Patent ID: 8515770
Filing Date: 2013-08-20
Classification: G10H,G10L

Abstract:
1. Method for encoding excitation patterns from which the masking levels for an audio signal encoding are determined following a corresponding excitation pattern decoding, wherein for said audio signal encoding said audio signal is processed successively using different window and spectral transform lengths and a section of the audio signal representing a given multiple of the longest transform length is denoted a frame, and wherein said excitation patterns are related to a spectral representation of successive sections of said audio signal, said method including the steps: a) forming, for a current frame of said audio signal, in each case for a corresponding group of successive excitation patterns an excitation pattern matrix P, wherein for each one of said different spectral transform lengths a corresponding excitation pattern is included in said matrix P, and taking the logarithm of each matrix P entry, and wherein, in case the resulting matrix size is not suited for the transform of the following step, the size of the matrix is increased by copying a necessary number of times the values of an excitation pattern located at the matrix border; b) applying a two-dimensional transform on the logarithmized matrix P values, resulting in matrix P c) applying a pre-determined sorting order to the coefficients in said matrix P d) carrying out an encoding operation according to a set partitioning embedded block (SPECK) algorithm for matrix P