I am running the following code:
import numpy as np
import cv2
import os
count = 0
cap = cv2.VideoCapture("/home/simon/PROJECT/real_data/00000020.mp4")
while not cap.isOpened():
cap = cv2.VideoCapture("./00000020.mp4")
cv2.waitKey(1000)
print "Wait for the header"
pos_frame = cap.get(cv2.cv.CV_CAP_PROP_POS_FRAMES)
while True:
flag, frame = cap.read()
if flag:
# The frame is ready and already captured
cv2.imshow('video', frame)
pos_frame = cap.get(cv2.cv.CV_CAP_PROP_POS_FRAMES)
print str(pos_frame)+" frames"
else:
# The next frame is not ready, so we try to read it again
cap.set(cv2.cv.CV_CAP_PROP_POS_FRAMES, pos_frame-1)
print "frame is not ready"
# It is better to wait for a while for the next frame to be ready
cv2.waitKey(1000)
if cv2.waitKey(10) & 0xFF == 27:
break
if cap.get(cv2.cv.CV_CAP_PROP_POS_FRAMES) == cap.get(cv2.cv.CV_CAP_PROP_FRAME_COUNT):
# If the number of captured frames is equal to the total number of frames,
# we stop
break
if ret == True:
frame = cv2.VideoCapture.grab()
frame = 'frame%d' % count
cv2.imwrite('frame%d.png', frame)
count += 1
else:
print 'stopped at' + count
break
And whenever I run it, it loops on the while not loop, printing "wait for header". There is never an error code or anything like that either.
I have tried to run it as a more simple piece of code, where it doesnt have all these checks, and again that doesn't throw any errors.
I am attempting to run this code to open a video, and then save the frames as png files throughout the video.
Does anyone spot any particular problems with the code? Or alternatively does anyone know a piece of code that would do what i want more efficiently, as I have trawled through google searches and stack overflow a lot recently and haven't found anything
Thanks in advance Panda
You need to include a couple of DLLs in your python directory in order to play videos. Please see this for details:
https://li8bot.wordpress.com/2014/07/09/opencvpython-part-1-working-with-videos/
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