video_contours.py

# Capture Video from Camera

import numpy as np
import cv2 as cv

cap = cv.VideoCapture('240fps.mp4')
# if not cap.isOpened():
#     print("Cannot open camera")
#     exit()
width = cap.get(cv.CAP_PROP_FRAME_WIDTH)
height = cap.get(cv.CAP_PROP_FRAME_HEIGHT)

fps = cap.get(cv.CAP_PROP_FPS)
print(f"width: {width}, height: {height}, fps: {fps}")
fourcc = cv.VideoWriter_fourcc(*'mp4v')
out = cv.VideoWriter('contours_240.mp4', fourcc, fps, (int(width), int(height)))

while cap.isOpened():
    # Capture frame-by-frame
    ret, frame = cap.read()
    # if frame is read correctly ret is True
    if not ret:
        print("Can't receive frame (stream end?). Exiting ...")
        break
    # Display the resulting frame
    gray = cv.cvtColor(frame, cv.COLOR_BGR2GRAY)
    ret, thresh = cv.threshold(gray, 100, 255, cv.THRESH_BINARY)

    contours, hierarchy = cv.findContours(thresh, cv.RETR_TREE, cv.CHAIN_APPROX_SIMPLE)
    with_contours = cv.drawContours(frame, contours, -1, (0, 255, 0), 1)

    # Show keypoints
    out.write(frame)
    cv.imshow("contours", with_contours)

    if cv.waitKey(1) == ord('q'):
        break

# When everything done, release the capture
cap.release()
out.release()
cv.destroyAllWindows()