www.pudn.com > fractional-differential.rar > Enhance.m, change:2014-12-09,size:1690b

```%%%图像增强实验 ,不同大小Tiansi掩膜算子对比
close all
clear all
clc
imshow(I);
title('原图像');
I = im2double(I(:,:,1));
w1 = fspecial('laplacian',0);
I1 = imfilter(I,w1,'conv','replicate');
G1 = I-I1;
figure,imshow(G1);
title('Laplacian增强效果—1');   %Laplacian图像增强,未考虑对角线元素
w2 = [1 1 1;1 -8 1;1 1 1];
I2 = imfilter(I,w2,'conv','replicate');
G2 = I-I2;
figure,imshow(G2);
title('Laplacian增强效果—2');   %Laplacian图像增强，考虑对角线元素

%%
%分数阶微分
v = 0.8   % v代表分数阶微分的阶数
a0 = 1;
a1 = -v;
a2 = (-v)*(-v+1)/2;
a3 = (-v)*(-v+1)*(-v+2)/6;
a4 = (-v)*(-v+1)*(-v+2)*(-v+3)/24;
F1 = [a1 a1 a1 ;a1 8*a0 a1 ;a1 a1 a1]./(8-12*v+4*v*v);   % 3*3分数阶掩膜算子
F2 = [a2 0 a2 0 a2 ;0 a1 a1 a1 0 ;a2 a1 8*a0 a1 a2 ;...
0 a1 a1 a1 0 ;a2 0 a2 0 a2]./(8-12*v+4*v*v);        % 5*5分数阶掩膜算子
F3 = [a3 0 0 a3 0 0 a3 ;0 a2 0 a2 0 a2 0 ;0 0 a1 a1 a1 0 0 ;a3 a2 a1 8*a0 a1 a2 a3;...
0 0 a1 a1 a1 0 0 ;0 a2 0 a2 0 a2 0 ;a3 0 0 a3 0 0 a3]./(8-12*v+4*v*v);   % 7*7分数阶掩膜算子

% F1 = [v/(8*v-8),v/(8*v-8),v/(8*v-8);...
%                          v/(8*v-8),8/(8-8*v),v/(8*v-8);...
%                          v/(8*v-8),v/(8*v-8),v/(8*v-8)]; %另一种掩膜算子

% G_frac_1 = imfilter(I,F1,'conv','replicate');
% figure,imshow(G_frac_1,[]);
% title(['3*3分数阶掩膜算子',' 阶数',num2str(v),'阶']);

G_frac_2 = imfilter(I,F2,'conv','replicate');
figure,imshow(G_frac_2,[]);
title(['5*5分数阶掩膜算子',' 阶数',num2str(v),'阶']);

% G_frac_3 = imfilter(I,F3,'conv','replicate');
% figure,imshow(G_frac_3,[]);
% title(['7*7分数阶掩膜算子',' 阶数',num2str(v),'阶']);

```