Combining OpenCV, Python, Tkinter and PiCamera

Question

I'm having problems with using OpenCV, Python, Tkinter and PiCamera in a program.

• A Tkinter window is used to display and set the values to be used in OpenCV:

  

• I am trying to continuously read and process the video feed from PiCamera currently I am using:

   while True: for frame in camera.capture_continuous(rawCapture, format="bgr", use_video_port=True): root.update_idletasks() 

But after some reading on internet I found that using update() is not advisable, so I tried my luck to understand threading but I failed. There are a lot of examples with VideoCapture() which is used with USB cameras but not a lot with PiCamera. Is there any other way than threading?

Answer 1

You can use root.after(...) . Below is a sample code:

# define a variable used to stop the image capture
do_image_capture = True

def capture_image():
    if do_image_capture:
        camera.capture(rawCapture, format='bgr', use_video_port=True)
        # do whatever you want on the captured data
        ...
        root.after(100, capture_image) # adjust the first argument to suit your case

capture_image()

Below sample code is using thread:

import threading

stop_image_capture = False

def capture_image():
    for frame in camera.capture_continuous(rawCapture, format='bgr', use_video_port=True)
        # do whatever you want on the capture image
        ....
        if stop_image_capture:
            break

t = threading.Thread(target=capture_image)
t.setDaemon(True)
t.start()