hui !