how to draw a rectangle to identify character

This code to draw a rectangle to identify character that I had found (overlay the template in a target).

[name,path] = uigetfile('*.jpg');
image1 = imread([path,name]);
[name,path] = uigetfile('*.jpg');
image2 = imread([path,name]);

if size(image1,3)==3
    image1=rgb2gray(image1);
end
if size(image2,3)==3
    image2=rgb2gray(image2);
end

% check which one is target and which one is template using their size

if size(image1)>size(image2)
    Target=image1;
    Template=image2;
else
    Target=image2;
    Template=image1;
end

% find both images sizes
[r1,c1]=size(Target);
[r2,c2]=size(Template);
% mean of the template
image22=Template-mean(mean(Template));

%corrolate both images

corrMat=[];
for i=1:(r1-r2+1)
    for j=1:(c1-c2+1)
        Nimage=Target(i:i+r2-1,j:j+c2-1);
        Nimage=Nimage-mean(mean(Nimage));  % mean of image part under mask
        corr=sum(sum(Nimage.*image22));
        corrMat(i,j)=corr;
    end 
end

[Image Analyst]

http://www.mathworks.com/matlabcentral/answers/13205-tutorial-how-to-format-your-question-with-markup

Answer 1

[Image Analyst]

That's a dangerous way to use size(). Looks like someone needs to read Steve's blog on the use of the size function.

Anyway, I'm not sure what your question is. Do you want to draw a rectangle in the overlay above the image? If so, use plot() or rectangle().

[Image Analyst]

Anyway, you can't find a template in a target by correlation, at least not robustly. Think about it and if you don't know why, ask. You'll need to use normalized cross correlation, as shown in my attached demo.

[raha boolat]

It was a wonderful program. Bravo

Answer 2

[ahmed]

i want to draw a rectangle in a overlay the full image illuster to identify the character

[Image Analyst]

Invert your image so that the letters are white and then run the normalized cross correlation code I gave you.

Answer 3

[raha boolat]

function obj_det(img_name)
f=imread (img_name);
if (size(f,3) >1)
    f=rgb2gray(f);
    f_bw=~im2bw(f,graythresh(f));
else
    f_bw=~im2bw(f,graythresh(f));
end
f_bw=imfill(f_bw,'holes');
s=bwconncomp(f_bw);
imshow(f);
for i=1:s.NumObjects
    ind=s.PixelIdxList{i};
    [r,c]=ind2sub(size(f),ind);
    min_r=min(r,[],1);
    max_r=max(r,[],1);
    min_c=min(c,[],1);
    max_c=max(c,[],1);
    hy=max_r - min_r;
    hx=max_c - min_c;
    rectangle('position',[min_c,min_r,hx,hy],'EdgeColor','r');
end
end

[Rik]

@raha boolat This time I edited your answer for you. Next time, please use the tools explained on this page to make your posts more readable.