yuan.m

现在有很多相机类型

function [X0,Y0,R]=Yuan(rgb)  %定义函数，获得圆形区域的圆心坐标及半径
r=rgb(:,:,1);
g=rgb(:,:,2);
b=rgb(:,:,3);
I=0.59*r+0.11*g+0.3*b; %像素亮度计算公式
I=uint8(I);
[Height,Width]=size(I);
Thre=46;  %预设阈值

for Row1=1:(Height/2);  %循环寻找圆形区域上边界  

    CurRow_Bright=I(Row1,:);
    Max=max(CurRow_Bright); %求取最大亮度值
    Min=min(CurRow_Bright); %求取最小亮度值
    Lim=Max-Min;  %该扫描线的极限亮度差
     if (Lim>Thre),
         Ytop=Row1;
         break;
     end
     
end
     
for Row2=Height:-1:(Height/2);  %循环寻找圆形区域下边界  
    
    CurRow_Bright=I(Row2,:);
    Max=max(CurRow_Bright); %求取最大亮度值
    Min=min(CurRow_Bright); %求取最小亮度值
    Lim=Max-Min;  %该扫描线的极限亮度差
     if (Lim>Thre)
         Ybot=Row2;
         break;
     end
     
end
 
for Col1=1:(Width/2);  %循环寻找圆形区域左边界  
   
    CurCol_Bright = I(:,Col1);
    Max=max(CurCol_Bright); %求取最大亮度值
    Min=min(CurCol_Bright); %求取最小亮度值
    Lim=Max-Min;  %该扫描线的极限亮度差
     if (Lim>Thre),
         Xleft=Col1;
         break;
     end
     
end

for Col2=Width:-1:Width/2;  %循环寻找圆形区域右边界  
   
    CurCol_Bright = I(:,Col2);
    Max=max(CurCol_Bright); %求取最大亮度值
    Min=min(CurCol_Bright); %求取最小亮度值
    Lim=Max-Min;  %该扫描线的极限亮度差
     if (Lim>Thre),
         Xrig=Col2;
         break;
     end
         
end

X0=(Xleft+ Xrig)/2;
Y0=(Ytop+Ybot)/2;
Rx=floor((Xrig-Xleft)/2);
Ry=floor((Ytop-Ybot)/2);
R=max(Rx,Ry);
% 
% rgb(Ytop,Xleft:Xrig,1)=255;
% rgb(Ytop,Xleft:Xrig,2)=0;
% rgb(Ytop,Xleft:Xrig,3)=0;
% 
% rgb(Ybot,Xleft:Xrig,1)=255;
% rgb(Ybot,Xleft:Xrig,2)=0;
% rgb(Ybot,Xleft:Xrig,3)=0;
% 
% rgb(Ytop:Ybot,Xleft,1)=255;
% rgb(Ytop:Ybot,Xleft,2)=0;
% rgb(Ytop:Ybot,Xleft,3)=0;
% 
% rgb(Ytop:Ybot,Xrig,1)=255;
% rgb(Ytop:Ybot,Xrig,2)=0;
% rgb(Ytop:Ybot,Xrig,3)=0;
% 
% figure,imshow(rgb);