python cv2.goodFeaturesToTrack コーナー検出

import cv2

CORNER_COUNT=15
BLOCK_SIZE=3
QUALITY_LEVEL=0.1
MIN_DISTANCE=.0

img=cv2.imread('c:/temp/ts0.jpg')


gray=cv2.cvtColor(img,cv2.COLOR_RGB2GRAY)
corners =cv2.goodFeaturesToTrack(gray, CORNER_COUNT,QUALITY_LEVEL,MIN_DISTANCE,BLOCK_SIZE,useHarrisDetector=False)


for i in corners:
    x,y=i.ravel()
    x=int(x)
    y=int(y)
    cv2.circle(img,(x,y),4,(255,255,0),2)#ここ、x,yが整数でないと怒られます

cv2.imwrite('c:/temp/corners.jpg',img)
cv2.imshow('img',img)

cv2.waitKey(0)
cv2.destroyAllWindows()