how to read video in opencv python

1import numpy as np
2import cv2
3cap = cv2.VideoCapture('videos/wa.avi')
4while(cap.isOpened()):
5  ret, frame = cap.read()
6  gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
7  cv2.imshow('frame',gray)
8  if cv2.waitKey(1) & 0xFF == ord('q'):
9    break
10
11cap.release()
12cv2.destroyAllWindows()

1import cv2
2frameWidth = 640
3frameHeight = 480
4cap = cv2.VideoCapture("Resources/test_ video.mp4")
5while True:
6    success, img = cap.read()
7    img = cv2.resize(img, (frameWidth, frameHeight))
8    cv2.imshow("Result", img)
9    if cv2.waitKey(1) and 0xFF == ord('q'):
10         break
11

1import cv2
2filename_video = "path_to_your_video"
3
4input_video = cv2.VideoCapture(filename_video)
5if input_video.isOpened() == False:
6  print("Video not found")
7  sys.exit(1)
8else:
9  # Read until the video is completed
10  while(input_video.isOpened()):
11    # Capture frame by frame
12    ret, frame = input_video.read()
13    if ret == True:
14      frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
15      cv2.imshow('frame',frame)
16    else:
17      break
18	
19  input_video.release()
20  cv2.destroyAllWindows()