First, enter a URL or use the provided auto-complete
options to load an image. Next, select image regions using
either the Color Picker or Magic Wand tools.

Color Picker Tool
Click or drag on the image to see matching color names.
Click a color name to select all matching imaging pixels.
Adjust the tolerance to change the name-matching threshold.

Magic Wand Tool
Click the image to select an image region.
Adjust the RGB slider to change the RGB similarity threshold.
Adjust the Name slider to change the name-matching threshold.
For large regions, the wand may take a moment to complete.