I'm trying to detect board in the image but the background color is so close and the corners of the board is circular like so i cant detect it with rectangle detection. Here is the code I used for this case. Would appreciate any help. Thanks
code:
def angle(pt1,pt2,pt0):
dx1 = pt1[0][0] - pt0[0][0]
dy1 = pt1[0][1] - pt0[0][1]
dx2 = pt2[0][0] - pt0[0][0]
dy2 = pt2[0][1] - pt0[0][1]
return float((dx1*dx2 + dy1*dy2))/math.sqrt(float((dx1*dx1 + dy1*dy1))*(dx2*dx2 + dy2*dy2) + 1e-10)
while(cap.isOpened()): #Capture frame-by-frame ret, frame = cap.read() if ret==True: #grayscale gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY) #Canny canny = cv2.Canny(frame,15,60) #contours canny2, contours, hierarchy = cv2.findContours(canny,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_SIMPLE) cv2.imshow('Contours', canny2) for i in range(0,len(contours)): #approximate the contour with accuracy proportional to #the contour perimeter approx = cv2.approxPolyDP(contours[i], cv2.arcLength(contours[i], True)*0.02, True)
#Skip small or non-convex objects
if(abs(cv2.contourArea(contours[i]))<200 or not(cv2.isContourConvex(approx))):
continue
elif(len(approx)>=4 and len(approx)<=6):
#nb vertices of a polygonal curve
vtc = len(approx)
#get cos of all corners
cos = []
for j in range(2,vtc+1):
cos.append(angle(approx[j%vtc],approx[j-2],approx[j-1]))
#sort ascending cos
cos.sort()
#get lowest and highest
mincos = cos[0]
maxcos = cos[-1]
#Use the degrees obtained above and the number of vertices
#to determine the shape of the contour
x,y,w,h = cv2.boundingRect(contours[i])
if(vtc==4):
cv2.putText(frame,'RECT',(x,y),cv2.FONT_HERSHEY_SIMPLEX,scale,(255,255,255),2,cv2.LINE_AA)
cv2.rectangle(frame, (x, y), (x + w, y + h), (255, 0, 0), 2)
#Display the resulting frame
cv2.imshow('frame',frame)
cv2.imwrite('/home/kaan/Downloads/Board.jpg', frame)
cv2.imshow('canny',canny)
cv2.imwrite('/home/kaan/Downloads/Edge.jpg', canny)
if cv2.waitKey(1) == 1048689: #if q is pressed
break
When everything done, release the capture
cap.release() cv2.destroyAllWindows()
