Recently, computing environments move to pervasive computing age with rapid growth of internet and appearance of various mobile devices. This means computer offers more convenient life with linking between physical object and digital information. With these advance of computing environment, several researches are progress that are about tag interface to link between various physical objects and digital information, which are image code like as barcode, or wireless technology based like as RFID. It leads high expenses to read or write because RFID has to buy tags - as much as wanted - and has to need exclusive hardware. But image code can be printed to paper and can decode from camera connected to computer, so it is convenient and less maintenance cost. In this paper, we developed encoding and decoding algorithm for image code and applied algorithm to the tag interface to access the information more easy and fast in pervasive computing environment and develop.