New methodology for adaptive vector quantisation

An image sequence coding scheme for low bit-rate video coding is presented. A new methodology is proposed for adaptive vector quantisation (AVQ), where the codebook is updated with new code-vectors. The new code-vectors replace less significant ones in the codebook, based on a novel scoring criterion that utilises a forgetting factor and codebook half-life. The proposed AVQ method gives rise to an additional performance enhancement of approximately 1 dB over frequency scoring techniques