A New Coding Scheme for CT Image Using Integer-to-integer Shape Adaptive Discrete Wavelet Transforms

This paper proposes an integer-to-integer shape adaptive discrete wavelet transform(ISA-DWT) coding scheme for CT(computed tomography) image. The scheme consists of (1) extraction of shape information of the foreground of CT image; (2) integer-to-integer shape adaptive discrete wavelet transform; (3) the modified SPIHT algorithm. In CT image, the foreground contains useful clinical information and the background contains noise. In our scheme, only the foreground is compressed losslessly to avoid the unnecessary bit stream consumption. Experimental results indicate that the proposed scheme results in obviously improved performance as compared to the conventional integer-to-integer discrete wavelet transform.