通过改变数字媒体内容传输方式，高性能数字媒体技术能够将视频、音频和数据内容集成到许多不同的新型应用中。数字媒体所面临的挑战包括在无线和有线网络中的视频、音频和数据流的同步处理中，如何实现实时性能、更高的信道密度和软件编程的灵活性。典型的数字媒体处理功能包括编码和解码媒体流，自动代码转换(transcoding)（将一种格式转换成另一种格式）和自动视频转换(transrating)流（将大比特率按比例缩放成小比特率）以适用于不同的体系水平。其它的处理功能包括压缩、解压缩、加密、信息分包以及媒体流的传输。

机顶盒部分组成元器件为：
TMS320DM644x 数字媒体处理器
TMS320DM64x™数字媒体处理器
MSP430x20x1/MSP430x20x2/MSP430x20x3: 微控制器
TFP510/TFP513: PanelBus™ 数字发送器
TSB43DA42: 第三代集成的IEEE 1394a Link/PHY
TSB41AB2: IEEE 1394a-2000 两端口电缆收发器/仲裁器
PCF8574/PCF8574A: I/O 扩展器
TS5A23157: 双路SPDT 5-V 模拟开关
PCA9539: 16位I2C和带中断的SMBus I/O 扩展器
PCA9545A: 4路带中断和复位的I2C 开关
PCM1850/PCM1851: 带输入复接器的立体声ADC
THS7303: 3路具有SAG修正的视频放大器

下面对各个元器件的性能和方框图进行描述：


下图为基于TMS320DM644x有VOD使能的IP机顶盒方框图



下图为基于TMS320DM64x™数字媒体处理器的VOD使能的IP机顶盒方框图



The TMS320DM6446/3 leverage TI’s DaVinci™ technology to meet the networked media encode and decode application processing needs of next-generation embedded devices. The DSP subsystem supports a programmable audio/video multimedia engine that provides application
flexibility and support for future CODEC standards. The integrated ARM®-based application processor supports all the required call control,device drivers and network provisioning. The Video Processing subsystem supports functions such as video resizing, On Screen Display (OSD) support, and a full compliment of video I/O capabilities.
Key Features
TMS320C64x+™ DSP performance: 600 MHz
ARM926EJ-S performance: 300 MHz
Video processing subsystem (VPSS) with configurable video/imaging peripheral
Highly integrated peripherals; including video accelerators, (4) DACs,hardware OSD, USB 2.0 and more
Advanced connectivity with 10/100 Ethernet MAC; half or duplex plus QoS support
Ready-to-use application software such as H.264, H.263, MPEG4,G.729ab, WVM9 and more
Supports glueless interfaces for common video and audio formats
Performance real-time image processing, resizing, auto focus and more
DDR2 and SDRAM support
Packaging: 361-pin Pb-Free BGA (ZWT suffix; 0.8-mm pitch)
Applications
Set-top boxes
Networked digital media centers
Home security



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