code to detection the cars this code not counting cars properly How do i make it count correct ?

clc;

clear all;

MV = imread('cars1.png'); %To read image

MV1 = imread('backgnd.png');

A = double(rgb2gray(MV));%convert to gray

B= double(rgb2gray(MV1));%convert 2nd image to gray

[m1,n1,p1] = size(A);

[m2,n2,p2] = size(B);

m = max(m1,m2) ;

n = max(n1,n2) ;

A = imresize(A,[m n]) ;

B = imresize(B, [m n]) ;

[height, width] = size(A); %image size?

h1 = figure(1);

%Foreground Detection

thresh=11;

fr_diff = abs(A-B);

for j = 1:width

for k = 1:height

if (fr_diff(k,j)>thresh)

fg(k,j) = A(k,j);

else

fg(k,j) = 0;

end

end

end

subplot(2,2,1) , imagesc(MV), title (['Orignal Frame']);

subplot(2,2,2) , imshow(mat2gray(A)), title ('converted Frame');

subplot(2,2,3) , imshow(mat2gray(B)), title ('BACKGND Frame ');

sd=imadjust(fg);% adjust the image intensity values to the color map

level=graythresh(sd);

m=imnoise(sd,'gaussian',0,0.025);% apply Gaussian noise

k=wiener2(m,[5,5]);%filtering using Weiner filter

bw=im2bw(k,level);

bw2=imfill(bw,'holes');

bw3 = bwareaopen(bw2,5000);

labeled = bwlabel(bw3,8);

cc=bwconncomp(bw3);

Densityoftraffic = cc.NumObjects/(size(bw3,1)*size(bw3,2));

blobMeasurements = regionprops(labeled,'all');

numberofcars = size(blobMeasurements, 1);

subplot(2,2,4) , imagesc(labeled), title (['Foreground']);

hold off;

disp(numberofcars);% display number of cars

disp(Densityoftraffic);%display number of vehicles