1. Lesson 1-15 AP Computer Science Principles
Encoding Color Images
Lesson 1-15
AP Computer Science Principles

2. Objectives Students will be able to:
Use the Pixelation Tool to encode small color images with varying bits-per-pixel settings.
Explain the color encoding scheme for digital images.
Use the Pixelation Tool to encode an image of the student’s design.
Explain the benefits of using hexadecimal numbers for representing long streams of bits

3. Journal
In the previous lesson we came up with a simple encoding scheme for B&W images.  What if we wanted to have color?
Devise an encoding scheme for color in an image file.  How would you represent color for each pixel?  
How many different colors could you represent?  Do you have a particular order to the colors?

4. Encoding Color
The way color is represented in a computer is different from the ways we represented text or numbers.
With text, we just made a list of characters and assigned a number to each one.
As you are about to see, with color, we actually use binary to encode the physical phenomenon of LIGHT. You saw this a little bit in the previous lesson, but today we will see how to make colors by mixing different amounts of colored light.

5. Video - A Little Bit about Pixels
During the video answer the questions on the worksheet

6. Activity Guide - 1
Video: How to use the pixelation widget to control color.
Task 1: Fill in the last two pixels with the missing colors

7. Activity Guide - 2 Video: more bits per pixel for more colors
Task 2: Experiment with 6-bit color

8. Activity Guide - 3 Video: Using hex to type bits more quickly
Task 3: Experiment with Hex

9. Hexadecimal Numbers

10. Activity Guide - 4 Complete the remainder of the activity guide.
Go on and create your Personal Favicon
Complete the Activity Guide.
Make sure you save your favicon!
Complete Stage 4!