Patent Document ID: 8670982
Application ID: 11795085
Patent Flag: 1

Claim One:
1. A method of coding according to a second coding format, on the basis of information obtained by implementing at least one step of coding according to a first coding format, the first and second coding formats implementing, in particular for the coding of a speech signal, a step of searching for long-term prediction (LTP) parameters by exploring at least one dictionary having candidate parameters, one at least of the first and second coding formats using a multitap filtering with several coefficients for a fine search for the LTP parameters, the method comprising: a) conducting one of a statistical and analytical study, as a function of successive suites of LTP parameters according to the first coding format, so as to determine a number of orders and appropriate orders in a dictionary that the second coding format uses; b) recovering a priori information including information corresponding to a partition of the first dictionary relating to a class of the partition to which an LTP parameter obtained in the course of the coding according to the first coding format belongs, so as to select at least one order from said dictionary that the second coding format uses; c) applying the selected order to the candidate parameters of said dictionary that the second coding format uses so as to rank the candidate parameters; d) choose the m first ranked candidate parameters as a plurality of first candidate parameters, m depending on a desired quality or complexity; and e) performing the second coding by conducting the fine search for the LTP parameters only among said plurality of candidate parameters, wherein the first coding format uses a first dictionary and the second coding format uses a second dictionary, and wherein a plurality of similar orders is grouped so as to dynamically modify an initial partition of the first dictionary and, thereby, a number of orders of the second dictionary.