Document Compression System based on Segmentation and SPIHT Coding

H.S. Lee and J. Chang (Korea)

Keywords

: compression, segmentation, subband oriented SPIHT coding, Quincunx lattice downsampling, ratedistortion control capability

Abstract

The document compression system is based on subband oriented SPIHT coding, document segmentation and Quincunx downsampling. The system segments the input document into the background, the foreground, and the bitmap. The purpose of segmentation is to have rate distortion control capability. The background is downsampled using Quincunx lattice producing two back1 and back2 images. The system wavelet transforms the back1, back2 and foreground and produces the wavelet coefficients. The wavelet coefficients are encoded using subband-oriented SPIHT coding. In reconstruction, back1 and back2 are merged together by Quincunx lattice to form the background. Then the foreground and the background are joined together to reconstruct the input document. In conclusion, we compare the compression rates and PSNR values of the proposed SPIHT coding system under various quantization schemes. We also present the rate-distortion control capability of the system by individual compression of the foreground and the background.

Important Links:



Go Back