alexanderlerch / Aca Code

Matlab sources accompanying the book An Introduction to Audio Content Analysis - Applications in Signal Processing and Music Informatics by Alexander Lerch, [email protected]

Please note that the provided code examples as matlab functions are only intended to showcase algorithmic principles – they are not suited to be used without parameter optimization and additional algorithmic tuning.

The majority of these matlab sources require the Matlab Signal Processing Toolbox installed. Several scripts (such as MFCCs and Gammatone filters) are based on implementations in Slaney’s Auditory Toolbox.

Please feel free to visit http://www.audiocontentanalysis.org/code/ to find the latest versions of this code or to submit comments or code that fixes, improves and adds functionality.

The top-level functions are:

• ComputeFeature: calculates instantaneous features
• ComputePitch: calculates a fundamental frequency estimate
• ComputeKey: calculates a simple key estimate
• ComputeNoveltyFunction: simple onset detection
• ComputeBeatHisto: calculates a simple beat histogram

The names of the additional functions follow the following conventions:

• Feature*: instantaneous features
• Pitch*: pitch tracking approach
• Novelty*: novelty function computation
• Tool*: additional help functions such as frequency scale conversion, dynamic time warping, gammatone filterbank, ...

Example: Computation and plot of the Spectral Centroid

% read audio file from cWavePath
[afAudioData, fs] = wavread(cWavePath);

% compute SpectralCentroid
[v_sc,t] = ComputeFeature('SpectralCentroid', afAudioData, fs);

% plot result
plot(t,v), grid on, xlabel('t'), ylabel('v_sc')