Google Maps Ground Overlay: How to calculate bounds?

I'm working with the Google Maps API for the first time and I'm trying to append a simple image of a Building on top of my current map view.

This seems to be very straight forward when I look at the GMapsAPI here … https://developers.google.com/maps/documentation/javascript/overlays#GroundOverlays

However, I have no idea how to calculate the `bounds` and the exact position of my overlay.

As you can see in the documentation the position of the ground overlay is done via `LatLng`

``````var imageBounds = new google.maps.LatLngBounds(
``````

In my case I have no idea how to calculate those bounds. What are those values exactly? Why are there two seperate `LatLng` positions needed?

I have a simple .png of a building that I want to layer on top of an exact position. I get this position by entering the destination in Google Maps and reading the `Lat` and `Lng` values from the embed-code.

Is there a better way of doing this? Any ideas, tipps or tricks on how I could do this?

Or is it possible to calculate those `bounds` when I know the center of the image-position and the dimesions of my image file? (My image is 50x50px and a .png)

Kind Regards, Matt

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Most of the time when two coordinates are needed for a "bounds", it is looking for two corners of the image, such as the southwest corner and northeast corner. Or the other two corners. – MLowry Aug 6 '12 at 15:42
Yeah, but how do I get those corners? I know the exact coordinates of the center - that's just the center of the current destination of what I'm looking at inside google maps. But how do I get the corner-coordinates of a 50x50px image I want to center exactly on the coordinates I'm talking about. Is there a way to calculate the coordinates of the southwest and northeast corner when I know the center of the image and the dimensions of the image? I wonder how those coordinates and my pixel-values of the image are working together? – matt Aug 6 '12 at 17:40

You can use 'LatLng Marker' Google Map in Map Labs mode to find the Coordinates for your image.

Bottom Left is first, Top right is the second coordinate.

``````var imageBounds = new google.maps.LatLngBounds(