A Design Approach Of Embedded Video Codec System Based On MPEG-4

Nowadays, the Embedded Video Surveillance technology is hotly discussed, which must be a new developing way to all video surveillance system. In this article, general situation about embedded video surveillance system is introduced briefly, and video server, which is the most important component in the whole system, is introduced in detail, including hardware design and low level software design. Relative to video server, the hardware design for video decoder system is also analyzed.In the hardware design for embedded video surveillance system, the design process is discussed step by step, including requirement analyzation, chip selection and circuit design. Meanwhile, components in this system are introduced in detail.In software design, low level implements such as hardware initialization are paid more attention. First, according to the main control chip in this system, AT91RM9200, the specific develop method and boot mode is introduced, and the porting for bootloader program is reported. Then the embedded Linux operation system suit for this video server is built, including kernel parameter passing, kernel porting, file system and disk file system. Finally, several device drivers for this server are deeply analyzed. These drivers are:Uart driver, Ethernet driver, audio out driver, video collecting and coding driver. Different driver has different method and structure, and the difference between them is mainly introduced.At last, the conclusion point out the characters and deficiencies of design for this video server. And urgent problems as well as new applications for embedded video server are proposed.