SunFounder picar-x - Page 69

SunFounder picar-x
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hsv = cv2.cvtColor(resize_img, cv2.COLOR_BGR2HSV) # Convert from BGR
˓→to HSV
color_type = color_name
mask = cv2.inRange(hsv,np.array([min(color_dict[color_type]), 60, 60]), np.
˓→array([max(color_dict[color_type]), 255, 255]) ) # inRange()Make the ones
˓→between lower/upper white, and the rest black
if color_type == 'red':
mask_2 = cv2.inRange(hsv, (color_dict['red_2'][0],0,0), (color_dict['red_2
˓→'][1],255,255))
mask = cv2.bitwise_or(mask, mask_2)
morphologyEx_img = cv2.morphologyEx(mask, cv2.MORPH_OPEN, kernel_5,iterations=1)
˓→ # Perform an open operation on the image
# Find the contour in morphologyEx_img, and the contours are arranged according
˓→to the area from small to large.
_tuple = cv2.findContours(morphologyEx_img,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_
˓→SIMPLE)
# compatible with opencv3.x and openc4.x
if len(_tuple) == 3:
_, contours, hierarchy = _tuple
else:
contours, hierarchy = _tuple
color_area_num = len(contours) # Count the number of contours
if color_area_num > 0:
for i in contours: # Traverse all contours
x,y,w,h = cv2.boundingRect(i) # Decompose the contour into the
˓→coordinates of the upper left corner and the width and height of the recognition
˓→object
# Draw a rectangle on the image (picture, upper left corner coordinate,
˓→lower right corner coordinate, color, line width)
if w >= 8 and h >= 8: # Because the picture is reduced to a quarter of
˓→the original size, if you want to draw a rectangle on the original picture to
˓→circle the target, you have to multiply x, y, w, h by 4.
x = x
*
4
y = y
*
4
w = w
*
4
h = h
*
4
cv2.rectangle(img,(x,y),(x+w,y+h),(0,255,0),2) # Draw a rectangular
˓→frame
cv2.putText(img,color_type,(x,y), cv2.FONT_HERSHEY_SIMPLEX, 1,(0,0,
˓→255),2)# Add character description
return img,mask,morphologyEx_img
with PiCamera() as camera:
print("start color detect")
camera.resolution = (640,480)
camera.framerate = 24
rawCapture = PiRGBArray(camera, size=camera.resolution)
time.sleep(2)
for frame in camera.capture_continuous(rawCapture, format="bgr",use_video_
˓→port=True):# use_video_port=True
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4.8. Color Detection 65