TI个人录像机(PVR)/数字媒体中心

高性能流媒体技术含盖了各种数字媒体技术和基于媒体的新兴技术，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，并改变了数字媒体内容传输的方式。流媒体所面临的挑战包括在有线和无线网络中的视频、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。

个人录像机/数字媒体中心部分组成元器件为：

TMS320DM644x：数字媒体处理器

TMS320DM64x：数字媒体处理器

THS7353：3路可选视频放大器

Filters, 2：1输入MUX和外部增益控制

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数字媒体处理器有IP使能的个人录像机/数字媒体中心应用方框图



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



TMS320DM6446数字媒体片上系统(DMSoC)方框图

The TMS320DM64x digital media processors offer the industry’s highest performance and are programmable protecting your code investment.On-chip video ports offer an easy connection to video devices and are capable of handling both video and audio encode/ decode for IP-based video infrastructure applications.

Key Features

* Performance up to 5760 MIPS at 720 MHz

* 400/500/600 MHz options also available

* Multiple input/output glueless interfaces for common video and audio formats

* Performance real-time video encoding, decoding/transcoding between CODECs

* Three dual-channel video ports support simultaneous video input/output

* Advanced connectivity with 10/100 Ethernet MAC and 66 MHz PCI

* Ready-to-use application software such as MPEG4, MPEG2, MPEG1,WMV9, H.263, H.261, M-JPEG, JPEG2000, JPEG, H.264 and more

Applications

* IP-based video conferencing and IP-based videophones

* Network camera-based surveillance and IP video node

* Video-on-demand set-top boxes, personal video recorders and digital media centers

* Statistical multiplexers and broadcast encoders



TMS320DM642数字媒体处理器方框图

Fabricated using the BiCOM-III process, the THS7353 is a low-power, three-channel integrated video buffer. It incorporates a selectable 5th-order Butterworth anti-aliasing/DAC reconstruction filter to eliminate data converter images. Each channel is individually I2C configurable.Its rail-to-rail
output stage allows for both AC and DC coupling applications, and the externally controlled gain adjust pin allows for fine tuning of the gain such as line driving, compensating for cable losses or Sin-X/X compensation.

Key Features

* 3 video buffers for CVBS, S-Video, SD/ED/HD YPBPR and RGB

* I2C control of all functions

* Integrated low-pass filters

* Selectable input bias modes

* 2:1 input MUX allows multiple input sources

* External gain control range: 0 dB to 14 dB

* Single supply: 2.7 V to 5 V

* Low quiescent current: 16.2 mA

* Differential gain/phase: 0.15%/0.3°

Applications

* HDTV video buffering

* PVR/DVDR output buffering

* Projector video buffering

* USB/Portable video buffering