A method for variable quantization in JPEG for improved text quality in compound documents
Konstantinos Konstantinides, Daniel R. Tretter · 2002
In this paper we present a JPEG-compliant method for the efficient variable quantization of compound documents. By measuring DCT activity in each of the 8/spl times/8 blocks, our scheme automatically detects the image parts and text parts of a document and adjusts the quantization scaling factors so that text blocks are compressed at higher quality than image blocks. Experimental results from three different quantization schemes are also reported.