""" Apply different filters here """

import cv2  # import OpenCV 3 module

camera = cv2.VideoCapture(0)  # get default camera
mode = 2  # default mode, apply Canny edge detection
while True:
    ok, frame = camera.read()  # read frame
    if ok:  # frame is read correctly
        if mode == 2:
            frame = cv2.Canny(frame, 100, 200)  # Canny edge detection
        cv2.imshow('My camera', frame)  # show frame
    key = cv2.waitKey(1) & 0xff  # read keystroke
    if key == 27: break  # <Escape> key pressed, exit from cycle
    if key == ord('1'): mode = 1  # show unchanged frame
    if key == ord('2'): mode = 2  # apply Canny edge detection

camera.release()  # release web camera
cv2.destroyAllWindows()

""" Apply different filters here """

import cv2  # import OpenCV 3 module

camera = cv2.VideoCapture(0)  # get default camera
mode = 2  # default mode, apply Canny edge detection
while True:
    ok, frame = camera.read()  # read frame
    if ok:  # frame is read correctly
        if mode == 2:
            frame = cv2.Canny(frame, 100, 200)  # Canny edge detection
        if mode == 3:
            frame = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)  # convert to grayscale
            frame = cv2.Canny(frame, 100, 200)  # Canny edge detection
        cv2.imshow('My camera', frame)  # show frame
    key = cv2.waitKey(1) & 0xff  # read keystroke
    if key == 27: break  # <Escape> key pressed, exit from cycle
    if key == ord('1'): mode = 1  # show unchanged frame
    if key == ord('2'): mode = 2  # apply Canny edge detection
    if key == ord('3'): mode = 3  # apply Canny to gray frame

camera.release()  # release web camera
cv2.destroyAllWindows()

Apply Canny edge detection to grayscale. No big difference with colored Canny edge detection.
Apply Canny edge detection to grayscale. No big difference with colored Canny edge detection.

  """ Apply different filters here """
  
  import cv2  # import OpenCV 3 module
  
  camera = cv2.VideoCapture(0)  # get default camera
  mode = 2  # default mode, apply Canny edge detection
  while True:
      ok, frame = camera.read()  # read frame
      if ok:  # frame is read correctly
          if mode == 2:
              frame = cv2.Canny(frame, 100, 200)  # Canny edge detection
+         if mode == 3:
+             frame = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)  # convert to grayscale
+             frame = cv2.Canny(frame, 100, 200)  # Canny edge detection
          cv2.imshow('My camera', frame)  # show frame
      key = cv2.waitKey(1) & 0xff  # read keystroke
      if key == 27: break  # <Escape> key pressed, exit from cycle
      if key == ord('1'): mode = 1  # show unchanged frame
      if key == ord('2'): mode = 2  # apply Canny edge detection
+     if key == ord('3'): mode = 3  # apply Canny to gray frame
  
  camera.release()  # release web camera
  cv2.destroyAllWindows()
  
Apply Canny edge detection to grayscale. No big difference with colored Canny edge detection.
## Code Before:
""" Apply different filters here """

import cv2  # import OpenCV 3 module

camera = cv2.VideoCapture(0)  # get default camera
mode = 2  # default mode, apply Canny edge detection
while True:
    ok, frame = camera.read()  # read frame
    if ok:  # frame is read correctly
        if mode == 2:
            frame = cv2.Canny(frame, 100, 200)  # Canny edge detection
        cv2.imshow('My camera', frame)  # show frame
    key = cv2.waitKey(1) & 0xff  # read keystroke
    if key == 27: break  # <Escape> key pressed, exit from cycle
    if key == ord('1'): mode = 1  # show unchanged frame
    if key == ord('2'): mode = 2  # apply Canny edge detection

camera.release()  # release web camera
cv2.destroyAllWindows()

## Instruction:
Apply Canny edge detection to grayscale. No big difference with colored Canny edge detection.
## Code After:
""" Apply different filters here """

import cv2  # import OpenCV 3 module

camera = cv2.VideoCapture(0)  # get default camera
mode = 2  # default mode, apply Canny edge detection
while True:
    ok, frame = camera.read()  # read frame
    if ok:  # frame is read correctly
        if mode == 2:
            frame = cv2.Canny(frame, 100, 200)  # Canny edge detection
        if mode == 3:
            frame = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)  # convert to grayscale
            frame = cv2.Canny(frame, 100, 200)  # Canny edge detection
        cv2.imshow('My camera', frame)  # show frame
    key = cv2.waitKey(1) & 0xff  # read keystroke
    if key == 27: break  # <Escape> key pressed, exit from cycle
    if key == ord('1'): mode = 1  # show unchanged frame
    if key == ord('2'): mode = 2  # apply Canny edge detection
    if key == ord('3'): mode = 3  # apply Canny to gray frame

camera.release()  # release web camera
cv2.destroyAllWindows()
