4) Specifying Colors I

📖 About

A big aspect of any visual display has to do with color, which involves two major aspects:

1. Specification of colors, and

2. Use of colors (encoding data with color).

In this unit and the next one, we’ll talk about how can we specify—in a computational sense—a certain color. In other words: How do we tell a computer program what kind of color we want to use? The answer to this question is given by Color Models, and their associated color spaces (or geometric volumes).

The topic of this unit is the so-called RGB (Red-Green-Blue) Color Model. Also, we describe the geometric space of such color model, as well as the use of hexadecimal notation for expressing RGB values.

🎯 Objectives

At the end of this unit you will be able to:

• Explain the Trichromatic theory of color vision.

• Explain how to specify colors under the RGB color model.

• Describe the geometric space associated to the RGB model.

• Indicate how to use hexadecimal notation to express RGB values.

• Describe what the alpha value (or alpha channel) is used for.

🌠 Slides

Trichromatic Theory (google slides)

RGB Color Model (google slides)

💻 Code

TBA

📖 Assignment

TBA