OCR licence plate detection using matlab

[magvitron]

function for determining the band of letters

[CODE]function output = recognitionLetter (inputCropImg)
image = rgb2gray((inputCropImg));
subplot(1,2,1) | imshow(image);
%figure = imshow(image);
%image=imread(image);
%url = 'http://10.10.1.2:8080/shot.jpg';
%ss  = imread(url);

%fh = ss(ss);
%while(1)
%ss  = imread(url);
% set(fh,'CData',ss);
%drawnow;
%end

%impimg=imresize(image,[300 600]);%------resize the image to 600x300-------
%grimg=rgb2gray(impimg);
gradj=imadjust(image);
gradj2=medfilt2(gradj,[2 2]);
ejdet=edge(gradj2,'sobel',[],'vertical');
%imshow(ejdet);
[imy,imx]=size(gradj2);
%disp(imx);
%disp(imy);
%imshow(gradj2);
%imx=width/number of columns
%imy=height/number of rows
mn=[10 20];
se=strel('rectangle',mn);
ejdet=imdilate(ejdet,se);
vert=mean(ejdet,1);     %mean of columns gives a row with values of all columns
horz=mean(ejdet,2);     %mean of rows gives a column with values of all rows
h = fspecial('average', 20);
g = fspecial('average', 200);
horz=filter2(g,horz);
vert=filter2(g,vert);
%subplot(1,2,1)|plot(horz);subplot(1,2,2)|plot(vert);
for i=1:imy
    if(horz(i)<0.000050)
        horz(i)=0;
        %  else
        %      horz(i)=1;
    end
end
for i=1:imx
    if(vert(i)<0.000100)
        vert(i)=0;
    end
end

mask=zeros(imy,imx);
for i=1:imy
    if(horz(i)~=0)
        mask(i,:)=1;
    end
end
mask2=zeros(imy,imx);
for j=1:imx
    if(vert(j)~=0)
        mask2(:,j)=1;
    end
end

for i=1:imy
    if(horz(i)~=0)
        gradj2(~mask)=0;
    end
end

for i=1:imx
    if(vert(i)~=0)
        gradj2(~mask2)=0;
    end
end
bwimg=im2bw(gradj2);
bwn=imfill(bwimg,[1 1],8);      %fills the background
bwn=~bwn;%complements the image   if(vert(i)~=0)


bwop=bwareaopen(bwn,500);   %remove small objects less than 500 pixels
%se=strel('disk',5);
%bwer=imerode(bwn,se);
subplot(1,2,2) | imshow(bwop);
%----------------segmentation starts-----------
stats = regionprops(bwop);          %computes area boundingbox and centroid of the image according to the area of regions
len=size(stats,1);
index1 = 1;
for index=1:length(stats)
    if stats(index).Area > 400 && stats(index).BoundingBox(3)*stats(index).BoundingBox(4) < 30000;   %checks the image to segment
        
        x=ceil(stats(index).BoundingBox(1));
        y=ceil(stats(index).BoundingBox(2));
        widthX=floor(stats(index).BoundingBox(3)-1);
        widthY=floor(stats(index).BoundingBox(4)-1);
        subimage(index1)={bwop(y:y+widthY,x:x+widthX)};
        a(index1)=subimage(index1);
        index1 = index1+1;
        %figure,imshow(a{index});
    else
         a(index1)=subimage(index1);
    end
end

%********************OCR(Optical Character Recognition)*****************
len=size(a,2);
%len =10;
load templates;
global templates;

% disp(size(templates));
num_of_leters=35;

% disp(num_of_leters);
%Opens text.txt as file for write
fid = fopen('text1.txt', 'a');
word=[ ];
comp=[ ];
for i=1:len
    img_r=imresize((a{i}),[42 24]);
    letters=read_letter(img_r,num_of_leters);    %convert the image to text
    word=[word letters];    %concatenate the letters
end

output = word;
fprintf(fid,'\r\n %s \n\r',word);   %Write 'word' in text file (upper)
disp(text.txt);  % print the most prominent character in the text file
%close the file
fclose(fid);
%Open 'text.txt' file
% winopen('text.txt');

read letter
function letter=read_letter(img_r,num_of_leters)
% Computes the correlation between template and input image
% and its output is a string containing the letter.
% Size of 'imagn' must be 42 x 24 pixels
% Example:
% imagn=imread('D.bmp');
% letter=read_letter(imagn)
global templates
comp=[ ];
%img_r=imread('/letters_numbers/0.bmp');
%num_of_leters=size(templates,2);
for n=1:num_of_leters
    sem=corr2(img_r,templates{1,n});
    comp=[comp sem];
end
%compmax=max(comp);
%for i=1:num_of_leters
%	if(comp(i)==compmax)
%		vd=i;
%	end
%end
% disp(comp);
vd=find(comp==max(comp));
%*-*-*-*-*-*-*-*-*-*-*-*-*-
if vd==27
    letter='1';
elseif vd==28
    letter='2';
elseif vd==29
    letter='3';
elseif vd==30
    letter='4';
elseif vd==31
    letter='5';
elseif vd==32
    letter='6';
elseif vd==33
    letter='7';
elseif vd==34
    letter='8';
elseif vd==35
    letter='9';
elseif vd==36
    letter='0';
elseif vd==1
    letter='A';
elseif vd==2
    letter='B';
elseif vd==3
    letter='C';
elseif vd==4
    letter='D';
elseif vd==5
    letter='E';
elseif vd==6
    letter='F';
elseif vd==7
    letter='G';
elseif vd==8
    letter='H';
elseif vd==9
    letter='I';
elseif vd==10
    letter='J';
elseif vd==11
    letter='K';
elseif vd==12
    letter='L';
elseif vd==13
    letter='M';
elseif vd==14
    letter='N';
elseif vd==15
    letter='O';
elseif vd==16
    letter='P';
elseif vd==17
    letter='Q';
elseif vd==18
    letter='R';
elseif vd==19
    letter='S';
elseif vd==20
    letter='T';
elseif vd==21
    letter='U';
elseif vd==22
    letter='V';
elseif vd==23
    letter='W';
elseif vd==24
    letter='X';
elseif vd==25
    letter='Y';
elseif vd==26
    letter='Z';
else
    letter='err';
    %*-*-*-*-*
end