1. MED 2001 Advanced Media Production
Lecturer: Stefan Lutschinger

2. Lesson Plan
Theory of computer graphics
The basics:
What is resolution?
What are image file formats?
What are colour models?
Practical exercise
Brochure

3. A. What is resolution? Unit of measurement: DPI: dots per inch Screen:
Print:
150 dpi or more (300)

4. B. Image file formats: Concepts
Types:
Vector graphics vs. bitmap images
Bitmap images:
Indexed vs. true colour
Uncompressed vs. compressed
Compression:
Lossy vs. lossless

5. B. Image file formats: Examples
Raster images:
JPG: bitmap image, true colour, compressed, lossy
GIF: bitmap image, indexed, compressed (LZW), lossless
RAW: bitmap image, true colour uncompressed, lossless
TIFF: bitmap image, true colour compressed (LZW), lossless
Vector graphics:
AI (Adobe Illustrator)
Compound formats:
PDF
INDD (Adobe InDesign)

6. C. Colour models True colour: Indexed: Formats: Formats:
GIF, PNG 8-bit
256 colours
Alpha-channel (transparency)
A colour palette refers to colour values (flexible)
Special features for web, like animation.
True colour:
Formats:
JPG, RAW, TIFF
16.7 mill colours
No alpha-channel
Each primary colour value is stored numerically in 8-bit (256 shades)
256 red x 256 blue x 256 green = 16.7 mill colours

7. Additive color mixing: (Screen) Subtractive color mixing: (Print)
Three overlapping lightbulbs in a vacuum, adding together to create white.
Three splotches of paint on white paper, subtracting together to turn the paper black.

8. A 10 × 10-pixel image on a computer display usually requires many more than 10 × 10 printer dots to accurately reproduce, due to limitations of available ink colors in the printer. The whole blue pixels making up the sphere are reproduced by the printer using cyan, magenta, and black.

9. Download exercise at: