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我正在使用現在包含Matching Pursuit算法的MATLAB 2013。 它有一個功能叫wmpdictionary創建一個字典。據我所知，能夠使用下一個函數來創建在字典中的原子：MATLAB匹配使用Gabor或自定義原子的追蹤wmpdictionary
- 離散餘弦變換-II基礎
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- 多項式
- 移位的Kronecker符號
- 一個有效的正交或雙正交小波族
我想/需要使用Gabor原子。
有人知道如何在wmpdictionary中使用Gabor或者定製新種類的原子嗎？
------------------最終解決------------------ 那麼我找到了一個公式Gabor原子在紙上[1]。 我生成使用這些函數的字典：
function atom = getGaborAtom(N,scale,timeShift,frequency,phase)
%This function obtains a Gabor atom of given parameters
%N- Length of the signal
%scale- must be in number of samples
%timeShift - must be in number of samples
%frequency - its normalized frequency from 0 to 0.5 f/fs;
%Phase - a value from 0 to 2 pi
%This version uses the number of samples but seconds can also be used.
atom =zeros(N,1);
for n=1:N
atom(n,1) = (1/sqrt(scale))*exp(-pi*(n-timeShift)^2/scale^2) * cos(2*pi*frequency* (n-timeShift)+phase);
end
atom = (1/norm(atom)) .* atom; %Normalization
end
function [dictionary parameters]=constructDictionaryGabor()
%Construct a Gabor dictionary
%parameters are scale timeshift and frequency
N=256; %Size of the atom
scales = [2^1 2^2 2^3 2^4]; %More scales can be added
freqs = [0 .001 .002 .05 .1 .2 .3 .4 .5]; % f/fs normalized frequency. More freqs can be added
timeShifts = [0 64 128]; %More time shifts can be added
phase =0; %More phase values can be added, here I'm fixinf phase to 0
dictionary = zeros(N,length(scales)*length(freqs)*length(timeShifts)*length(phase));
parameters = zeros(3,length(scales)*length(freqs)*length(timeShifts)*length(phase);
contador = 1;
for t=1:length(timeShifts)
for f=1:length(freqs)
for s=1:length(scales)
dictionary(:,contador) = getGaborAtom(N,scales(s),timeShifts(t),freqs(f),phase);
parameters(:,contador) = [scales(s) timeShifts(t) freqs(f)];
contador = contador+1;
end
end
end
end
該字典可以用函數wmpdictionary使用，基質parameteres具有每每個原子的參數。
[1]環境聲音識別隨着時間頻率的音頻特性