In this paper, we propose an embedded satellite image compression method using Weighted ZeroBlock Coding (WZBC) and optimal sorting. In order to reduce average codeword length, Set Partition Embedded block (SPECK) and Embedded ZeroBlock Coder (EZBC) both encode significant block-sets with fixed-length bits, while WZBC assigns different-length bits to encode block-sets which contain different numbers of significant subblocks. In view of the context correlation among coefficients/blocks, WZBC employs a weight context to optimize the scanning order of the significance testing and the ratedistortion performance. Experimental results show that the proposed WZBC in binary coding mode provides excellent coding performance compared with those of SPECK and Set Partitioning In Hierarchical Trees (SPIHT) which use arithmetic coding, and can even closely approach that of JPEG2000. When arithmetic coding is extensively used, the proposed method has clear advantages.
In this paper, we propose an embedded satellite image compression method using the weighted zeroblock coding and
optimal sorting. Unlike the conventional quad-tree coding methods such as Set Partition Embedded block (SPECK) and
Embedded ZeroBlock Coder (EZBC), in the proposed weighted zeroblock coding (WZBC), 1) we use the unfixed
scanning order to code a significant block-set with fewer bits and achieve variable-length quad-tree coding; 2) we exploit
the significance degree of sub-blocks which is predicted by a novel context-based weighted strategy to optimize the
scanning order of the variable-length quad-tree coding and obtain the weighted zeroblock coding; 3) the rate-distortion
performance of WZBC is also optimized by using the above mentioned weight.
In the binary mode, the new method does not employ the arithmetic coding and has a fairly low complexity.
Experimental results show that the proposed WZBC in the binary coding mode can provide an excellent coding
performance compared with SPECK and Set Partitioning In Hierarchical Trees (SPIHT) with arithmetic coding, and can
even closely approach JPEG2000. When the arithmetic coding is extensively used, the proposed method can obtain more