1	Tonality visualization of polyphonic audio {emilia.gomez,jordi.bonada}@iua.upf.es Music Technology Group, Pompeu Fabra University www.iua.upf.edu/mtg 5th of September 2005
2	Index Introduction Tonal analysis Feature computation from audio signals Tonality estimation Conclusions
3	Introduction Key: Mozart’s Sonata in F Major KV 533-494, not always available Often poor as a tonal description Pieces rarely maintain a single tonality Modulations Atonality Proposal Represent instantaneous evolution of the tonality of a piece and its strength Analyze audio (not MIDI): adapt methods proposed for MIDI Applications Musical analysis Music similarity Structural analysis Genre classification
4	Tonal analysis Much (multidisciplinary) research on the analysis of score: global key determination, less to locate modulations. Less dealing with audio
5	Approach for tonal analysis
6	Approach for tonal analysis
7	Feature computation Representation of the pitch class distribution of a piece Tuning frequency (with respect to A-440 Hz) Harmonic Pitch Class Profile (relative intensity of each of the 12 semitones of the temperate octave)
8	Feature computation
9	Feature computation: interval resolution
10	Feature computation: temporal resolution
11	Approach for tonal analysis
12	Key/chord estimation Correlation of features with a tonal model: Krumhansl’s & Schmuckler (1990) – Temperley (1999) Sliding window: window size can be changed: small-chords, large-key
13	Key/chord evolution (sliding window)
14	Key/chord estimation Harmonic network
15	Key/chord evolution (sliding window): version ID
16	Key/chord evolution: multi-resolution approach From Sapp (2001)
17	Conclusions Different views for tonal analysis of polyphonic audio. The tool (and videos) can be downloaded from www.iua.upf.es/~egomez/TonalDescription/GomezBonada-ICMC2005.html
18	Tonality visualization of polyphonic audio {emilia.gomez,jordi.bonada}@iua.upf.es Music Technology Group, Pompeu Fabra University www.iua.upf.edu/mtg 5th of September 2005