A JPEG variable quantization method for compound documents
Konstantinos Konstantinides, Daniel R. Tretter · IEEE Transactions on Image Processing · 2000
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.