Getting AttributeError: 'NoneType' object has no attribute 'shape' error while woring in Kivy

Question

I am exploring kivy to deploy my ml model. I have wrote the code to access the camera using kivy but I'm getting AttributeError: 'NoneType' object has no attribute 'shape' error. Can Anyone help me?

Here is the error:

class MainApp(MDApp):
    def build(self):
        layout = MDBoxLayout(orientation='vertical')
        self.image =Image()
        layout.add_widget(self.image)
        layout.add_widget(MDRaisedButton(
            text="click here",
            pos_hint={'center_x': .5, 'center_y': .5},
            size_hint=(None, None)
        ))
        self.capture = cv2.VideoCapture(0)
        Clock.schedule_interval(self.load_video,1.0/30.0)
        return layout

    def load_video(self,*args):
        ret,frame = self.capture.read()
        #frame load and frame initialize
        self.image_frame = frame
        buffer = cv2.flip(frame,0).tostring()
        texture = Texture.create(size=(frame.shape[1],frame.shape[0]), colorfmt='bgr')
        texture.blit_buffer(buffer, colorfmt='bgr', bufferfmt='ubyte')
        self.image.texture = texture

Answer 1

I don't see a resolution anywhere in your code but when I ran into the same error using the example from Kivy documentation, I was able to fix it by changing my resolution from 640 x 480 to self.resolution