hsv = cv2.cvtColor(image, cv2.cv.CV_BGR2HSV)
cv2.imshow('hsv', hsv[:,:,0])
(thresh, im_bw) = cv2.threshold(hsv[:,:,0], 128, 255, cv2.THRESH_BINARY | cv2.THRESH_OTSU)
cv2.imshow('OTSU', im_bw)

# Smooth image
smoothed = cv2.adaptiveThreshold(input_image.astype(np.uint8), 255, cv2.ADAPTIVE_THRESH_MEAN_C, cv2.THRESH_BINARY, 41, 3)

# Some morphology to clean up image
kernel = np.ones((5,5),np.uint8)
opening = cv2.morphologyEx(smoothed, cv2.MORPH_OPEN, kernel)
closing = cv2.morphologyEx(opening, cv2.MORPH_CLOSE, kernel)