app.py

from flask import Flask,session,render_template,request,redirect,g,url_for,Response

import os
import time
import cv2 
app= Flask(__name__)
sub = cv2.createBackgroundSubtractorMOG2()  # create background subtractor
app.secret_key = os.urandom(24)

@app.route('/',methods=['GET','POST'])
def index():
    if request.method == 'POST':
        session.pop('user',None)

        if request.form['password'] =='password':
            session['user'] = request.form['username']
            return redirect(url_for('portected'))
    return render_template('index.html')

@app.route('/profile')
def portected():
    if g.user == 'fireman':
        return render_template('protected.html',user=session['user'])
    return redirect(url_for('index'))
    
def gen():
    """Video streaming generator function."""
    cap = cv2.VideoCapture(0)

    # Read until video is completed
    while(cap.isOpened()):
        ret, frame = cap.read()  # import image
        if not ret: #if vid finish repeat
            frame = cv2.VideoCapture(0)
            continue
        if ret:  # if there is a frame continue with code
            image = cv2.resize(frame, (0, 0), None, 1, 1)  # resize image
            gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)  # converts image to gray
            fgmask = sub.apply(gray)  # uses the background subtraction
            kernel = cv2.getStructuringElement(cv2.MORPH_ELLIPSE, (5, 5))  # kernel to apply to the morphology
            closing = cv2.morphologyEx(fgmask, cv2.MORPH_CLOSE, kernel)
            opening = cv2.morphologyEx(closing, cv2.MORPH_OPEN, kernel)
            dilation = cv2.dilate(opening, kernel)
            retvalbin, bins = cv2.threshold(dilation, 220, 255, cv2.THRESH_BINARY)  # removes the shadows
            contours, hierarchy = cv2.findContours(dilation, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
            minarea = 1000
            maxarea = 50000
            for i in range(len(contours)):  # cycles through all contours in current frame
                if hierarchy[0, i, 3] == -1:  # using hierarchy to only count parent contours (contours not within others)
                    area = cv2.contourArea(contours[i])  # area of contour
                    if minarea < area < maxarea:  # area threshold for contour
                        # calculating centroids of contours
                        cnt = contours[i]
                        M = cv2.moments(cnt)
                        cx = int(M['m10'] / M['m00'])
                        cy = int(M['m01'] / M['m00'])
                        # gets bounding points of contour to create rectangle
                        # x,y is top left corner and w,h is width and height
                        x, y, w, h = cv2.boundingRect(cnt)
                        # creates a rectangle around contour
                        cv2.rectangle(image, (x, y), (x + w, y + h), (255, 0, 0), 2)
                        # Prints centroid text in order to double check later on
                        cv2.putText(image, str(cx) + "," + str(cy), (cx + 10, cy + 10), cv2.FONT_HERSHEY_SIMPLEX,.3, (0, 0, 255), 1)
                        cv2.drawMarker(image, (cx, cy), (0, 255, 255), cv2.MARKER_CROSS, markerSize=8, thickness=3,line_type=cv2.LINE_8)
        #cv2.imshow("countours", image)
        frame = cv2.imencode('.jpg', image)[1].tobytes()
        yield (b'--frame\r\n'b'Content-Type: image/jpeg\r\n\r\n' + frame + b'\r\n')
        #time.sleep(0.1)
        key = cv2.waitKey(20)
        if key == 27:
           break
           
@app.route('/video_feed')
def video_feed():
    """Video streaming route. Put this in the src attribute of an img tag."""
    return Response(gen(),
                    mimetype='multipart/x-mixed-replace; boundary=frame')


@app.before_request
def before_request():
    g.user = None

    if 'user' in session:
        g.user = session['user']

@app.route('/dropsession')
def dropsession():
    session.pop('user',None)
    return render_template('index.html')

if __name__ == '__main__':
    app.run(debug=True, port=80, host='0.0.0.0')