wave2.m

来自「一个关于JEPG2000的MATLAB 源码」· M 代码 · 共 32 行

function wave2
X=imread('GIRL.BMP');
X=gray2ind(X);
%X=ind2gray(X,map);
% The current extension mode is zero-padding (see dwtmode).
%load woman;
%figure(1);
% Load original image. 
%I=load woman; 
% X contains the loaded image.
%imshow(X);
%X=ind2gray(X);
subplot(131);image(X);%colormap(map);
% Perform decomposition at level 2 
% of X using db1. 
%imshow(X)

[c,s] = wavedec2(X,2,'db3');

% Decomposition structure organization. 
sizex = size(X)
[thr,sorh,keepapp]=ddencmp('cmp','wv',X);
[Xcomp,cxc,lxc,perf0,perfl2]=wdencmp('gbl',c,s,'db3',5,thr,sorh,keepapp);%将压缩后的图像与原始图像相比较
%Xcomp=ind2gray(Xcomp);
subplot(133);image(Xcomp);%colormap(map);
title('DWT压缩后的图像');
axis square
disp('小波分解系数中置0的系数个数百分比：');
perf0
disp('压缩后图像剩余能量百分比：');
perfl2