How to extract the plate area only from black background

Hi, i want to know how to crop the plate area only from the image shown below my code takes the RGB image & outputs this image, so i need only a way to extract the numbers area only here is the output picture

thanks in advance

Answer 1

[Andrei Bobrov]

II=im2bw(I);
s=regionprops(II,'Area','BoundingBox');
[ii,ii] = sort([s.Area],'descend');
out = imcrop(I,s(ii(2)).BoundingBox);

[mohamed]

thanks for you all i did it at last thanks again but u must fix your code like this:

II=im2bw(I);
s=regionprops(II,'Area','BoundingBox');
[~,ii] = sort([s.Area],'descend');
out = imcrop(I,s(ii(1)).BoundingBox);

[Rinku]

thank you both of you..this code is help me very much..

Answer 2

[Image Analyst]

You could pass the image into regionprops() and ask for area and eccentricity. The plate will have a lower eccentricity than the lines, and probably but not necessarily a larger area than any/most/all of the lines. But I can't tell that that rectangular blob with a bunch of holes in it in the lower left is not also another license plate. At least for this one particular image, you could get rid of that based on area or FilledArea.

Answer 3

[Thomas]

The following thread might be helpful

http://www.mathworks.fr/matlabcentral/answers/4183-code-for-locating-lisence-plate