def get_gcps(self):
        """Read GCP from the GDAL band.

        Args:
           band (gdal band): Measurement band which comes with GCP's
           coordinates (tuple): A tuple with longitude and latitude arrays

        Returns:
           points (tuple): Pixel and Line indices 1d arrays
           gcp_coords (tuple): longitude and latitude 1d arrays

        """
        gcps = self.filehandle.gcps

        gcp_array = np.array([(p.row, p.col, p.x, p.y, p.z) for p in gcps[0]])

        ypoints = np.unique(gcp_array[:, 0])
        xpoints = np.unique(gcp_array[:, 1])

        gcp_lons = gcp_array[:, 2].reshape(ypoints.shape[0], xpoints.shape[0])
        gcp_lats = gcp_array[:, 3].reshape(ypoints.shape[0], xpoints.shape[0])
        gcp_alts = gcp_array[:, 4].reshape(ypoints.shape[0], xpoints.shape[0])

        return (xpoints, ypoints), (gcp_lons, gcp_lats, gcp_alts), gcps
Read GCP from the GDAL band.

        Args:
           band (gdal band): Measurement band which comes with GCP's
           coordinates (tuple): A tuple with longitude and latitude arrays

        Returns:
           points (tuple): Pixel and Line indices 1d arrays
           gcp_coords (tuple): longitude and latitude 1d arrays