An adaptive hierarchical image coding technique using transform vector quantization

We developed an adaptive hierarchical transform vector quantization (AHTVQ) coding technique which applies discrete cosine transform (DCT) coding of variable image block-size in combination with adaptive vector quantization (VQ) coding. To reduce complexity the subvectors are quantized with a cascaded VQ instead of full-search VQ (FSVQ). Simulation results presented show that compression rates and subjective quality compare favourably with methods previously described.<
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