def compute_dr_wrt(self, wrt):
if wrt is self.px:
linop = lambda x : cv2.pyrDown(x.reshape(self.im_shape)).ravel()
return sp.linalg.LinearOperator((self.r.size, self.px.size), linop)
def compute_r(self):
result = cv2.pyrDown(self.px.r)
return result
