How to convert an opencv Mat into a numpy.ndarray?

Question

I have a code written in java (android) that open the camera of the phone and show frames. The below code represents the method in which we can retrieve frames. The project used

Answer 1

I found a solution by transforming the Mat into a byteArray in the java side

ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        bmp.compress(Bitmap.CompressFormat.PNG, 100, byteArrayOutputStream);
        byteArray = byteArrayOutputStream .toByteArray();

and in the python side the byteArray retrieved is transformed into a PIL image and then to a numpy array :

def call(imp):

    pic = Image.open(io.BytesIO(bytes(imp)))
    open_cv_image = np.array(pic)
    # Convert RGB to BGR
    frame = open_cv_image[:, :, ::-1].copy()
    im = imutils.resize(frame, width=min(300, frame.shape[1]))

Hope that could help.