一种多制式视频格式转换接口电路的设计与实现

【作者】 张正全；

【导师】 徐国鼐；

【作者基本信息】 电子科技大学 ， 通信与信息系统， 2006， 硕士

【摘要】 当前,我国的家电产业都在积极努力开拓国际市场,然而由于历史原因,各国的标准清晰度模拟电视广播系统所采用的调制方式并不相同,加上家庭影院系统采用了多种视频接口输出视频信号,这些都要求我们的电视机有能力接收多种接口输入的多种格式的模拟视频信号。随着Internet技术的高速发展,高质量的视频信号可以通过网络传到千家万户,然由于技术和价格的原因,人们要求能用宽屏幕的电视机来欣赏计算机输出的视频节目。又随着数字电视的兴起,目前我国开始从模拟电视时代向数字电视时代转变,这个过渡期估计为5～10年左右,在此期间,模拟电视节目和数字电视节目同时播送,这样就存在模拟和数字电视节目接收兼容性的需求。大量的模拟电视机除了要接收原来的模拟电视节目外,还要能够收看新开播的数字电视节目,同时新的数字电视机也要能同时接收模拟和数字电视节目。所有这些都要求进行各种视频显示格式之间的转换,这就要求开发多格式视频转换接口,根据最终显示设备的显示要求对输入视频自动进行格式转换。首先,本文介绍了目前普遍被广泛应用的标准清晰度模拟方式视频信号、高清晰度视频信号和计算机输出视频信号,并对它们的扫描方式,调制方式,行/场参数等作了简要介绍。同时又对I2C协议和DVI1.0协议作了介绍。其次,本文设计和实现了一种多格式视频信号的格式转换接口电路,这个接口电路的主要功能是实现对输入的多种格式的视频信号进行视频格式转换。接口电路使用MA156芯片对标准清晰度模拟方式(PAL制、NTSC制和SECAM制)视频信号进行解码处理,被解码的信号再经模数转换后被编码为CCIR 656标准8位数据信号,最后用WSC1115芯片进行视频格式转换,并以模拟或数字方式输出。接口电路还用AD9883A芯片对高清晰度视频信号和VGA接口输出的模拟RGB视频信号进行模数转换,转换为24bits RGB数字视频信号,最后执行视频格式转换。又用SII1161芯片实现对DVI接口输出的T.M.D.S.数字差分视频信号的解码处理,恢复为24bits RGB数字视频信号,然后再进行视频格式转换。最后,对设计的视频格式转换接口电路进行了调试。更多还原

【Abstract】 Many TV manufacturers are actively exploiting overseas markets of televisions today. There are so many specifications of standard analogue TV broadcasting for many historical reasons that modern televisions have to be capacity of being input several types of video from different interfaces. With the high development of the Internet technology, high quality video are transmitted through the interconnect net. Up to now, the transformation from analogous TV period to digital TV period is determined by government, and according to the estimation this transformation would last for 5 to 10 years. During this interval, both analogous and digital TV broadcasting will have to be transmitted. Modern TV should be prepared for this situation and can receive both analog and digit videos. It’s obviously that the format conversion is required for the TV. In this paper we propose a new interface circuit to perform this task.First, videos with standard analogous format, high digital TV signals and videos from the computers are addressed. Many parameters of these formats, such as horizontal parameters, vertical parameters and scanning methods are given. Both I2C-bus protocol and DVI1.0 protocol are detailed, too.Secondly, the interface circuits which can perform the video format conversion is depicted. The circuits use the MA156 chip to decoder three types of standard analog format video, such as PAL, NTSC and SECAM, and digitalize them and encode the digital signals into the CCIR 656 standard format data. The signals of CCIR 656 are converted into the signals with the format that is suitable to the display devices. The analog-to-digital conversion is completed by AD9883A chip for the signals of HDTV from Y/Pr/Pb interface and analog RGB component signals from VGA interface. These digital signals from the AD988A also are converted into the desired format signals. The circuit for the format conversion of T.M.D.S. signals also is described.At last, the adjustment and testifying of the interface circuit is completed.更多还原