How to get the duration of video using cv2

In OpenCV 3, the solution is:

import cv2cap = cv2.VideoCapture("./video.mp4")fps = cap.get(cv2.CAP_PROP_FPS)      # OpenCV2 version 2 used "CV_CAP_PROP_FPS"frame_count = int(cap.get(cv2.CAP_PROP_FRAME_COUNT))duration = frame_count/fpsprint('fps = ' + str(fps))print('number of frames = ' + str(frame_count))print('duration (S) = ' + str(duration))minutes = int(duration/60)seconds = duration%60print('duration (M:S) = ' + str(minutes) + ':' + str(seconds))cap.release()

cv2 is not designed to explore video metadata, so VideoCapture doesn't have API to retrieve it directly.

You can instead "measure" the length of the stream: seek to the end, then get the timestamp:

>>> v=cv2.VideoCapture('sample.avi')>>> v.set(cv2.CAP_PROP_POS_AVI_RATIO,1)True>>> v.get(cv2.CAP_PROP_POS_MSEC)213400.0

Checking shows that this sets the point after the last frame (not before it), so the timestamp is indeed the exact total length of the stream:

>>> v.get(cv2.CAP_PROP_POS_FRAMES)5335.0>>>> v.get(cv2.CAP_PROP_FRAME_COUNT)5335.0>>> v.set(cv2.CAP_PROP_POS_AVI_RATIO,0)>>> v.get(cv2.CAP_PROP_POS_FRAMES)0.0        # the 1st frame is frame 0, not 1, so "5335" means after the last frame

Capture the video and output the duration is seconds

vidcapture = cv2.VideoCapture('myvideo.mp4')fps = vidcapture.get(cv2.CAP_PROP_FPS)totalNoFrames = vidcapture.get(cv2.CAP_PROP_FRAME_COUNT);durationInSeconds = float(totalNoFrames) / float(fps)print("durationInSeconds: ",durationInSeconds,"s")