1. Graphics: Conceptual Model Real Object Human Eye Display Device Graphics System Synthetic Model Synthetic Camera Real Light Synthetic Light Source

2. Raster Image and Output Device

3. Pixels and Frame Buffer The image is made up of many small cells The image is made up of many small cells The individual cells are called Pixels The individual cells are called Pixels A raster image is stored in a computer as an array of numerical values. The array is called a Pixel Map. If the value is only 0 and one, then it is called a bitmap A raster image is stored in a computer as an array of numerical values. The array is called a Pixel Map. If the value is only 0 and one, then it is called a bitmap The memory that stores the pixels are called Frame buffer. The memory that stores the pixels are called Frame buffer.

4. 4 Figures are extracted from Angel's book (ISBN 0-201-38597-x) Pixels and Image

5. Gray-scale Raster Images bi-level: one bit per pixel bi-level: one bit per pixel pixel depth: the number of bits for each pixel pixel depth: the number of bits for each pixel 2 produced 4 gray level, what about n? 2 produced 4 gray level, what about n? Effect of Pixel depth Effect of Pixel depth

6. Color Raster Image Ordered triple RGB Ordered triple RGB The number of bits used to represent the color of each pixel is called the color depth The number of bits used to represent the color of each pixel is called the color depth 24 bits (true color), memory? 24 bits (true color), memory?

7. Raster displays Display surface Display surface Frame buffer Frame buffer Scanning Process Scanning Process

8. How Does Monitor Work? http://il.youtube.com/watch?v=Gnl1vuwjHto &feature=related http://il.youtube.com/watch?v=Gnl1vuwjHto &feature=related

9. Video Monitor Cathode-ray tube CRT Cathode-ray tube CRT RGB each 2 bits, total color? RGB each 2 bits, total color? Refresh rate, flicker Refresh rate, flicker

10. Indexed Color and Lookup Table

11. How many colors can a system display Color depth: b bits Color depth: b bits LUT entry: w bits LUT entry: w bits the system can display 2 w colors, 2 b at one time the system can display 2 w colors, 2 b at one time Number of pixels in Frame buffer: M Number of pixels in Frame buffer: M Frame Buffer size: M * b (bits) Frame Buffer size: M * b (bits) LUT size: w *2 b (bits) LUT size: w *2 b (bits)