A perturbation-based pre-processing algorithm for CELP-coders

Abstract

A novel pre-processing algorithm for CELP-coders is proposed. The algorithm aims at perturbing the original signal slightly, such that the perturbed signal is subjectively indistinguishable from the original but can be coded more effectively. A key feature of the algorithm is the possibility of controlling the frequency domain properties of the perturbations. Preliminary simulations with the proposed algorithm in combination with a CELP-like coder indicate improvements in terms of segmental SNR and subjective speech quality.