def METHOD_NAME(self, track):
    """ write on track each time
    """
    self.tracks.resize(self.tracks.shape[0] + track.shape[0], axis=0)
    self.tracks[-track.shape[0]:] = track.astype(np.float32)
    self.curr_pos += track.shape[0]
    self.offsets.resize(self.offsets.shape[0] + 1, axis=0)
    self.offsets[-1] = self.curr_pos