Error in Iprops=reg​ionprops(f​inal,;Boun​dingBox','​Image')

    function numberPlateExtraction
    %NUMBERPLATEEXTRACTION extracts the characters from the input number plate image.

    f=imread('car3.jpg'); % Reading the number plate image.
    f=imresize(f,[400 NaN]); % Resizing the image keeping aspect ratio same.
    g=rgb2gray(f); % Converting the RGB (color) image to gray (intensity).
    g=medfilt2(g,[3 3]); % Median filtering to remove noise.
    se=strel('disk',1); % Structural element (disk of radius 1) for morphological processing.
    gi=imdilate(g,se); % Dilating the gray image with the structural element.
    ge=imerode(g,se); % Eroding the gray image with structural element.
    gdiff=imsubtract(gi,ge); % Morphological Gradient for edges enhancement.
    gdiff=mat2gray(gdiff); % Converting the class to double.
    gdiff=conv2(gdiff,[1 1;1 1]); % Convolution of the double image for brightening the edges.
    gdiff=imadjust(gdiff,[0.5 0.7],[0 1],0.1); % Intensity scaling between the range 0 to 1.
    B=logical(gdiff); % Conversion of the class from double to binary. 
    % Eliminating the possible horizontal lines from the output image of regiongrow
    % that could be edges of license plate.
    er=imerode(B,strel('line',50,0));
    out1=imsubtract(B,er);
    % Filling all the regions of the image.
    F=imfill(out1,'holes');
    % Thinning the image to ensure character isolation.
    H=bwmorph(F,'thin',1);
    H=imerode(H,strel('line',3,90));
    % Selecting all the regions that are of pixel area more than 100.
    final=bwareaopen(H,100);
    % final=bwlabel(final); % Uncomment to make compitable with the previous versions of MATLAB®
    % Two properties 'BoundingBox' and binary 'Image' corresponding to these
    % Bounding boxes are acquired.
    Iprops=regionprops(final,'BoundingBox','Image');  %error
    % Selecting all the bounding boxes in matrix of order numberofboxesX4;
    NR=cat(1,Iprops.BoundingBox);
    % Calling of controlling function.
    r=controlling(NR); % Function 'controlling' outputs the array of indices of boxes required for extraction of characters.
    if ~isempty(r) % If succesfully indices of desired boxes are achieved.
        I={Iprops.Image}; % Cell array of 'Image' (one of the properties of regionprops)
        noPlate=[]; % Initializing the variable of number plate string.
        for v=1:length(r)
            N=I{1,r(v)}; % Extracting the binary image corresponding to the indices in 'r'.
            letter=readLetter(N); % Reading the letter corresponding the binary image 'N'.
            while letter=='O' || letter=='0' % Since it wouldn't be easy to distinguish
                if v<=3                      % between '0' and 'O' during the extraction of character
                    letter='O';              % in binary image. Using the characteristic of plates in Karachi
                else                         % that starting three characters are alphabets, this code will
                    letter='0';              % easily decide whether it is '0' or 'O'. The condition for 'if'
                end                          % just need to be changed if the code is to be implemented with some other
                break;                       % cities plates. The condition should be changed accordingly.
            end
            noPlate=[noPlate letter]; % Appending every subsequent character in noPlate variable.
        end
        fid = fopen('noPlate.txt', 'wt'); % This portion of code writes the number plate
        fprintf(fid,'%s\n',noPlate);      % to the text file, if executed a notepad file with the
        fclose(fid);                      % name noPlate.txt will be open with the number plate written.
        winopen('noPlate.txt')

    %     Uncomment the portion of code below if Database is  to be organized. Since my
    %     project requires database so I have written this code. DB is the .mat
    %     file containing the array of structure of all entries of database.
    %     load DB
    %     for x=1:length(DB)
    %         recordplate=getfield(DB,{1,x},'PlateNumber');
    %         if strcmp(noPlate,recordplate)
    %             disp(DB(x));
    %             disp('*-*-*-*-*-*-*');
    %         end
    %     end

    else % If fail to extract the indexes in 'r' this line of error will be displayed.
        fprintf('Unable to extract the characters from the number plate.\n');
        fprintf('The characters on the number plate might not be clear or touching with each other or boundries.\n');
    end
    end

error: numberPlateExtraction Error using fprintf Invalid file identifier. Use fopen to generate a valid file identifier.

??? Error using ==> regionprops>ParseInputs at 837 Use bwlabel(BW) or double(BW) convert binary image to a label matrix before calling regionprops.

Error in ==> regionprops at 114 [L, requestedStats] = ParseInputs(officialStats, varargin{:});

Error in ==> numberPlateExtraction at 30 Iprops=regionprops(final,'BoundingBox','Image');

please help...Thanks! any better code for number plate recognition will be appreciated...

[Gayathri Saravanan]

The same above code I got error in r=controlling(NR) in free trail.can you help me sir

[Image Analyst]

@Gayathri Saravanan what version do you have? regionprops() no longer gives an error if the first argument is a binary image instead of a labeled image. But the error above refers to regionprops while youi say your error refers to some function you call controlling(). I suggest you read this link:

TUTORIAL: How to ask a question (on Answers) and get a fast answer

and then post your question as a new question in a new/ separate thread.

Answer 1

[Image Analyst]

Well the error message tells you exactly how to correct it

   Use bwlabel(BW)

and what did you do:

 % final=bwlabel(final);

You commented out the call to bwlabel(), for some reason. Put it back in like it told you to.

[nabeel javed]

Thanks sir!