Compressed audio representations

·   Save bits on quantization

- variable quantization (mu-law, ADPCM)
- noise shaping & `perceptual coding'

·   Parametric models use stronger constraints

- approximate signal as output of a process
- how to extract/find best parameters?
- size vs. quality vs. complexity

·   Event decomposition


- encode high-level temporal structure
- e.g. MIDI, MPEG-4
- implies a synthesis method...