ACELP / low frequency enhancement methods and devices in audio compression based on the TCX

摘要

A low-frequency emphasizing method involves the conversion coefficients that are grouped into blocks, the spectrum of a sound signal transformed in the frequency domain, the maximum energy of one block is calculated, one aspect of the invention, the maximum location index of the block with energy is determined, the coefficient is calculated for each block having a position index smaller than the position index of the block with maximum energy, for each block, gain, is determined from the coefficients, the transform coefficients of the block is applied to a method.