使用Gabor或自定义原子的MATLAB Matching Pursuit wmpdictionary

本文介绍了使用Gabor或自定义原子的MATLAB Matching Pursuit wmpdictionary的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我正在使用MATLAB 2013，现在包括Matching Pursuit算法.它具有一个称为 wmpdictionary 的功能，用于创建字典.据我所知，能够使用下一个函数在字典中创建原子:

I'm using MATLAB 2013 which now includes Matching Pursuit algorithm. It has a function called wmpdictionary for creating a dictionary. As far as I know is capable of using the next functions to create atoms in the dictionary:

离散余弦变换II基础
正弦波
余弦
多项式
转移的克罗内克三角洲
有效的正交或双正交小波族

我想/需要使用 Gabor 原子.

有人知道如何在wmpdictionary中使用Gabor或另选一种自定义新型原子的方法吗?

Does someone knows how to use Gabor in wmpdictionary or alternatively a way to customize new kinds of atoms?.

------------------最终解决了------------------好吧，我在论文中找到了一个Gabor原子的公式[1].我使用以下功能生成了字典:

------------------FINALLY SOLVED------------------Well I found a formula for Gabor atoms in the paper [1].I generated a dictionary using these functions:

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

此字典可与wmpdictionary函数一起使用，矩阵参数具有每个原子的参数.

This dictionary can be used with the function wmpdictionary, the matrix parameteres has the parameters per each atom.

[1]具有时频音频功能的环境声音识别

[1] Environmental Sound Recognition With Time–Frequency Audio Features

wmpdictionary

使用Gabor或自定义原子的MATLAB Matching Pursuit wmpdictionary

问题描述

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