Data compression methods for document image including screened halftones

We have developed a new method for binarization and a coding scheme for the document image which is bi-level images including screened halftones such as dither coded images and error diffusion images and so on. The screened halftones area of the document image is not suitable for conventional compression techniques. We propose a new data compression method for screened halftones. Our proposed method makes use of segmentation of region, block coding operation and arithmetic coding operation. In this paper, we describe new data compression methods for document image including screened halftones.