Page 175 - Algorithm Collections for Digital Signal Processing Applications using MATLAB

164 Chapter 4

wavelet.m

function [res]=wavelet(x)
x=double(x);
[c,l]=wavedec2(x,1,'db6');
a=appcoef2(c,l,'db6',1);
v1=var(reshape(a,1,size(a,1)*size(a,2)));
d1=detcoef2('h',c,l,1);
v2=var(reshape(d1,1,size(d1,1)*size(d1,2)));
d2=detcoef2('v',c,l,1);
v3=var(reshape(d2,1,size(d2,1)*size(d2,2)));
d3=detcoef2('d',c,l,1);
v4=var(reshape(d3,1,size(d3,1)*size(d3,2)));
res=[v1 v2 v3 v4];

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skew.m

function [res]=skew(x)
x=double(x);
z=reshape(x,1,size(x,1)*size(x,2));
h=hist(double(z),256);
h=h/sum(h);
m=mean(z);
res=sum(((z-m).^3).*h(z+1));

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kurt.m

function [res]=kurt(x)
x=double(x);
z=reshape(x,1,size(x,1)*size(x,2));
h=hist(double(z),256);
h=h/sum(h);
m=mean(z);
res=sum(((z-m).^4).*h(z+1));

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