How to detect and crop boundry of the given image deleting unwanted space?

I want to crop the "Capture.JPG" image from "1.jpg"(left image=>right image)

I used the imcrop but it doesn't gave me the desired image.

My code is given below. Code requires two folders "Testing Images" and "Preprocess Testing Images".

code :-

Imges = dir('Testing Images\*jpg');

InputSet=[];

OutputSet=[];

for i = 1:numel(Imges)

 filename = strcat('Testing Images\',Imges(i).name); 
 I=imread(filename);
    Igray = rgb2gray(I);
    imwrite(Igray,strcat('Preprocessed Testing Images\GrayScale',int2str(i),'.jpg'));
    Ibw = im2bw(Igray,graythresh(Igray));
    imwrite(Ibw,strcat('Preprocessed Testing Images\Binary',int2str(i),'.jpg'));
    Ibwn=wiener2(Ibw,[5 5]);
    imwrite(Ibwn,strcat('Preprocessed Testing Images\AfterNoise',int2str(i),'.jpg'));
    Iedge = edge(Ibwn,'canny');
    imwrite(Iedge,strcat('Preprocessed Testing Images\AfterEdge()',int2str(i),'.jpg'));
    se = strel('arbitrary',2);
    Iedge2 = imdilate(Iedge, se);
    imwrite(Iedge2,strcat('Preprocessed Testing Images\AfterImdilate()',int2str(i),'.jpg'));
    Ifill= imfill(Iedge2,'holes');
    imwrite(Ifill,strcat('Preprocessed Testing Images\AfterImfill()',int2str(i),'.jpg'));
    IfillInvert=imcomplement(Ifill);
    imwrite(IfillInvert,strcat('Preprocessed Testing Images\AfterImInvert()',int2str(i),'.jpg'));
    Ifinal1 = bwareaopen(IfillInvert,100);

    [Ilabel num] = bwlabel(Ifinal1);
    Iprops = regionprops(Ilabel);
    Ibox = [Iprops.BoundingBox];      
    Icrop = imcrop(I,Ibox);
    imwrite(Icrop,strcat('Preprocessed Testing Images\AfterCrop1()',int2str(i),'.jpg'));

end

[Image Analyst]

What do you want? Only the white part, no green at all? Or you want a thin green boundary but it should be the same on the left edge as it is on the top, right, and bottom edges?

[Indunie Florence]

Actually I want to crop a piece of the card from top left corner to detect the suit. So I want to crop the card from margin.

[Image Analyst]

Well you accepted my solution below so I assume you're happy with the result.

[Indunie Florence]

yep. It gives the desired output.Thank you so much. Can you explain me please what I missed?

[Image Analyst]

I'm not sure - I didn't try it. Does it work too? There are sometimes several ways to accomplish something. I just saw some things that I wouldn't do, like edge detection, a bunch of imwrites, and stuff like that so I just did it the way I thought it should be done.

[Indunie Florence]

no, It doesn't crop above image correctly. Actually above code is a testing code for cropping. Your code is working to the given image by me. It is a very clear card. According to my target I use images with some noises. After some functions worked, it produces a image without boundary. I want to crop it too. Your code didn't work in this situation.

Can you help me.Image is given below. It is in binary mode.

[Image Analyst]

It's a different card so will require a different algorithm. Since it's not a green box, you need to invert the image, then call bwconvhull(), then bwlabeland regionprops, finally imcrop. Give it a try.

Answer 1

[Image Analyst]

Try the attached test.m file to produce this image.

[Ali Haider]

Hi,

I want to crop text in bounding box from an image. plz help me out in this.