how to detect car from a video

foregroundDetector = vision.ForegroundDetector('NumGaussians', 3, ...
        'NumTrainingFrames', 50);
    V=VideoReader('video2.mp4');
    videoReader = vision.VideoFileReader('video2.mp4');
    for i = 1:150
        frame = step(videoReader); % read the next video frame
        foreground = step(foregroundDetector, frame);
       end
       imwrite(frame,'F:\referenceimage.jpg','jpg');
       videoPlayer = vision.VideoPlayer('Name', 'Detected Cars');
       videoPlayer.Position(3:4) = [650,400];  % window size: [width, height]
       se = strel('square', 3); % morphological filter for noise removal
       referenceimage=imread('F:\referenceimage.jpg'); 
       X=zeros(2,121);
       Y=zeros(2,121);
       Z=zeros;
       while ~isDone(videoReader)
           frame = step(videoReader); % read the next video frame
           % Detect the foreground in the current video frame
           foreground = step(foregroundDetector, frame);
           % Use morphological opening to remove noise in the foreground
           filteredForeground = imopen(foreground, se);
           %-----------------------SPEED ---------------------------%
           frame2=((im2double(frame))-(im2double(referenceimage)));
           frame1=im2bw(frame2,0.1); 
           [Labelimage]=bwlabeln(frame1); 
           stats=regionprops(Labelimage,'basic');
           BB=stats.BoundingBox;
           i=2; %fblasst for
           X(i)=BB(1);
           Y(i)=BB(2);
           Dist=((X(i)-X(i-1))^2+(Y(i)-Y(i-1))^2)^(1/2);
           Z(i)=Dist;
           M=median(Z);
           %disp(M);
           %clc;
           %disp('speed=')
           Speed=((M)*(120/8))/(4);
           %disp(Speed);
           %SPEED = M ???????????
           i = i + 1;
           SE = strel('disk',6); 
           frame3=imclose(frame1,SE); 
           step(videoReader); 
           pause(0.05);
              %if(i==121) end; ??
        %-----------------------SPEED ---------------------------%
        % Detect the connected components with the specified minimum area, and
        % compute their bounding boxes
        blobAnalysis = vision.BlobAnalysis('BoundingBoxOutputPort', true, ...
        'AreaOutputPort', true, 'CentroidOutputPort', true, ...
        'MinimumBlobArea', 150);
        %bbox = step(blobAnalysis, filteredForeground);
        [areas, centroids, bbox] = step(blobAnalysis, filteredForeground);
        % Draw bounding boxes around the detected cars
        result = insertShape(frame, 'Rectangle', bbox, 'Color', 'green');
        % Display the number of cars found in the video frame
        %ICI
        %disp(centroids); //show...
        %disp(size(centroids));//show....
        numCars = size(bbox, 1); %cars ...
        numCars_str = ['car number:', num2str(size(bbox, 1))];
        speed_str = [num2str(Speed),'KM/h'];
        result = insertText(result,[10,10],numCars_str, 'BoxOpacity', 1, ...
            'FontSize', 14);
        for i=1:size(bbox, 1)
        result = insertText(result,[centroids(i,1),centroids(i,2)], speed_str, 'BoxOpacity', 1, ...
            'FontSize', 20);
           end;
           step(videoPlayer, result);  % display the results
       end;
       release(videoReader); % close the video file

[KSSV]

Have you read this https://in.mathworks.com/help/images/detecting-cars-in-a-video-of-traffic.html ?

[Sandhiya CSE]

how to get pixel values of car

[Abhishek Kumar]

Hi Sandhya you can use "regionprops" function to get pixel values and several other parameters, if you are able to detect the car, in addition to link shared by KSSV, you can use the following link:

Measure properties of image regions - MATLAB regionprops (mathworks.com)

[Amirullah Bin Abdul Razak]

Hi,

Appreciate if someone explain this part? Which 2 frame should i use?

frame2=((im2double(frame))-(im2double(referenceimage)));

Thank you,

Amir