Support Multi-standard System Of Interactive Digital Television Terminal

The Digital television is the significant technological revolution in the television history. It is developing with very high speed. With the digital television's widespread applications, it becomes the urgent requirement that watching digital television and receiving the data broadcasting on the multi-hardware platform and multi-operating system.The system designed in this thesis is the interactive digital television terminal system, which can support multi-standards. It can be used to receive, process and display the digital television signals. It also can fulfill many functions like accepting the subscribers' operations and interacting with the user etc.In the research and design of this subject, I referred to the researching method, designing logic and the testing standards of relative research in the same subject. The whole system design is based on the process-oriented programming method. The principle of design is the module separation. The interactivity between modules is performed through simple interface, in order to guarantee the clear logic, good maintenance and Scalability. The system design takes the principle into account that it occupies few resources and is with overall high performance. Standard C language is used considering the support of compilers on different platforms.This thesis mainly studied and compared the main digital television standards and the digital television middleware standards to find the sameness of them, designed the method that system calls the encapsulation to support the multi-hardware platform and multi-operating system, studied and realized receiving the digital television data stream using DSM-CC (Digital Storage Media-Command and Control)protocol, generated the XML and CSS parser codes automatically through writing the LEX & YACC files and formed the DOM(Document Object Model) trees. Then it can display the digital television signal by calling the digital television browser subsystem and interact with subscribers.In the aspect of system testing, the whole system already passed the customer's commercial application testing. It can fulfill the system requirements of playing video and audio, data broadcasting and interactivity with subscribers, etc. It has good performance, flexibility and scalability, and can achieve the customer's requirements.