Based on the concept of multi-resolutions, full search (FS) equivalent fast search methods for vector quantization (VQ) using mean-type pyramid have been developed in previous work.1-4) In this paper, a modified memory-efficient sum pyramid is proposed, which is exact for computing the difference in integer form and features one more new resolution L01 in-between the top 2 levels L0 and L1 of a conventional pyramid. Benefiting from a recursive difference computation at the top 3 levels, the proposed method can reduce the total computational cost obviously. Furthermore, a memory-efficient way of storage for the top 3 levels is integrated to reduce extra memory requirement.
- Fast encoding
- Modified memory-efficient sum pyramid
- Vector quantization
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics