非均匀性矫正

一、图像的非均匀性矫正

二、图像增强

三、程序代码（MATLAB）%%%%%%%%%%%%%%%%%%%%555555555555555555555555555555555一点矫正HIGH_T=fopen('highdat_151.dat','rb');

HIGH=fread(HIGH_T,[200,200],'uint8');

HIGH=uint8(HIGH); %类型转化为uint8

subplot(321);imshow(HIGH); title('原始高温图像');

subplot(322);mesh(double(HIGH));title('原始高温图像三维显示'); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

LOW_T=fopen('lowdat_151.dat','rb');

LOW=fread(LOW_T,[200,200],'uint8');

LOW=uint8(LOW);

subplot(323);imshow(LOW); title('原始低温图像');

subplot(324);mesh(double(LOW)); title('原始低温图像三维显示'); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

HAND_D=fopen('handdat_60.dat','rb');

HAND=fread(HAND_D,[200,200],'uint8');

HAND=uint8(HAND);

subplot(325),imshow(HAND); title('原始手形图像');

subplot(326),mesh(double(HAND)); title('原始手形图像三维显示'); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%选取低温图进行定标

S=mean2(LOW(:)); % S为定标值

S_LOW=S*ones(200,200);

S_LOW=uint8(S_LOW); %S_LOW为定标矩阵

D_LOW=LOW-S_LOW; %校正系数D_LOW

figure;

HIGH_L=HIGH-D_LOW;

subplot(321);imshow(HIGH_L); title('经低温矫正后的高温图像');

subplot(322);mesh(double(HIGH_L)); title('经低温矫正后的高温图像三维显示'); LOW_L=S_LOW;

subplot(323);imshow(LOW_L); title('经低温矫正后的低温图像');

subplot(324);mesh(double(LOW_L)); title('经低温矫正后的低温图像三维显示'); HAND_L=HAND-D_LOW;

subplot(325);imshow(HAND_L); title('经低温矫正后的原始手图像');

subplot(326);mesh(double(HAND_L)); title('经低温矫正后的原始手图像三维显示'); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%选取高温图进行定标

S=mean2(HIGH(:)); % S为定标值

S_HIGH=S*ones(200,200);

S_HIGH=uint8(S_HIGH); %S_LOW为定标矩阵

D_HIGH=HIGH-S_HIGH; %校正系数D_HIGH

figure;

HIGH_H=S_HIGH;

subplot(321);imshow(HIGH_H); title('经高温矫正后的高温图像');

subplot(322);mesh(double(HIGH_H)); title('经高温矫正后的高温图像三维显示'); LOW_H=LOW-D_HIGH;

subplot(323);imshow(LOW_H); title('经高温矫正后的低温图像');

subplot(324);mesh(double(LOW_H)); title('经高温矫正后的低温图像三维显示'); HAND_H=HAND-D_HIGH;

subplot(325);imshow(HAND_H); title('经高温矫正后的原始手图像');

subplot(326);mesh(double(HAND_H)); title('经高温矫正后的原始手图像三维显示');

%%%%%%%%5555555555555555555555555555555555555555两点矫正%%%%%在上述程序基础之上

S_L=mean2(LOW(:)); % S_L为矫正点定标值

S_H=mean2(HIGH(:)); % S_H为矫正点定标值

G_1=S_H-S_L; %数G_1

G_2=HIGH-LOW; %矩阵G_2

G=zeros(200,200);

figure;

G_3=zeros(200,200);

O=zeros(200,200);

HIGH_HL=zeros(200,200);

for x=1:200

for y=1:200

G(x,y)=G_1/G_2(x,y);%乘性增益

G_3(x,y)=G(x,y)*LOW(x,y);

O(x,y)=S_L-G_3(x,y); %加性增益

HIGH_HL(x,y)=HIGH(x,y)*G(x,y)+O(x,y);%对盲元处进行矫正end

end

HIGH_HL=uint8(HIGH_HL);

subplot(321); imshow(HIGH_HL,[]);title('两点矫正后的高温图像');

subplot(322);mesh(double(HIGH_HL)); title('两点矫正后的高温图像三维显示'); LOW_HL=zeros(200,200);

for x=1:200

for y=1:200

G(x,y)=G_1/G_2(x,y);%乘性增益

G_3(x,y)=G(x,y)*LOW(x,y);

O(x,y)=S_L-G_3(x,y); %加性增益

LOW_HL(x,y)=LOW(x,y)* G(x,y)+O(x,y);%对盲元处进行矫正

end

end

LOW_HL=uint8(LOW_HL);

subplot(323);imshow(LOW_HL,[]); title('两点矫正后的低温图像');

subplot(324);mesh(double(LOW_HL)); title('两点矫正后的低温图像三维显示'); HAND_HL=zeros(200,200);

for x=1:200

for y=1:200

G(x,y)=G_1/G_2(x,y);%乘性增益

G_3(x,y)=G(x,y)*LOW(x,y);

O(x,y)=S_L-G_3(x,y); %加性增益

HAND_HL(x,y)=HAND(x,y)* G(x,y)+O(x,y);%对盲元处进行矫正end

end

HAND_HL=uint8(HAND_HL);

subplot(325);imshow(HAND_HL,[]); title('两点矫正后的手图像');

subplot(326);mesh(double(HAND_HL)); title('两点矫正后的手图像三维显示');

%%%%%%%%%%%%%%%%%%%%%%%%%%%%直方图均衡增强

TU=HAND_HL;

graydis=zeros(1,256); %设置矩阵大小

graydispro=zeros(1,256);

new_graydis=zeros(1,256);

new_graydispro=zeros(1,256);

[N,M]=size(TU);

NEW_TU=zeros(N,M);

for x=1:N

for y=1:M

graydis(1,TU(x,y))=graydis(1,TU(x,y))+1;

end

end

graydispro=graydis./sum(graydis);

for i=2:256

graydispro(1,i)=graydispro(1,i)+graydispro(1,i-1);

end

%计算和原始灰度对应的新的灰度t[]，建立映射关系

for i=1:256

t(1,i)=floor(254*graydispro(1,i)+0.5);

end

for x=1:N

for y=1:M

NEW_TU(x,y)=t(1,TU(x,y));

end

end

%%%%%%%%%%%%%%%%%%%%5555555555555555555改进图像增强算法I=TU;

m=mean(I(:));%获得图像阈值

for i=1:200

for j=1:200

if I(i,j)>m+2 && I(i,j)<=255 %灰度大于阈值灰度按一定比值进行增加l=I(i,j)-m; %灰度差值

k=20*l/(255-m); %%灰度增加量

I1(i,j)=I(i,j)+k;

else

I1(i,j)=I(i,j)-80; %灰度小于阈值，灰度减小

end

end

end

s=fftshift(fft2(I1));

[a,b]=size(s);

a0=round(a/2);

b0=round(b/2);

d=0.001;

p=0.9;q=1;

for i=1:a

for j=1:b

distance=sqrt((i-a0)^2+(j-b0)^2);

if distance<=d

h=0;

else

h=1;

end

s(i,j)=(p+q*h)*s(i,j);

end

end

s=uint8(real(ifft2(ifftshift(s)))); figure;

subplot(321);imshow(TU,[]);

title('两点矫正后的手图');

subplot(322);mesh(double(TU));

title('对应的三为响应图');

subplot(323);imshow(NEW_TU,[]); title('直方图均衡化后的图'); subplot(324);mesh(double(NEW_TU)); title('对应的三为响应图');

subplot(325);imshow(s,[]);

title('算法增强后所得图像'); subplot(326);mesh(double(s));

title('对应三维响应图');