PCP Teaser

Lecture: Audio Features

After working through the material of this lecture, you should be able to answer the following questions:

  • What is the relation between musical pitches and frequency?
  • How can one assign a frequency range to a given musical pitch? How are a cutoff frequency and a bandwith defined?
  • What is a log-frequency spectrogram? How can it be computed? (See Eq. 3.3 and Eq. 3.4.)
  • What is the motivation for introducing chroma features? Which musical aspects are captured by these features?
  • How can one compute chromagrams? (See Eq. 3.6.)
  • What is the goal of logarithmic compression? How is it computed? (See Eq. 3.7.)
  • What is the goal of feature normalization? How can it be computed? (See Eq. 3.9 and Eq. 3.10.)
  • What are the effects of tuning deviations on the quality of chroma features? How may one handle such deviations?
  • How can one adapt chroma features to simulate musical transpositions?

Reading Assignments

Müller, FMP, Springer 2021
Chapter 3: Music Synchronization

  • Section 3.1: Audio Features
    • Section 3.1.1: Log-Frequency Spectrograms
    • Section 3.1.2: Chroma Features
  • Exercises
    • Exercise 3.3
    • Exercise 3.6

Slides and Notes

Videos

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