How to overlay an image over a map

Creating your own map by overlaying an image over an online map is very easy with MapTiler Engine. This article will teach you how to master the whole process step-by-step.

Go and download MapTiler Engine for free, activate the trial, and test the full functionality yourself!

Opening a file

First, start the MapTiler Engine application and simply drag & drop an image: an aerial photo, a drawing made in GIS, Photoshop, AutoCAD, a picture of an old map, or anything you wish to visualize in your map. You can also select a file from the file dialog by clicking the "Open a file" button.

Setting the coordinate system

In most cases, the coordinate system suggested by MapTiler Engine should be fine, but you can also select the one which best fits your needs. To change the settings, use the "Find coordinate systems" option from the "Coordinates" menu located on the right-hand side of the window. 

Georeferencing

The next step in the process is to give your image a correct position on the map. To do so, navigate to the "Assign location visually"  button from the "Geolocation" menu. You'll see the georeferencing tool pop up. Assign control points to the same places on both of the maps: your image and online map. There is a minimum of three control points to ensure your image will be placed in the same spot as it is in reality. The more control points you add, the more precise result you get.

After assigning the control points you can check the position on the map and adjust again if necessary. If everything seems to be OK, click on the "Export" button.

Choosing the output format

Now, choose whether you want to render your map into the Folder, MBTiles, or GeoPackage format and click on the "Continue" button.

On the next page, you can choose the settings like the format of the tiles, or the zoom levels of your map. However, using the default settings should produce satisfying results. Proceed by clicking the "Render" button and choosing the output directory for your map.

Previewing the results

When the rendering is complete, you'll see the preview of your map with your picture perfectly matched with its geographical position.

Publishing your map

Now you can either use your map from the same computer or upload it to MapTiler Cloud or any other web hosting or cloud service.

Useful links

Georeferencing
Uploading a map to MapTiler Cloud
Choosing the right output format for your map
Choosing the coordinate reference system in MapTiler Engine