To increase the bit rate at which and the distance over which data can be transmitted by optical fiber, the device compensates the polarization dispersion of the line by processing the received optical signal by means of a polarization controller, means for generating a differential group delay between two orthogonal polarization modes and a control unit for the polarization controller. In at least some examples herein, an image of a calibration color chart is processed. A corresponding apparatus also is disclosed. Embodiments of the present invention further disclose an apparatus for buffering streaming media.