CAP_PROP_FRAME_COUNT constant is missing in opencv `cv2` python module

Question

How to access to CAP_PROP_FRAME_COUNT from opencv in python? I tried this:

import cv2
cap = cv2.VideoCapture('myvideo.avi')
frames_count, fps, width, height = cap.get(cv2.CAP_PROP_FRAME_COUNT), cap.get(cv2.CAP_PROP_FPS), cap.get(cv2.CAP_PROP_FRAME_WIDTH), cap.get(cv2.CAP_PROP_FRAME_HEIGHT)

And this:

import cv2
import cv
cap = cv2.VideoCapture('myvideo.avi')
frames_count, fps, width, height = cap.get(cv.CAP_PROP_FRAME_COUNT), cap.get(cv.CAP_PROP_FPS), cap.get(cv.CAP_PROP_FRAME_WIDTH), cap.get(cv.CAP_PROP_FRAME_HEIGHT)

and also this:

import cv2
cap = cv2.VideoCapture('myvideo.avi')
frames_count, fps, width, height = cap.get(cv2.cv.CAP_PROP_FRAME_COUNT), cap.get(cv2.cv.CAP_PROP_FPS), cap.get(cv2.cv.CAP_PROP_FRAME_WIDTH), cap.get(cv2.cv.CAP_PROP_FRAME_HEIGHT)

But I'm getting this error:

AttributeError: 'module' object has no attribute 'CAP_PROP_FRAME_COUNT'

I'm using python 2.7.5 and OpenCV 2.4.9.

opencv3.0 will have the proper cv2.CAP_PROP_FRAME_COUNT (and also will discard the deprecated cv submodule) — berak, Oct 26 '14 at 08:59

score 20 · Accepted Answer · answered Oct 26 '14 at 00:22

20

The constants in the first version of OpenCV python module have a CV_ prefix. You could thus either use cv.CV_CAP_PROP_FRAME_COUNT or cv2.cv.CV_CAP_PROP_FRAME_COUNT.

answered Oct 26 '14 at 00:22

David Zwicker

23,581
6
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It seems to work, but... I'm quite bewildered. Why aren't those constants defined in the `cv2` module? – ProGM Oct 26 '14 at 05:26
11

In OpenCV 2.x, it appears that the constants are of the form `cv2.cv.CV_CAP_X`, while in OpenCV 3.x, they are `cv2.CAP_X` – cod3monk3y Nov 04 '15 at 15:02
3

Bad API, bad OpenCV. – acgtyrant Jul 08 '16 at 08:54

score 17 · Answer 2 · answered Jan 11 '16 at 07:32

While running macports on OSX (opencv @3.0.0_1+python27+tbb)

You can get CAP_PROP_FRAME_HEIGHT and CAP_PROP_FRAME_WIDTH with the following:

#!/opt/local/bin/python
import cv2 
vcap = cv2.VideoCapture()
# set frame width and height
vcap.set(cv2.CAP_PROP_FRAME_WIDTH, 480)
vcap.set(cv2.CAP_PROP_FRAME_HEIGHT, 640)
vcap.open(0)

score 5 · Answer 3 · answered Mar 22 '19 at 12:17

5

In OpenCV 2.x, these attributes are named starting with CV_... like CV_CAP_PROP_FRAME_COUNT.

In OpenCV 3.x and OpenCV 4.x, these attributes are named without CV_... like CAP_PROP_FRAME_COUNT.

answered Mar 22 '19 at 12:17

Qin Heyang

1,456
1
16
18

score 2 · Answer 4 · answered Dec 04 '15 at 02:38

http://docs.opencv.org/2.4/modules/highgui/doc/reading_and_writing_images_and_video.html#videocapture-get

#3. CV_CAP_PROP_FRAME_WIDTH
print "\t CAP_PROP_FRAME_WIDTH:     ",cap.get(3)
#4. CV_CAP_PROP_FRAME_HEIGHT
print "\t CAP_PROP_FRAME_HEIGHT:    ",cap.get(4)

http://docs.opencv.org/2.4/modules/highgui/doc/reading_and_writing_images_and_video.html#videocapture-set

#3. CV_CAP_PROP_FRAME_WIDTH
cap.set(3,320)
#4. CV_CAP_PROP_FRAME_HEIGHT
cap.set(4,240)

score -1 · Answer 5 · edited Nov 11 '14 at 19:53

-1

import cv2

import cv2.cv as cv

Using cv2:

stream = cv2.VideoCapture(filename)

print stream.get(cv.CV_CAP_PROP_FRAME_COUNT)

edited Nov 11 '14 at 19:53

lennon310

12,503
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answered Nov 11 '14 at 19:46

1kkwrds

9

CAP_PROP_FRAME_COUNT constant is missing in opencv `cv2` python module

5 Answers5

Using cv2: