Compression of super high definition images using successive approximation wavelet lattice quantisation

A method of coding super high definition (SHD) still images based on lattice vector quantisation of wavelet coefficients is proposed. In this coding technique, each block of wavelet coefficients is coded by a series of vectors of decreasing magnitudes, resulting in a successive approximation process. It also exploits the structural similarities among the bands. This provides efficient coding together with the ability to guarantee arbitrary distortion levels for each band, which can be exploited to achieve optimum bit allocation. Conventional image compression techniques such as transform, sub-band and vector quantisation have already been tested for the coding of SHD images. Simulation results show that the proposed method achieves excellent coding performance and it outperforms other SHD image coding methods reported so far by more than 7 dB.<
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