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Sequential vector quantization of perceptually windowed DCT coefficients

In order to provide a high quality of the reconstructed images with a reduced transmission bit rate, taking into account both statistical redundancy and perceptual characteristics of the DCT coefficients, we apply perceptual windowing and sequential vector quantization to encoding of the coefficients: first, the coefficients are decomposed into 16 slightly overlapping subvectors so as that each subvector has reasonable dimension and conveys key information about one directional image, and then the decomposed subvectors are quantized in a sequential manner. The proposed scheme is good at encoding images with a wide range of transmission bit rates which can be easily controlled by adjusting only the stopping criterion of the sequential vector quantizer.