Get most recent frame from webcam

Question

I am using OpenCV2 to take some timelapse photos with a webcam. I want to extract the most recent view seen by the webcam. I try to accomplish this like so.

impo         


        

Answer 1

I have read that in the VideoCapture object there is a 5 frame buffer, and there is the .grab method that takes the frame but does not decode it.

So you can

cap = cv2.VideoCapture(0)
for i in xrange(4):
    cap.grab()
ret, frame = cap.read()
...

Answer 2

I found a bit of code from Capture single picture with opencv that helps. I modified it so that it continuously displays the most recent image captured. It doesn't seem to have a buffer problem, but I might have misunderstood your question.

import numpy as np
import cv2

cap = cv2.VideoCapture(0) # video capture source camera (Here webcam of laptop) 
ret,frame = cap.read() # return a single frame in variable `frame`


while(True):
    ret,frame = cap.read() # return a single frame in variable `frame
    cv2.imshow('img1',frame) #display the captured image
    if cv2.waitKey(1) & 0xFF == ord('y'): #save on pressing 'y' 
        cv2.imwrite('images/c1.png',frame)
        cv2.destroyAllWindows()
        break

cap.release()