摘要
本文在H.323系统的组件网守的基础上，设计了基于Internet的流媒体传输控制系统(TCS)和相应的智能终端。TCS可以作为门户网站、电信增值运营商的基本软件系统，也可以理解为H.323语音教室网络的管理实体。它是所有H.323网络内呼叫的焦点。可以对语音教室，或者扩展为视频电话会议进行有效的管理和控制。它能提供基于H.323协议下很重要的功能，例如提供地址解析、访问控制、身份验证、带宽控制、安全检查、域的管理、呼叫控制信令以及呼叫管理等。为了有效地配合TCS的运行，自行开发了智能终端系统。该系统采用了基于硬件双核结构的TMS320VC5471为主的开发板。结合CPU两个内核不同的体系结构，在DSP内核上连接A/D、D/A模块实现语音信号I/O通道以及实时实现语音编解码算法，在ARM内核上移植了μCLinux嵌入式操作系统。终端嵌入的H.323应用系统、键盘、显示器等用户接口模块均由μCLinux统一管理和调度，可以很好的实现和运行TCS的服务器进行通信。最后，在现有科研水平和软硬件条件下，设计了数字化语音教室。整个设计综合应用了网络协议、嵌入式软件设计技术、多媒体技术、计算机微处理器技术等，为进一步研究和开发打下了坚实的基础。把嵌入式μCLinux移植到ARM内核的实践，为TI同类芯片(如DSC2X系列、DM系列、OMAP系列等双核CPU)进行操作系统移植提供了有价值的经验。
This paper designs stream media transmission control system (TCS) of internet and corresponding intelligent terminal based on H.323 system of constructing gatekeeper. TCS can be used as the basic software system for WWW and telecommunication value-added service dealer, furthermore it can also regard as management entity of H.323 speech classroom network. It can provide speech classroom and videophone with management and control. It has functions as follow: address resolution, access control, ID verifying, bandwidth control, safety examination, domain management, call control signalling and call management etc. In order to cooperate with TCS, intelligent terminal is developed. This system uses the EVM of dual-core TMS320VC5471. For the different core configuration, the DSP has A/D and D/A modules to implement speech signal I/O channel, real time implementation of speech coder. Meanwhile embedded operation system uClinux is transplanted into it. Terminal embedded H.323 application system, keyboard, display and
so on which all are managed and controlled by uCLinux to implement communication with TCS server. At last, digital speech classroom is designed under our technology and software & hardware conditions. The whole design applies the network protocol, embedded software designing technology, multimedia technology, microprocessors technology etc. that established the hard foundation for the further research and development. The application in
transplanting uClinux into ARM core is to provide the valuable experience to the TI's chips (ie. DSC2X, DM, OMAP etc. dual-core CPU).
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