Employing the interlaced scanning , current tv system can compress the frequency band of tv signal effectively and facilitate transmission . but this method reduces the scanning lines of pictures and the frequency of the field . it leads the pictures displayed on tv to have such disadvantages as large area flicker , edge flicker , interlace flicker , raster visibility and creeping line etc . to satisfy people " s vision feeling better , the big - screen , multi - function and high quality tv - set have been made great progress 现行的广播电视系统由于采用隔行扫描方式，从而有效地压缩了电视信号的频带，有利于传输；但由于这种方式使得图像的扫描行数少，场频低，导致了重显的电视图像有大面积闪烁、边缘闪烁、行间闪烁、行结构可见及行爬行等。
The author firstly finished the editing system interface to satisfy the editing function extension of the media asset management system and then selected the appropriate audio editing software , because the audio software is incompatible to the mp2 which is a common format audio in the broadcast and tv systems , so developed the module of the conversion of audio files 为满足媒体资产管理系统的编辑功能扩展需要,课题首先设计实现了编辑系统接口。然后选择合适的音视频编辑软件,针对音频软件不支持广播电视系统常用音频格式mp2的问题,研发出音频转换功能模块,最后将两者集成至编辑软件。
The essential intention of conditional access system ( cas ) is to achieve pay - tv of the digital broadcast system by means of subscriber management and authorization control . so cas is the key technology to realize the pay - tv and interact - tv . based on composite technology in transport layer , paper describes the production and structure of transport stream in mpeg - 2 standard , mpeg - 2 program special information and conditional access definition in service information from dvb standard 有条件接收系统( conditionalaccesssystem , cas ) ,其基本目的是通过对用户的授权控制和管理,实现数字广播电视系统的有偿服务,在为运营商带来经济上回报的同时,也能为用户提供更多、更高质量的服务内容,它是实现付费电视、交互电视的关键技术。
Fourthly , in the fields of industry structure and technology innovation , this thesis interprets the symptoms and historical cause of inner structure , regional structure and system structure of china ' s media . analyses the relationship between the technology level and the development of media industry , expounds the future market significance of six varieties of technologies . such original proposals and measures as public broadcasting system , broadcasting priority in country market are put forward 四是在媒体的产业结构创新和科技创新领域阐述了媒体产业的内部结构，区域结构和体制结构的问题症结及其历史根源，分析了我国媒体产业科技水平与媒体产业发展的关系以及六大急需取得突破的技术创新领域的未来市场意义，并在具体的创新程序和方法中，例如建立公共广播电视系统，农村市场广电优先、媒体动态垄断竞争型市场结构等诸方面提出了自己的见解。
With the continuous improvement of people s material living standards . the viewership of television programs and programs loops of a higher quality , the use of the growing popularity of digital microwave transmission . following is a system widely used in digital microwave radio and television transmission equipment 随着人民物质生活水平的不断提高，对电视节目的收视质量及节目套数提出了更高的要求，数字微波传输的使用日趋普及，以下是在广播电视系统广泛应用的数字微波传输设备
In the field of broadcasting and tv , since america announced the analog tv will be abolished till 2006 , the digital in the field of broadcasting and tv is impelled greatly , and all the developed country in the world enter into the train of developing the digital broadcasting and tv equipment and system 在广播电视领域，自美国宣布到2006年将全部废除目前的模拟制式电视广播和接收系统以来，广播电视领域的数字化浪潮以不可阻挡之势向前推进，世界各发达国家纷纷加入开发数字式广播电视系统和设备的行列。
