| 摘要 |
<p>Apparatus and method for compressing or expanding the level of an analogue input signal. The apparatus comprises an input for receiving an analogue input signal (2), signal processing means (6) for generating a digitised signal corresponding to the envelope of the input signal, and combining means (1) for combining the digitised envelope signal with the analogue input signal to provide the analogue output signal. When the apparatus is used to compress the level of an analogue input signal (2), the output signal (5) is proportional to the product of the input signal and the reciprocal of the envelope signal. When the apparatus is used to expand the level of an analogue input signal, the output signal is proportional to the product of the input signal and the envelope signal.</p> |
