Pick a color for transparency

This article provides info on how to pick a color for transparency in your map. Transparency can switch off any color from the original image on the final map. This option is typically used to eliminate the borders of multiple map sheets stitched together. You can set a specific color of the map to be considered fully transparent during rendering. MapTiler Engine 12 introduces this new feature to make color picking easier than ever before.

Pick a color

This feature is available in a Transparency combo box on the right side of the input page.

Now you can pick a color simply by hovering your mouse pointer over any place in the input image. The currently targeted color will appear in the top right circular preview.

Once you locate the desired color with your mouse pointer do a left-click. 

A pop-up will appear and you can review the “Previous transparency color” (white by default) and the “Current transparency color” (the one you select). You can also adjust the current transparency color in the color wheel if you click the “Adjust” button. Once you are done with your edits, just click “Set for this file”.

After you have just set the color for transparency, click the “Back” button to return to the window with the image preview. Do not worry, the “Continue” button is suppressed intentionally here.

After returning to the image preview, you can see the picked color code in the drop-down menu on the right. If you are satisfied with your results, continue to the export dialog by clicking the “Export” button.

Chose the coordinate system and the output format for your tiles. There are plenty to choose from.

Adjust the settings of your output file or leave them as they are. The default settings are calculated automatically to fit the size and resolution of your inputs so that you get the best output results.

Wait for the rendering to finish, it is going to take just a few seconds…

As soon as the rendering finishes, you can preview the rendered map tiles on the top of a basemap. Just look at how well the transparency works. All white borders of the input image are gone.

Useful links

How to overlay an image over a map
Select a color for transparency
Georeferencer functionalities