Before you can start working with your raster layer in ArcScan, you must ensure that the raster’s layer symbology is displayed as two unique colors. The ArcScan toolbar becomes active once the symbology is changed.
ArcScan supports any two colors so long as they are unique colors with unique color values. You can use the Unique Values rendering option to display the raster as two unique colors or the Classified option to display the raster as two classes.
- In the table of contents, right-click the raster layer and click Properties.
- Click the Symbology tab.
- There are two ways to symbolize a raster as two colors: with two unique values or classified with two classes.
- In the Show box, click the Unique Values option.
- In the Show box, click Classified. Then, in the Classification box, click the Classes drop-down arrow and click 2.
- Click OK.