Computer Science 1033A/B Lecture Notes - Lecture 5: Lossless Compression, Huffman Coding, Lossy Compression

• School: Western University
• Department: Computer Science
• Course: Computer Science 1033A/B
• Professor: Laura Reid

Document Summary

Several different ways to do compression depending on the type of image. Rather than ascii (each letter is 8bits or 1 byte) use the least number of bits for common letters and more bits for less common letters. The human eye is more sensitive to brightness details than to fine colour details. If it finds two adjacent pixels with very similar colours, it will store both those pixels with the same colour and discard the other colour. Depends on the type of image we are representing. How many colours are needed for the image. The type of image we are trying to compress will determine the best file format to choose. Only supports 8 bit colour therefore doesn"t work well for images, but works well for clipart, logos, animation. Finds a pattern, and compresses it based on that pattern. Looks for large blocks of areas that all have the same colour.