comparison constant-q-cpp/README @ 366:5d0a2ebb4d17

Bring dependent libraries in to repo
author Chris Cannam
date Fri, 24 Jun 2016 14:47:45 +0100
parents
children
comparison
equal deleted inserted replaced
365:112766f4c34b 366:5d0a2ebb4d17
1
2 Constant-Q Library
3 ==================
4
5 A C++ library and Vamp plugin implementing the Constant-Q transform
6 of a time-domain signal.
7
8 https://code.soundsoftware.ac.uk/projects/constant-q-cpp
9
10 The Constant-Q transform is a time-to-frequency-domain transform
11 related to the short-time Fourier transform, but with output bins
12 spaced logarithmically in frequency, rather than linearly. The output
13 bins are therefore linearly spaced in terms of musical pitch.
14
15 This library provides:
16
17 * Forward transform: time-domain to complex Constant-Q bins
18 * Forward spectrogram: time-domain to interpolated Constant-Q
19 magnitude spectrogram
20 * Inverse transform: complex Constant-Q bins to time domain
21
22 The Vamp plugin provides:
23
24 * Constant-Q magnitude spectrogram with high and low frequency
25 extents defined in Hz
26 * Constant-Q magnitude spectrogram with high and low frequency
27 extents defined as MIDI pitch values
28 * Pitch chromagram obtained by folding a Constant-Q spectrogram
29 around into a single-octave range
30
31 The method is drawn from Christian Schörkhuber and Anssi Klapuri,
32 "Constant-Q transform toolbox for music processing", SMC 2010. See the
33 file CITATION for details. If you use this code in research work,
34 please cite this paper.
35
36 The implementation is reasonably fast and is causal, operating
37 block-by-block on the input, though with quite high latency
38 depending on the frequency range specified. By default it produces
39 output at a higher time resolution than some other implementations,
40 using multiple kernel atoms per time block. The inverse transform is
41 approximate rather than exact (see the paper for details).
42
43 The C++ implementation is by Chris Cannam, Copyright 2014-2015 Queen
44 Mary, University of London.
45
46 The library is provided under a liberal BSD/MIT-style open source
47 licence. See the file COPYING for more information.
48