An enhanced Wavelet-based scheme for near lossless satellite image compression

An enhanced wavelet-based compression scheme for satellite image is proposed in this paper. The Consultative Committee for Space Data System (CCSDS) presented a recommendation which utilizes the wavelet transform and the bit plane coder for satellite image compression. The bit plane coder used in the CCSDS recommendation encodes the coefficient block of bit planes one by one and then truncates the unnecessary bit plane coefficient blocks. By this way, the contexts of bit planes are not considered as the redundancy embedded data which may be compressed further. The proposed scheme uses a bit plane extractor to parse the differences of the original image data and its wavelet transformed coefficients. The output of bit plane extractor will be encoded by a run-length coder and will be sent to the communication channel with the CCSDS compressed data. Comparing with the recommendation of CCSDS, under a reasonable complexity, the subjective quality of the image will maintained or even better. In addition, the bit-rate can be further decreased from 85% to 95% of the CCSDS image compression recommendation at the similar objective quality level. By using the lower bit rate lossy mode compression and bit plane compensation, it is possible to obtain lower bit rate and higher quality image than which the higher bit rate lossy mode compression can achieve.