Slight differences in output of MOG2 Background Subtraction in Python vs Swift (iOS)

3

Hi Crackwitz, thanks for the response. You were right it was too early to blame MOG2 specifically. What I have found is that loading a video in Python and Swift produces different images. Even different versions of opencv in Python has slightly different images. For example:

If I pick on opencv in Python in macOS using the version I built from source: 4.6.0-dev, when I load an image and then convert to grayscale and calculate the average pixel. I get Average: 122.1070775462963. If I run the same exact code on the same exact video clip using the version installed from pip I get: Average: 120.2203303433642

Code I am using:

    # Open video file 
    video = cv2.VideoCapture(test_case.video_fpath)
    # Check if camera opened successfully
    if (video.isOpened()== False):
        print("Error opening video stream or file")
        return output 

    ret, frame = video.read() 
    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
    print("Average: " + str(np.mean(gray)))