tutorial.py

# Step 1. Capturing the image.
# Step 2. Convert rgb to hsv.
# Step 3. Gaussian blur to the hsv converted image.
# Step 4. Morphological transformations to the Gaussian blurred image.
# Step 5. Searching contours
# Step 6. Navigate the car.

import cv2
import imutils
from imutils.video import VideoStream
import numpy as np
from directkeys import A, D, Space, ReleaseKey, PressKey

cam = VideoStream(src=0).start()
currentKey=list()

while True:
    key = False

    img = cam.read()
    img = np.flip(img, axis=1)
    img = np.array(img)

    hsv = cv2.cvtColor(img,cv2.COLOR_BGR2HSV)
    blurred = cv2.GaussianBlur(hsv,(11,11),0)

    colourLower = np.array([53,55,209])
    colourUpper = np.array([180,255,255])

    mask = cv2.inRange(blurred,colourLower,colourUpper)
    mask = cv2.morphologyEx(mask, cv2.MORPH_OPEN,np.ones((5,5),np.uint8))
    mask = cv2.morphologyEx(mask, cv2.MORPH_CLOSE,np.ones((5,5),np.uint8))

    width = img.shape[1]
    height = img.shape[0]

    upContour = mask[0:height//2,0:width]
    downContour = mask[3*height//4:height,2*width//5:3*width//5]

    cnts_up = cv2.findContours(upContour,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_SIMPLE)
    cnts_up = imutils.grab_contours(cnts_up)

    cnts_down = cv2.findContours(downContour,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_SIMPLE)
    cnts_down = imutils.grab_contours(cnts_down)

    if len(cnts_up) > 0:
        c = max(cnts_up,key = cv2.contourArea)
        M = cv2.moments(c)
        cX = int(M["m10"]/M["m00"])

        if cX < (width//2 -35):
            PressKey(A)
            key=True
            currentKey.append(A)
        
        elif cX > (width//2 +35):
            PressKey(D)
            key=True
            currentKey.append(D)
    
    if len(cnts_down) > 0:
        PressKey(Space)
        key = True
        currentKey.append(Space)

    img = cv2.rectangle(img, (0,0),(width//2-35,height//2),(0,255,0),1)
    cv2.putText(img,'LEFT',(110,30),cv2.FONT_HERSHEY_DUPLEX, 1, (139,0,0))

    img = cv2.rectangle(img, (width//2+35,0),(width,height//2),(0,255,0),1)
    cv2.putText(img,'RIGHT',(440,30),cv2.FONT_HERSHEY_DUPLEX,  1, (139,0,0))

    img = cv2.rectangle(img, (2*(width//5),3*height//4),(3*width//5,height),(0,255,0),1)
    cv2.putText(img,'NITRO',(2*(width//5) + 20,height-10),cv2.FONT_HERSHEY_DUPLEX,  1, (139,0,0))

    cv2.imshow("Steering", img)

    if not key and len(currentKey)!=0:
        for current in currentKey:
            ReleaseKey(current)

    key = cv2.waitKey(1) & 0xFF
    if key == ord('q'):
        break

cv2.destroyAllWindows()