【作者】 王琛；

【导师】 甘育裕；

【作者基本信息】 重庆大学 ， 通信与信息系统， 2007， 硕士

【摘要】 信息的巨大作用和广阔市场,促进了通信产品发展的日益完善;人们对视觉信息的需求,多年来一直是社会科技进步的推动力之一;在“三网合一”的融合过程中,视频通信将是极其重要的市场驱动力。世界通信发展趋势是个人化、宽带化、智能化、数字化和IP化,而宽带化则是未来通信发展的主流,在语音通信业务已接近市场饱和状态下,中国各大电信运营商已不再投入重金发展传统的语音通信业务,个人视频电话通信必将成为未来通信业务的亮点。面对纷繁复杂的技术体系,论文首先研究IP视频电话现行的技术标准和协议,分析各种信令技术、音视频编码技术异同及优缺点,通过全面比较,考虑到H.323协议是目前在分组网上支持语音、图像和数据业务最成熟的协议,而H.264将成为广播电视领域、通信领域及存储媒体领域的统一标准。为提高视频电话的市场推广价值,本方案确定采用H.323协议和H.264视频编解码标准作为IP视频电话的技术标准。为克服IP视频电话存在的规模小、功能单一、价格昂贵、兼容性差、使用环境受限等诸多不足,本文紧紧结合新型HFC网络和综合业务终端展开分析研究,对IP视频电话的需求进行详细论证,在分析IP视频电话不同的实现方案后,注重充分发挥硬件和软件设计的互补特性,优化重组芯片资源和现有研究成果,确定选用基于ARM9的S3C2410来设计本文的IP视频电话,本方案论证充分、选型合理、产品成本低、市场适应能力强。论文还对IP视频电话的体系方案进行分析,然后重点围绕音视频采集和处理,从器件选型、接口及外围电路分析入手,设计IP视频电话的整体硬件方案,利用积木式构建法,采用数字USB摄像头和LCD显示器作为IP视频电话的视频采集和显示器件,即便于设计实现,又降低了产品价格。论文后面部分对IP视频电话的软件模块需求及设计实现进行研究,首先进行需求分析,再根据需求分析设计整个视频电话的软件结构,最后针对如何实现作具体的分析。同时,由于视频处理是IP视频电话设计中的关键部分,论文还重点对视频的采集与播放进行了软件设计和实现。更多还原

【Abstract】 The great function and a wide market of information makes a great impact on the development of the communication products. For many years, the need of better video information has been an important motive force for the developments of social sciences. In the period of“putting three networks into one”, the video communication will be a very important driver for the market.The tendency of the communication development worldwide is to be more personalized, broadband、intelligent, digitalized and IP, of which broadband is the greatest important aim for the development of communication. As the audio communication work is full of the market, each telecom businessman in china is no longer putting large quantity of money in developing the classical audio communication work, and personal video communication is sure to be a shinning point of the future communication.As the technical system is so complicated, this article firstly makes a brief survey of the present technical standards and agreements of the IP video telephone. After a concrete analysis of all kinds of information technology, the audio-video coding technology and their characters, it gives a completely comparison for them. And we take the H.323 agreement and the H.264 video coding standard as the technical standard of the IP video telephone, because at present the H.323 agreement is the most mature agreement which is supporting audio, picture and digital work in packet based networking and it is also helpful for putting the video telephone into the market.In order to overcome the shortcomings of small scale, single function, high price, poor compatibility, and limited usages of the IP video telephones, this article emphasizes on the demands of the IP telephones. Compared with HFC network and the Integrated Services Terminal, the article makes a concrete analysis on the different plans of IP video telephones. We decide to choose the S3C2410 plan which is based on ARM9 to design the IP video telephone. We considered that this plan is wholly discussed, the chosen design is reasonable, the cost is low, and it meets the needs of the market.The article also makes an analysis on the system plan of the IP video telephone, and then emphasizes on the collecting and dealing the audio-video information. It begins with the choosing of components, the interfaces, and the peripheral circuits, and then designs the whole hardware plan of the IP video telephone. It uses the way of“toy bricks”, and takes the digital USB camera and LCD display as the collecting and displaying components of the IP video telephone, which is not only helpful for designing, but also decreases the price of the products.The last parts of the article introduce the software model demands and the design of the IP video telephone. Firstly, it makes an analysis on demands, and then designs the software system of the whole video telephone, finally, it makes a specific analysis on how to put them into reality.And as the video treatment is the key part of the IP video telephone design, the article also focuses on the software design of the collection and broadcasting of the video pictures.更多还原