Signal processing using LUT filters based on hierarchical VQ

Vector quantization (VQ) is a powerful tool in signal processing. Hierarchical VQ (HVQ) is a method to implement VQ completely based on look-up tables (LUT). In HVQ, both encoders and decoders are inherently simple and fast, since there are no searches over codebooks. We introduce an overlapped HVQ (OHVQ) method, in which the number of samples is preserved after each HVQ stage. After the last stage, each OHVQ code in a particular location in the signal will map to a block (vector) which approximates that neighbourhood in the original sequence. For this reason, OHVQ is used as a basis to create a LUT-based filter, i.e. a spatial signal processor with very fast implementation. Preliminary analysis and image processing examples are shown demonstrating the efficiency of the proposed method.