A JPEG variable quantization method for compound documents.

Konstantinides, K; Tretter, D · IEEE Trans Image Process · 2000

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Abstract

In this paper, we present a JPEC-compliant method for the efficient compression of compound documents using variable quantization. Based on the DCT activity of each 8 x 8 block, our scheme automatically adjusts the quantization scaling factors so that test blocks are compressed at higher quality than image blocks. Results from three different quantization mappings are also reported.