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0 index
1 Raster Graphics Essentials
2 Raster Graphics
3 The most basic Image
4 Storing the image as binary numbers
5 Looking at colors
6 Examing basic RGB colors
7 A simple RGB face
8 Data for the RGB face
9 Examining 24-bit Colors
10 Raster Graphics Essentials
11 Other Color Schemes
12 RGB
13 HSV Scheme
14 Understanding Hue
15 Saturation
16 Value
17 Subtractive Color Schemes

outline
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Raster Graphics Essentials

1. Raster Graphics Essentials



































Raster Graphics Essentials

2. Raster Graphics

  • Use numbers to store images
  • An image is a matrix of numbers


































Raster Graphics Essentials

3. The most basic Image



































Raster Graphics Essentials

4. Storing the image as binary numbers



































Raster Graphics Essentials

5. Looking at colors

  • Cones in the human eye


































Raster Graphics Essentials

6. Examing basic RGB colors

  • Spotlight Page at Explore Science
  • NOTE: This is an external link. You must have a live web connection
  • to view it. It is possible the site owner could move or remove this site at some point.


































Raster Graphics Essentials

7. A simple RGB face

  • Each pixel has three dots
  • Red, Green Blue
  • Each can be on or off


































Raster Graphics Essentials

8. Data for the RGB face



































Raster Graphics Essentials

9. Examining 24-bit Colors

  • The RGB applet
  • height = "200"
  • width = "200">
  • This page requires that java be enabled
  • Use 8 bits each for red, green, and blue


































Raster Graphics Essentials

10. Raster Graphics Essentials



































Raster Graphics Essentials

11. Other Color Schemes



































Raster Graphics Essentials

12. RGB

  • Often 3, 4, or 24 bits / pixel
  • Relate to how computer stores colors
  • Does not clearly indicate relationships between colors
  • How do you make a color lighter or darker?


































Raster Graphics Essentials

13. HSV Scheme

  • Hue, Saturation, Value
  • Closer to color wheel
  • Better representation of color relationships
  • Often measured in percentages (0-100)


































Raster Graphics Essentials

14. Understanding Hue

  • Base color
  • 'pure' colors (FF0000, 00FF00, FFFF00, etc) easily created
  • All bright colors
  • Basic color wheel
  • Nothing dark, Nothing pastel
  • Hue of 0 = Red, 100 = Red


































Raster Graphics Essentials

15. Saturation

  • Relationship between 'pure' hue and grayscale
  • High Saturation = pure colors
  • Low Saturation = grayscale


































Raster Graphics Essentials

16. Value

  • Convert to black and white
  • Relative grayscale - brightness
  • High Values = lighter colors
  • Low Values = darker colors


































Raster Graphics Essentials

17. Subtractive Color Schemes

  • Used in printing
  • CMY - Cyan, Yellow, Magenta
  • CMYK - Cyan, Yellow, Magenta, Black


































outline

Raster Graphics Essentials

Raster Graphics

The most basic Image

Storing the image as binary numbers

Looking at colors

Examing basic RGB colors

A simple RGB face

Data for the RGB face

Examining 24-bit Colors

Raster Graphics Essentials

Other Color Schemes

RGB

HSV Scheme

Understanding Hue

Saturation

Value

Subtractive Color Schemes