This paper intruduce the basic theory and development of electronic halfton.Based onvolumes of information
several typical halfton methods were choosed and finished by softwares and some of the algorithms were improved.Compared with each other
different kindsof electronic halfton methods were deeply discussed by their features and applied rangers.Finally
we have designed a hardware of halfton algorithms for the demand of scanner.The result is that we can apply real-time halfton process to the gray-scale images.