Patent ID: 9489964
Filing Date: 2016-11-08
CPC Classification: G10L

Claim Text:
1. A method of processing attenuation of pre-echo in a digital audio signal engendered on the basis of a transform-based coding, wherein the method comprises the following acts performed by a processing device: receiving a decoded signal from a decoder device that has decoded the digital audio signal into the decoded signal; detection of an attack position in the decoded signal; determination of a pre-echo zone preceding the attack position detected in the decoded signal; calculation of attenuation factors per sub-block of the pre-echo zone, as a function at least of a frame of the decoded digital signal in which the attack has been detected and of a previous frame of the decoded digital signal; attenuation of pre-echo in the sub-blocks of the pre-echo zone by the corresponding attenuation factors; and application of filtering of spectral shaping of the pre-echo zone on the current frame until as far as the detected position of the attack to produce a processed signal in which the pre-echo attenuation has been performed, the filtering being a zero-phase finite impulse response filtering with transfer function: