PDF417码解码程序（MATLAB代码）

%%读取符号字符集 load symcodes.mat -ascii %%读取图像 src = imread('2.bmp'); %%取图像的R分量 src = src(:,:,1); %figure,imshow(src) %%二值化 src = (src > 160) * 255; [row,col]=size(src) %figure,imshow(src); %%旋转 %寻找左侧边线 leftline=zeros(row,2); k=1; for i=int16(row/3):row for j=1:col if src(i,j) <= 50 if k == 1 leftline(k,1) = i; leftline(k,2) = j; k = k+1; else if abs(j-leftline(k-1, 2)) < 10 leftline(k,1) = i; leftline(k,2) = j; k = k+1; end end break end end end %描左侧线 %ltl=leftline'; %plot(ltl(2,1:k)); %计算tan值数组 n = int16(k/2); tanarray=zeros(n,1); for i=1:n tanarray(i) = (leftline(i+n, 2)-leftline(i, 2))/(leftline(i+n, 1)-leftline(i, 1)); end tanarray=sort(tanarray); %自带函数旋转图像 % ang=atan(0-tanarray(int16(n/2)))*180/pi % ost=imrotate(src, ang, 'nearest', 'crop'); %figure,imshow(ost); %手动旋转 % ang=atan(0-tanarray(int16(n/2))) % sinang = sin(ang); % cosang = cos(ang); % new_row = round(col*sinang + row*cosang) % new_col = round(col*cosang + row*sinang) % ost = ones(new_row, new_col)*255; % for i=1:row % for j=1:col % xx = round(abs((i-row/2)*cosang-(j-col/2)*sinang+new_row/2)); % yy = round(abs((i-row/2)*sinang+(j-col/2)*cosang+new_col/2)); % ost(xx,yy)=src(i,j); % end % end % figure,imshow(ost); ang=atan(tanarray(int16(n/2)))*180/pi ost=imagerotate(src,ang,0); ost=double(ost); [new_row,new_col]=size(ost); %旋转后横向插值 for i=1:new_row for j=1:new_col-2 if ((ost(i,j)==0)&&(ost(i,j+2)==0)&&(ost(i,j+1)==255)) ost(i,j+1)=0; end if ((ost(i,j)==255)&&(ost(i,j+2)==255)&&(ost(i,j+1)==0)) ost(i,j+1)=255; end end end %旋转后纵插值 for i=1:new_col for j=1:new_row-2 if ((ost(j,i)==0)&&(ost(j+2,i)==0)&&(ost(j+1,i)==255)) ost(j+1,i)=0; end if ((ost(j,i)==255)&&(ost(j+2,i)==255)&&(ost(j+1,i)==0)) ost(j+1,i)=255; end end end for i=1:new_col for j=3:new_row-3 if ((ost(j-2,i)==0)&&(ost(j-1,i)==0)&&(ost(j,i)==255)&&(ost(j+1,i)==255)&&(ost(j+2,i)==0)&&(ost(j+3,i)==0)) ost(j,i)=0; ost(j+1,i)=0; end end end %figure,imshow(ost); %%切割出条码范围 %先找上下边线 hvalues=sum(ost'); %figure,plot(hvalues); T=new_col*255/1.45 for i=2:new_row-5 if (hvalues(i-1)>T) && (hvalues(i)<T) && (hvalues(i+1)<T) && (hvalues(i+2)<T) && (hvalues(i+3)<T) && (hvalues(i+4)<T) && (hvalues(i+5)<T) topedge=i; break; end end for i=topedge:new_row-3 if (hvalues(i-1)<T) && (hvalues(i)<T) && (hvalues(i+1)>T) && (hvalues(i+2)>T) && (hvalues(i+3)>T) botedge=i; break; end end topedge botedge %由上边线寻找左上角端点 midpit=round((topedge+botedge)/2) for j=3:new_col-5 if (ost(midpit,j-2)>200) && (ost(midpit,j-1)>200) && (ost(midpit,j)<10) && (ost(midpit,j+1)<10) && (ost(midpit,j+2)<10) && (ost(midpit,j+3)<10) && (ost(midpit,j+4)<10) x1=topedge; y1=j; break; end end %由下边线寻找右下角 for j=new_col-5:-1:y1+1 if (ost(midpit,j+5)>200) && (ost(midpit, j+4)>200) && (ost(midpit, j+3)>200) && (ost(midpit, j+2)>200) && (ost(midpit,j+1)>200) && (ost(midpit,j)<10) && (ost(midpit,j-1)<10) x2=botedge; y2=j; break; end end % %由上边线寻找左上角端点 % for j=2:new_col-5 % if (ost(topedge,j-1)>200) && (ost(topedge,j)<10) && (ost(topedge,j+1)<10) && (ost(topedge,j+2)<10) && (ost(topedge,j+3)<10) && (ost(topedge,j+4)<10) && (ost(topedge+2,j+2)<10) && (ost(topedge+3,j+3)<10) % x1=topedge; % y1=j; % break; % end % end % %由下边线寻找右下角 % for j=y1+1:new_col-5 % if (ost(botedge-1,j-1)<10) && (ost(botedge-1,j)<10) && (ost(botedge,j+1)>200) && (ost(botedge,j+2)>200) && (ost(botedge,j+3)>200) && (ost(botedge,j+4)>200) && (ost(botedge+2,j+2)>200) && (ost(botedge+3,j+3)>200) % x2=botedge; % y2=j; % end % end %分离条码图像 ost = ost(x1:x2,y1:y2); [row,col]=size(ost); figure,imshow(ost) %%边缘检测 src = ost; %边缘检测算子 topso=[1 1 1;0 0 0;-1 -1 -1]; botso=[-1 -1 -1;0 0 0;1 1 1]; lefso=[1 0 -1;1 0 -1;1 0 -1]; rigso=[-1 0 1;-1 0 1;-1 0 1]; for i=2:row-1 for j=2:col-1 temp=src(i-1:i+1,j-1:j+1); tbs =abs(sum(sum(topso.*temp))); lrs =abs(sum(sum(lefso.*temp))); if (tbs==0) && (lrs==0) ost(i,j)=255; end end end %figure,imshow(ost); %%消除垂直边缘 src = ost; dst = ost; for j=1:col for i=1:row-1 if src(i+1,j)==src(i,j) dst(i,j)=255; end end end %figure,imshow(dst); %%判断数据码字行数 [row,col]=size(ost); obs = (dst==0); rows= sum(obs,2); %figure,plot(rows); rowtvalue=round(col/20); line=zeros(1,row); k=0; for i=4:row-3 if (rows(i)>rows(i-1)) && (rows(i)>rows(i-2)) && (rows(i)>rows(i-3)) && (rows(i)>rows(i+1)) && (rows(i)>rows(i+2)) && (rows(i)>rows(i+3)) && (rows(i)>rowtvalue) k=k+1; line(k)=i; end end k line=line(1:k) %%消除水平边缘 dst = ost; for i=1:row for j=2:col if src(i,j-1)==src(i,j) dst(i,j)=255; end end end ost = (dst==255); figure,imshow(ost); %%提取码字 linst=zeros(1,k+1); linst(1)=round(line(1)/2); for i=1:k-1 linst(i+1)=round((line(i)+line(i+1))/2); end linst(k+1)=round((line(k)+row)/2); %linst minst=zeros(1,k+1); codes=zeros(k+1,col); for i=1:k+1 m=0; for j=2:col if ost(linst(i),j)==0 if m==0 m=m+1; codes(i,m)=j; temp=j; else m=m+1; codes(i,m)=j-temp; temp=j; end minst(i)=m; end end end asum=0; for i=1:k+1 asum=asum+codes(i,1); end aunit = round(asum/(k+1)/8) acodes= zeros(k+1,minst(1)); for i=1:k+1 for j=1:minst(1) acodes(i,j)=round(codes(i,j)/aunit); end end acodes %转换符号码字为待解码码字（符号码字 到 数字码字） [row,col] = size(acodes); acodes = acodes(:,17:col-17); [row,col] = size(acodes); dcodes = zeros(1, round(row*col/8)); k = 0; for i=1:row for j=1:8:col temp = acodes(i,j)*10000000 + acodes(i,j+1)*1000000 + acodes(i,j+2)*100000 + acodes(i,j+3)*10000 + acodes(i,j+4)*1000 + acodes(i,j+5)*100 + acodes(i,j+6)*10 + acodes(i,j+7); for m=1:3 for n=1:929 if symcodes(m,n)==temp k=k+1; dcodes(k)=n-1; break; end end end end end dcodes %%解码 %文本模式码表TC,码表里的值是Ascii值，之所以不直接存成字符，是因为有些Ascii值无法显示，比如LF、CR等 %将模式转换符号定义成数值,如下： %ll=201，锁定为小写字母模式 %ml=202，锁定为混合模式 %pl=203，锁定为标点模式 %al=200，锁定为大写字母模式 %ps=204，转移为标点模式 %as=205，转移为大写字母模式 tc_uc=[65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,32,201,202,204];%大写字母模式 tc_lc=[97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,32,205,202,204];%小写字母模式 tc_mi=[48,49,50,51,52,53,54,55,56,57,38,13,09,44,58,35,45,46,36,47,43,37,42,61,94,203,32,201,200,204];%混合型模式 tc_do=[59,60,62,64,91,92,93,95,96,126,33,13,09,44,58,10,45,46,36,47,34,124,42,40,41,63,123,125,39,200];%标点型模式 %数字模式码表 nc_tb=[48,49,50,51,52,53,54,55,56,57]; %开始解码，暂时不支持字节型模式，只支持文本模式和数字模式 codelen=dcodes(1); mode=11;%2->数字型、3->字节型、11->文本模式大写型、12->文本模式小写型、13->文本模式混合