Project1.py

# Project 1 : Webcam Color identification and draw using HSV color detection and
# contour detection, then use bounding boxes
import cv2
import numpy as np

frameWidth = 640
frameHeight = 480
cap = cv2.VideoCapture(0)  # inbuilt webcam
cap.set(3, frameWidth)
cap.set(4, frameHeight)
cap.set(10, 150)

myColors = [[33, 70, 0, 84, 254, 255],
            [0, 83, 175, 179, 255, 255],
            [65, 93, 187, 111, 196, 255]]
myColorValues = [[8, 26, 79],  # BGR
                 [46, 142, 255],
                 [204, 139, 70]]

myPoints = []  # [ x, y, colorID]


def findColor(img, myColors, myColorValues):
    imgHSV = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)
    count = 0
    newPoints = []
    for color in myColors:
        lower = np.array(color[0:3])
        upper = np.array(color[3:6])
        mask = cv2.inRange(imgHSV, lower, upper)
        x, y = getContours(mask)
        cv2.circle(imgResult, (x, y), 15, myColorValues[count], cv2.FILLED)
        if x != 0 and y != 0:
            newPoints.append([x, y, count])
        count += 1
        # cv2.imshow(str(color[0]),mask)
    return newPoints


def getContours(img):
    contours, hierarchy = cv2.findContours(img, cv2.RETR_EXTERNAL,
                                           cv2.CHAIN_APPROX_NONE)  # retrieves extreme outer contours
    x, y, w, h = 0, 0, 0, 0
    for cnt in contours:
        area = cv2.contourArea(cnt)
        if area > 500:
            cv2.drawContours(imgResult, cnt, -1, (255, 0, 0), 3)
            peri = cv2.arcLength(cnt, True)
            approx = cv2.approxPolyDP(cnt, 0.02 * peri, True)
            x, y, w, h = cv2.boundingRect(approx)
    return x + w // 2, y


def drawOnCanvas(myPoints, myColorValues):
    for point in myPoints:
        cv2.circle(imgResult, (point[0], point[1]), 10, myColorValues[point[2]], cv2.FILLED)


while True:
    success, img = cap.read()
    imgResult = img.copy()
    newPoints = findColor(img, myColors, myColorValues)
    if len(newPoints) != 0:
        for newP in newPoints:
            myPoints.append(newP)
    if len(myPoints) != 0:
        drawOnCanvas(myPoints, myColorValues)
    cv2.imshow("Video", imgResult)
    if cv2.waitKey(1) & 0xFF == ord('q'):
        break