Design And Development Of Cable HDTV STB Software Based On Davinci

The most popular method of HDTV source decoder is using the ASIC. ASIC has the advantage of strong processing, mature technology, and shorter product development cycles. But mostly ASIC has only specific function, lacks of flexibility and adaptability. Especially because of China's lower IC designing technology, we Chinese can only use foreign chips, making our products no intellectual property rights. Since DSP (Digital Signal Processor) comes out, it develops quickly . And in many areas DSP has been an substitute of ASIC. With the DSP processing power and speed's improvement, the use of generic DSP at the HDTV source decoder is quite possible.TI made Davinci technology, which made it possible of HDTV source decoders and STB running on a common DSP. TI introduced a Davinci processor TMS320DM6446. TMS320DM6446 integrated within a C64X+ (594MHZ) DSP core and an ARM926EJ-S (297MHZ) .Its peak computing capacity is 4752 MIPS, and it has a wealth of integrated on-chip peripherals, a dedicated video processing subsystem and a co-processor. Its operator Ability can fully meet the requirements of real-time HD decoder. So we choice TMS320DM6446 to run our Cable HDTV STB .This paper is about the software of the project "Design and Development of Cable HDTV STB Based on Davinci". The project uses TMS320DM6446 as the core processor, running the Linux operating system and realized the system control, TS demuxing, high-definition Degree (1080 I, 720P) and D1 (720×576) MPEG-2 video decoding, MPEG-2 audio decoding, AAC audio decoding, and so on. It has the OSD function, supporting multiple formats simulation (YPbPr, CVBS, VGA) and digital (DVI) video output. In addition, the system also has video capturing capabilities .It can achieve a variety of D1-level video encoding, including MPEG-2,H.264 encoding.And I also made a transplant and optimization of AVS decoder on DM6446.