# Introduction

## Features

The following algorithms are implemented:

- Window
- Unwrap
- Fast Fourier Transform (FFT / IFFT) (wrapper around libfftw [http://www.fftw.org/])
- Discrete Cosine Transform (DCT)
- Filter and BandFilter (based on Scipy [http://www.scipy.org/] implementation):
- Band type
- LowPass
- HighPass
- BandPass
- BandStop

- Filter type
- Chebyshev I
- Chebyshev II
- Bessel
- Butterworth

- Band type
- Correlation / Autocorrelation
- Direct calculation
- FFT based calculation

- Resample (wrapper around libsamplerate [http://www.mega-nerd.com/SRC/])
- Onset Detection Functions:
- High Frequency Content (HFC)
- Flux
- Phase Deviation
- Complex Domain
- Modified Kullback-Liebler
- Peak Center of Gravity

- Pitch Estimation:
- Autocorrelation Function based (ACF)
- Inverse Problem based

- Spectral Bands
- Mel bands

- MFCC
- LPC
- Sinusoidal Modelling:
- Peak Detection
- Peak Interpolation
- Peak Tracking

- Spectral Whitening
- Spectral Noise Suppression
- Non-negative Matrix Factorization (NMF)
- Other experimental and/or unfinished algorithm implementations
- Spectral Reassignment
- Adaptative Optimized Kernel (AOK) (modification of AOK 4.1 [http://www.macunix.net/aok.html])
- Peak Synthesis
- Incremental Non-negative Matrix Factorization (INMF)
- LPC residual

Numerous examples which can also be used for testing in some cases can be found in python/ Some of the examples require an audio WAVE filename as input argument.

# Credits

# License

Loudia is Free Software licensed under GNU General Public License version 3 or later