car detection in video as well as from the front camera

hey so this is the project i didnt get he satisfied output any one please try and help me out. i can guide you with the explaination

for the xml file

.................................................................................................................................

https://raw.githubusercontent.com/andrewssobral/vehicle_detection_haarcascades/master/cars.xml

.................................................................................................................

video:https://www.youtube.com/watch?v=d4L1Pte7zVc

just to check

import cv2

#use videocapture for online detection of cars

#video = cv2.VideoCapture(0)

video = cv2.VideoCapture("tesla_car_detect.mp4")

classifier_file ='car_detector.xml'

car_tracker = cv2.CascadeClassifier(classifier_file)

#1st approch

# Read until video is completed

while (video.isOpened()):

    # Capture frame-by-frame

    ret, frame = video.read()

    if ret == True:

        

        # Display the resulting frame

        cars  = car_tracker.detectMultiScale(frame)

        cv2.imshow('car detector machine',frame)

        for (x,y,w,h) in cars:

            cv2.rectangle(frame, (x,y),(x+w,y+h), (0,0,255),2)

    # Break the loop

    else:

        break

#2nd approch most effective approch

'''

while True:

    (read_succes,frame) = video.read()

   

    if read_succes:

        grayscale_frame = cv2.cvtColor(frame,cv2.COLOR_BGR2GRAY)

    else:

        break

    cars  = car_tracker.detectMultiScale(grayscale_frame)

    print(cars)

    

    for (x,y,w,h) in cars:

        cv2.rectangle(frame, (x,y),(x+w,y+h), (0,0,255),2)

        cv2.imshow('frame',frame)

'''

if cv2.waitKey(25) & 0xFF == ord('q'):

    video.release()

# Closes all the frames

    cv2.destroyAllWindows()

    print ("code completed")