Matlab mfcc函数参数详解（英文附例）

Matlab mfcc函数参数详解

其实可以直接打开源代码看哈。

%MFCC Extract the mfcc, log-energy, delta, and delta-delta of audio signal
%   coeffs = MFCC(audioIn,fs) returns the mel-frequency cepstral
%   coefficients over time for the audio input. Columns of the input are
%   treated as individual channels. coeffs is returned as an L-by-M-by-N
%   array.
%       L - Number of frames the audio signal is partitioned into.
%           This is determined by the WINDOWLENGTH and OVERLAPLENGTH 
%           properties.
%       M - Number coefficients returned per frame.
%           This is determined by the NUMCOEFFS property.
%       N - Number of channels.
%       
%   coeffs = MFCC(...,'WindowLength',WINDOWLENGTH) specifies the analysis
%   window length used to calculate the coefficients. Specify the window
%   length in samples as a positive scalar. If unspecified, WINDOWLENGTH
%   defaults to round(0.030 * fs).
%
%   coeffs = MFCC(...,'OverlapLength',OVERLAPLENGTH) specifies the number
%   of samples overlap between adjacent windows. Specify the overlap length
%   as a scalar smaller than the window length. If unspecified,
%   OVERLAPLENGTH defaults to round(fs*0.02).
%
%   coeffs = MFCC(...,'NumCoeffs',NUMCOEFFS) specifies the number
%   of coefficients returned for each window. If not specified, the number
%   of coefficients is 13.
%
%   coeffs = MFCC(...,'FFTLength',FFTLENGTH) specifies the FFT length. By
%   default, the FFT length is set to the WINDOWLENGTH.
%
%   coeffs = MFCC(...,'DeltaWindowLength',DELTAWINDOWLENGTH) specifies the
%   delta and delta-delta window length. The default is 2.
%
%   coeffs = MFCC(...,'LogEnergy',LOGENERGY) specifies if and how the log
%   energy is used. Specify log energy as a character vector:
%       'Append'  - Adds the log-energy as the first element of the
%                   returned coefficients vector. This is the default
%                   setting.
%       'Replace' - Replaces the zeroth coefficient (first element of
%                   coeffs) with the log-energy.
%       'Ignore'  - Ignores and does not return the log-energy.
%
%   [coeffs,delta,deltaDelta,loc] = MFCC(...) returns the delta,
%   delta-delta, and location in samples of each window of data. The
%   location is the most recent sample used to calculate the coefficients.
%   The delta and delta-delta vectors are derived from how the coeffs
%   vector was specified. For example, if 'LogEnergy' is set to 'Replace',
%   the first element of the coeffs vector is the log-energy, and the first
%   element of the delta vector is the delta of the log-energy.
%
%   EXAMPLE 1: Get the mel-frequency cepstral coefficients for entire
%   speech file
%     % Use the default settings to extract the MFCC feature from a speech 
%     % file.
%
%       [audioIn,fs] = audioread('Counting-16-44p1-mono-15secs.wav');
%       [coeffs,delta,deltaDelta,loc] = mfcc(audioIn,fs);