Patent ID: 6501860
Filing Date: 2002-12-31
Classification: G06T,H03M,H04N

Abstract:
A digital signal coding method including a step of analysing the digital signal into a plurality of frequency sub-bands distributed in at least two different frequency bands, at least one first sub-band having a lower frequency and at least one second sub-band having a higher frequency, including, for each second sub-band, the steps of:dividing the second sub-band into blocks, selecting first blocks which are to be coded by setting coefficients of each first block to a predetermined value and second blocks which are to be coded by trellis coded quantization, according to a selection criterion, linking the second blocks selected at the previous step in order to form a series of blocks, and coding the series of blocks by trellis coded quantization of a series of coefficients extracted from the second blocks of the second sub-band, wherein, for each of the blocks, the selection step includes: the coding of the block by setting to the predetermined value and by a second coding mode, the comparison of the coding by setting to the predetermined value and the second coding mode according to the selection criterion, and the selection of the coding by setting to the predetermined value if the block coded by setting to the predetermined value satisfies the selection criterion.