A video is nothing but a sequence of frames and each frame is an image. By using OpenCV, all the frames that compose a video file can be extracted by executing imwrite() function till the end of video.

The cv2.read() function returns the next available frame. The function also gives a return value which continues to be true till the end of stream. Here, a counter is incremented inside the loop and used as a file name.

Following program demonstrates how to extract images from the video −

import cv2
import os

cam = cv2.VideoCapture("video.avi")

frameno = 0
while(True):
   ret,frame = cam.read()
   if ret:
      # if video is still left continue creating images
      name = str(frameno) + ''.jpg''
      print (''new frame captured...'' + name)

      cv2.imwrite(name, frame)
      frameno += 1
   else:
      break

cam.release()
cv2.destroyAllWindows()