matlab如何批量读取图片并作分析

本人小白，自己编了个代码，能把一张图片二值化，然后读取图中黑色区域的像素点数，但我想实现批量读取，然后处理的目的，求大神帮忙

I=imread('top051.bmp');
Zmax=max(max(I));
Zmin=min(min(I));
TK=(Zmax+Zmin)/2;%初始阈值
flag=1;
[m,n]=size(I);
while(flag)
fg=0;
bg=0;
fgsum=0;
bgsum=0;
for i=1:m
for j=1:n
tmp=I(i,j);
if(tmp>=TK)
fg=fg+1;
fgsum=fgsum+double(tmp);
else
bg=bg+1;
bgsum=bgsum+double(tmp);
end
end
end
u1=fgsum/fg;
u2=bgsum/bg;
TKTmp=uint8((u1+u2)/2);
if(TKTmp==TK)
flag=0;
else
TK=TKTmp;
end
end
BCT = sum(newI (:)==0)有可能的话，请好心朋友在这个基础上做些修改，已达到批量读取图片，并批量输出黑色区域像素点数的目的，在此谢过了，图片名称是由top001、top002、top003..........top452，这样的顺序编排的，请求详细答案，本人实在小白。。。。

for i=1:452
if i<10
str = ['top00',num2str(i),'.bmp'];
else if i<100
str = ['top0',num2str(i),'.bmp'];
else
str = ['top',num2str(i),'.bmp'];
end
I=imread(str);
Zmax=max(max(I));
Zmin=min(min(I));
TK=(Zmax+Zmin)/2;%初始阈值
flag=1;
[m,n]=size(I);
while(flag)
fg=0;
bg=0;
fgsum=0;
bgsum=0;
for i=1:m
for j=1:n
tmp=I(i,j);
if(tmp>=TK)
fg=fg+1;
fgsum=fgsum+double(tmp);
else
bg=bg+1;
bgsum=bgsum+double(tmp);
end
end
end
u1=fgsum/fg;
u2=bgsum/bg;
TKTmp=uint8((u1+u2)/2);
if(TKTmp==TK)
flag=0;
else
TK=TKTmp;
end
end
end

% 你的代码没有仔细看，有问题在说吧，结果在r中 n = 452; r = zeros(n,1); for p = 1:n     fn = ['000' num2str(p)];     fn = fn(length(fn)-1:end);     fn = ['top' fn '.bmp'];     i=imread(fn);     zmax=max(max(i));     zmin=min(min(i));     tk=(zmax+zmin)/2;%初始阈值     flag=1;     [m,n]=size(i);     while(flag)         fg=0;         bg=0;         fgsum=0;         bgsum=0;         for i=1:m             for j=1:n                 tmp=i(i,j);                 if(tmp>=tk)                     fg=fg+1;                     fgsum=fgsum+double(tmp);                 else                     bg=bg+1;                     bgsum=bgsum+double(tmp);                 end             end         end         u1=fgsum/fg;         u2=bgsum/bg;         tktmp=uint8((u1+u2)/2);         if(tktmp==tk)             flag=0;         else             tk=tktmp;         end     end     bct = sum(newi (:)==0);     r(p) = bct; end;