Compression Techniques

Lossy compression

• May result in loss of detail compared to the original file 
• Make a decision about what parts of sounds are important and discards other information
• Only keeps sounds human ear can process and discards the rest
• It then applies lossless technique for further reduction 
• Can reduce 90% (reduce to 10%) - smaller file size, less time to transmit
• E.g. .jpeg, .mp3

Lossless compression

• Designed to lose none of the original detail
• The technique is based on some form of replacement like RLE or FLAC
• Maximum compression is about 50%

RLE (run-length encoding)

• Reduces a string of adjacent, identical characters that are encoded into 2 like (code of char, count of char)