	US 7,574,354 B2
	Transcoding between the indices of multipulse dictionaries used in compressive coding of digital signals
Claude Lamblin, Perros Guirec (France); and Mohamed Ghenania, Le Mans (France)
Assigned to France Telecom, Paris (France)
Appl. No. 10/582,126 PCT Filed Nov. 24, 2004, PCT No. PCT/FR2004/003008 § 371(c)(1), (2), (4) Date Oct. 06, 2006, PCT Pub. No. WO2005/066936, PCT Pub. Date Jul. 21, 2005.
Claims priority of application No. 03 14489 (FR), filed on Dec. 10, 2003.
Prior Publication US 2007/0124138 A1, May 31, 2007
Int. Cl. G10L 19/12 (2006.01)

U.S. Cl. 704—223 [704/219]

23 Claims

1. A method for a transcoder for transcoding between a first compression codec and a second compression codec, said first and second codecs being of pulse type and using multipulse dictionaries in which each pulse has a position marked by an associated index, wherein the method comprises the steps performed by the transcoder:

a) the transcoder adapting coding parameters between said first and second codecs;

b) a decoder of the transcoder obtaining from the first codec a selected number of pulse positions and respective position indices associated therewith;

c) for each current pulse position of given index, a module of the transcoder forming a group of pulse positions including at least the current pulse position and the pulse positions with associated indices immediately below and immediately above the given index;

d) selecting as a function of pulse positions accepted by the second codec at least some of the pulse positions in an ensemble constituted by a union of said groups formed in step c); and

e) sending the selected pulse positions to the second codec for coding/decoding from the positions sent; said selection step d) then involving a number of pulse positions less than the total number of pulse positions in the dictionary of the second codec.