Lossy to lossless image compression using allpass filters
Xi Zhang, Keijiro Kawai, Toshinori Yoshikawa, K. Takei · 2005
In this paper, an effective implementation of the allpass-based orthonormal symmetric wavelets is proposed for image compression. Since the orthonormal symmetric wavelets are used, it can be expected to get better compression performance than biorthogonal wavelets. Firstly, the implementation of irreversible real-to-real wavelets is presented and its decomposition process is shown by using allpass filters. Then, the realization of the reversible integer-to-integer wavelets is given by utilizing the invertible implementation of allpass filters. Finally, the coding performance of the orthonormal symmetric wavelets is evaluated and compared with the D-9/7 and D-5/3 wavelets. It is shown from the experimental results that the allpass-based orthonormal symmetric wavelets can achieve better compression performance than the D-9/7 and D-5/3 wavelets.