Block-adaptive subband coding of images

An error-free image decomposition/reconstruction method for subband coding is introduced. This method is used for blockwise subband coding. A partitioning algorithm is presented. The image is partitioned into blocks of identical size and then adjacent blocks of similar variances are merged. For each block, an adaptation of the subband number and bit allocation is made. The bit allocation algorithm uniformly distributes the quantization error into subbands and blocks. Examples clearly show that the peak-to-peak signal-to-noise ratio of the reconstructed images is better using the block-adaptive partitioning method than for subband coding of the entire image.<
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