Video Tip: How to quickly add labels to background images in Tableau Labeling Background Images in Tableau Watch on Step 1: Open the background image in a tool like Snagit to get the dimensions. Write the dimensions down. Step 2: Create a data source. In this example, I created the outline of the data source in Excel and left the X/Y coordinates blank. Step 3: Connect to the data source created in step 2 in Tableau.