The Parsing Of Digital Service Information And Implementation Of Graphical User Interface Based On Embedded System

Today Digital Television (DTV) is becoming one of the most important research fields in all the international high technology research fields because of the huge potential economic profit.Although EPG is not any more"novelty", there are still different concepts about applications and technical implementation of EPG, and it still be considered as one of the hot spots in the research and development of DTV, this paper mainly discusses the implementation of STB EPG software system.Actually STB is an embedded system and EPG is a part of this embedded application software system. The EPG system can mainly divided into three modules: one module is to parse the PSI and SI information tables from the transport stream (TS) which includes PAT, PMT, NIT, SDT and EIT, and the information which parsed out from the table should be stored properly; another module is to make the Chinese character display on the TV screen, it needs to create a Chinese character storeroom in the software system and the Chinese character is stored with the BDF format in this system, at last we can successfully make the Chinese character display on the TV screen promptly and correctly; the last module is to create a series of GUI which is friendly and conveniently for users, users can easily know the EPG information by controlling the remote controller, this implementation is mainly relied on calling the OSD API of ST software package. The three modules are not isolated and they can communicate with each other by the message queue mechanism or other ways.Our system development is based on the ST STi5518 solution platform and the operation system we use is STLite/OS20 which is provided by ST Company too. The OS20 controls all the communication and synchronization between the tasks. This paper first introduces the principle of STB, details the OS20 real time operation system and DVB EPG system, and at last introduces the implementation of EPG in detail.Above all, the research prompts the development of STB in the digital television research field.