| 摘要 |
<p>A narrow-band audio signal (9) contains information, present as recognisable distortions, for processing the signal into a wide-band signal. In a method for processing a wide-band audio signal (1) into a narrow-band signal (9), a first spectral portion (4) is maintained unchanged in the narrow-band signal and information (7) usable for restoring remaining spectral portions (5) is embedded (8), preferably perceptually inaudible, by distorting said first spectral portion in a recognisable way, and preferably as a watermark. An encoder for coding a wide-band audio signal (1) into a narrow-band signal (9) and a decoder for decoding a narrow-band audio signal are disclosed, as well as a system for transmitting a wide-band audio signal through a narrow-band transmission channel, a system for storing a wide-band audio signal on a storage medium and retrieving the wide-band signal from storage, and a storage medium carrying a narrow-band audio signal.</p> |
