基于MATLAB的图片中字符的提取(源代码)

1、基于MATLAB的图片中字符的提取（源代码）function getPicChar %建立字符提取函数，在MATLAB平台上直接运行即可%运用MATLAB的UI，直接打牌需要提取的字符图片即可filename, pathname,=uigetfile('*.jpg''*.bmp''*.png','Chose a picture');picstr=pathname filename;if ischar(picstr) return;endpic=imread(picstr); %打开图片 if length(size(pic)=3

2、%判断图片的维数，统一为灰度图片 pic=rgb2gray(pic);endpic=(pic<127); %转化为二值图片 pic=xylimit(pic); %图片区域的第一次边界限定 %第一阶段%m=size(pic,1);Ycount=zeros(1,m);for i=1:m Ycount(i)=sum(pic(i,:);endlenYcount=length(Ycount);Yflag=zeros(1,lenYcount);for k=1:lenYcount-2 if Ycount(k)<3 && Ycount(k+1)<3 && Yc

3、ount(k+2)<3 Yflag(k)=1; endendfor k=lenYcount:1+2 if Ycount(k)<3 && Ycount(k-1)<3 && Ycount(k-2)<3 Yflag(k)=1; endendYflag2=0 Yflag(1:end-1);Yflag3=abs(Yflag-Yflag2); %做差分运算,row=find(Yflag3=1); %找突变位置row=1 row m; %调整突变位置点row1=zeros(1,length(row)/2); %截取图像的起始位置向量row2=row1;

4、 %截取图像的终止位置向量for k=1:length(row) if mod(k,2)=1; %奇数为起始 row1(k+1)/2)=row(k); else %偶数为终止 row2(k/2)=row(k); endendpic2=pic(row1(1):row2(1),:); %截取第一列字符alpha=1024/size(pic2,2); %计算放缩比例pic2=imresize(pic2,alpha); %调整第一列字符图片大小，作为基准for k=2:length(row)/2 pictemp=imresize(pic(row1(k):row2(k),:),size(pic2,1)

5、size(pic2,2); pic2=cat(2,pic2,pictemp); %横向连接图像块endpic=xylimit(pic2); %限定图像区域 %第二阶段%,n=size(pic);Xcount=zeros(1,n);for j=1:n Xcount(j)=sum(pic(:,j);endlenXcount=length(Xcount);Xflag=zeros(1,lenXcount);for k=1:lenXcount-2 if Xcount(k)<3 && Xcount(k+1)<3 && Xcount(k+2)<3 Xflag

6、(k)=1; endendfor k=lenXcount:1+2 if Xcount(k)<3 && Xcount(k-1)<3 && Xcount(k-2)<3 Xflag(k)=1; endendXflag2=0 Xflag(1:end-1);Xflag3=abs(Xflag-Xflag2);,col=find(Xflag3=1);col=1 col size(pic,2);coltemp=col(2:end)-col(1:end-1);,ind=find(coltemp<3);col(ind)=0;col(ind+1)=0;col=

7、col(col>0);col1=zeros(1,length(col)/2);col2=col1;for k=1:length(col) if mod(k,2)=1 col1(k+1)/2)=col(k); else col2(k/2)=col(k); endendpicnum2=length(col)/2;piccell2=cell(1,picnum2);for k=1:picnum2 piccell2k=pic(:,col1(k):col2(k); piccell2k=xylimit(piccell2k); piccell2k=imresize(piccell2k,128 128);

8、end%显示提取出的字符，每行最多输出8个字符if mod(picnum2,8) rownum=ceil(picnum2/8)+1;else rownum=picnum2/8;endfor k=1:picnum2 subplot(rownum,8,k); imshow(piccell2k);end%函数xylimit如下：function newpic=xylimit(pic)%function name:XYLIMIT% Input pic:binary image%Output newpic:binary image%用途：对二值图像边界进行限定，要求图像是黑底白图%example:% %

9、 pic=imread('数字字符.jpg');% % pic=rgb2gray(pic);% % pic=(pic<127);% % pic=xylimit(pic);% % imshow(pic); m,n=size(pic);%纵向扫描%Ycount=zeros(1,m);for i=1:m Ycount(i)=sum(pic(i,:); %获取每一行的像素点个数endYbottom=m; %底部定界Yvalue=Ycount(Ybottom);while(Yvalue<3) Ybottom=Ybottom-1; Yvalue=Ycount(Ybottom);endYceil=1; %顶部定界Yvalue=Ycount(Yceil);while(Yvalue<3) Yceil=Yceil+1; Yvalue=Ycount(Yceil);end%横向扫描%Xcount=zeros(1,n);for j=1:n Xcount(j)=sum(pic(:,j); %获取每一列的像素点个数endXleft=1; %左侧定界Xvalue=Xcount(Xleft);while(Xvalue<2) Xleft=Xleft+1; Xvalue=Xcount(Xleft);endXright=n; %右侧定界Xvalue=Xcount(Xright);