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166 CHAPTER 6 ■ VISION

• Sharpening: Sharpening/focusing an image
• Edge finding: finding edges
• Hough transform: Line finding

We’ll also use combinations of these filters to optimize and help us identify a beverage
from the refrigerator. For that, we’ll process three different-colored soda cans. They’re also
coincidentally colored red (Coke), green (7-Up), and blue (Pepsi). Or RGB for short.

What Is RGB?
RGB stands for red, green, and blue. The colors utilize an additive model. In this model, the
three colors are added together to form other colors (see Figure 6-1).

Figure 6-1. The RGB spectrum

For example, moving from the top left clockwise we have the following values:

Red = 255, 0, 0
Magenta = 255, 0, 255

Blue = 0, 0, 255
Cyan = 0, 255, 255
Green = 0, 255, 0

Yellow = 255, 255, 0