| 摘要 |
<p>Device and method for reduction of signal transients, where the signal is divided into frequency bands, the device at least comprising a transient detector (1), a calculating means, means for delaying a signal (2) and an adaptive filter. In the device an input signal (4) is arranged to both the means for delaying a signal (2) and the transient detector (1) via parallel connection, which both are connected to the adaptive filter (3) the output (5) of which is transient reduced. Characterizing is that the detector (1) detects frequency bands with a threshold function, which indicate presence of transient, and it indicates presence of transient if derivative and/or input signal (4) level exceeds predetermined levels. The detector (1) activates, at the indication of a transient in a frequency band, a calculating means for calculation of a set of filter parameters, describing the gain of the frequency bands, for controlling the transient reduction. If the detector (1) detects presence of transient in only one frequency band, the filter parameters accomplishes a total gain to a level determined by the level of the input signal (4). When the detector (1) no longer detects presence of transient the device goes back to the previous set of filter parameters.</p> |
