Background Subtraction

import cv2

cap = cv2.VideoCapture("street.mp4")
bg  = cv2.createBackgroundSubtractorMOG2(
        history=500, varThreshold=16, detectShadows=True)

while True:
    ret, frame = cap.read()
    if not ret: break
    fg = bg.apply(frame)

    # Shadow gray (127) সরাও, শুধু সাদা (255) রাখো
    _, mask = cv2.threshold(fg, 200, 255, cv2.THRESH_BINARY)
    mask = cv2.morphologyEx(mask, cv2.MORPH_OPEN,
                            cv2.getStructuringElement(cv2.MORPH_ELLIPSE,(5,5)))

    cv2.imshow("FG", mask)
    if cv2.waitKey(30) == 27: break

import cv2
bg = cv2.createBackgroundSubtractorKNN(
        history=500, dist2Threshold=400.0, detectShadows=True)

import cv2

cap = cv2.VideoCapture("traffic.mp4")
bg  = cv2.createBackgroundSubtractorMOG2(detectShadows=True)
line_y = 400; count = 0; centroids = []

while True:
    ret, f = cap.read()
    if not ret: break
    m = bg.apply(f)
    _, m = cv2.threshold(m, 200, 255, cv2.THRESH_BINARY)
    m = cv2.morphologyEx(m, cv2.MORPH_CLOSE,
            cv2.getStructuringElement(cv2.MORPH_ELLIPSE,(7,7)))

    cnts,_ = cv2.findContours(m, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
    for c in cnts:
        if cv2.contourArea(c) < 1500: continue
        x,y,w,h = cv2.boundingRect(c)
        cy = y + h//2
        if line_y-5 < cy < line_y+5: count += 1
        cv2.rectangle(f,(x,y),(x+w,y+h),(0,255,0),2)
    cv2.line(f,(0,line_y),(f.shape[1],line_y),(0,0,255),2)
    cv2.putText(f, f"Count: {count}", (20,40),
                cv2.FONT_HERSHEY_SIMPLEX, 1, (0,255,255), 2)
    cv2.imshow("count", f)
    if cv2.waitKey(30)==27: break