image.py 文件源码

def transform(self, translation, theta, method='opencv'):
        """Create a new image by translating and rotating the current image.

        Parameters
        ----------
        translation : :obj:`numpy.ndarray` of float
            The XY translation vector.
        theta : float
            Rotation angle in radians, with positive meaning counter-clockwise.
        method : :obj:`str`
            Method to use for image transformations (opencv or scipy)

        Returns
        -------
        :obj:`Image`
            An image of the same type that has been rotated and translated.
        """
        theta = np.rad2deg(theta)
        trans_map = np.float32(
            [[1, 0, translation[1]], [0, 1, translation[0]]])
        rot_map = cv2.getRotationMatrix2D(
            (self.center[1], self.center[0]), theta, 1)
        trans_map_aff = np.r_[trans_map, [[0, 0, 1]]]
        rot_map_aff = np.r_[rot_map, [[0, 0, 1]]]
        full_map = rot_map_aff.dot(trans_map_aff)
        full_map = full_map[:2, :]
        if method == 'opencv':
            im_data_tf = cv2.warpAffine(
                self.data, full_map, (self.width, self.height), flags=cv2.INTER_NEAREST)
        else:
            im_data_tf = sni.affine_transform(self.data,
                                              matrix=full_map[:, :2],
                                              offset=full_map[:, 2],
                                              order=0)
        return type(self)(
            im_data_tf.astype(
                self.data.dtype),
            frame=self._frame)