A novel intraframe source coding algorithm suitable for the recording of digital high definition television signals is presented. A multi-layered, hierarchical description of the source signal is obtained by means of a quad-tree, half-band wavelet transform. This transform decomposes the input signal into a collection of spectrally non-overlapping subbands. Individual subbands are quantised and entropy coded by using a novel predictive arithmetic coding technique. The algorithm is tuned to achieve bit-rate reduction ratios in the range 8:1-4:1 which is most useful for recording applications. Results obtained from simulating the coding algorithm, show noticeable improvement over the current state-of-the-art international standard algorithm for still picture encoding both in terms of subjective quality and of measured mean-square error.
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