基于VX1937的VGA／TV转换器的设计与实现

为了将PC机输出的VGA视频信号转换成适合普通电视标准的电视信号，设计了一款基于VX1937数字视频处理器的VGA/TV转换器。该系统根据VGA信号的刷新频率对一帧VGA运行扫描视频信号进行A／D采样，并经过缓冲、箝位，缓存在外部SDRAM中，经奇偶场重组和场内的数据插值处理后，在输出端经过D／A转换器转换为模拟视频信号。与传统的转换器相比．该系统支持多种分辨率，具有内建OSD功能。该系统具有无需软件支持、运行可靠、操作简单等特点。在飞机座舱VGA／TV转换器的设计实验中获得了质量较好的PAL制式标准电视视频信号。实验证明．该系统最高可将1024×768（60Hz）的真彩色逐行图像转换成NTSC或者PAL制式的视频信号，具有较高的应用价值．

Design and realization of VGA/TV converter based on VX1937

In order to convert PC-output VGA video signals into the standard TV signal,this paper designed a VGA/TV converter based on VX1937 digital video processor.Based on VGA signal refresh rate,the system firstly did A/D sampling for a VGA progressive scan video signal,then through the buffer and clamp,these data is cached in an external SDRAM, after parity farm restructuring and the venue of the data interpolation processing, these data is converted to analog video signals through the D/A sampling in the output end.Compared with traditional converters,it supports multiple resolutions and has built-in OSD functions.It can operate reliably without software support and is easy to operate.It was applied in the aircraft cabins VGA/TV converter design experiment,and a standard television PAL format video signal was gained. Experiments proved that the system can convert up to 1024×768 （60 Hz） of the true color image into a progressive format NTSC or PAL video signals, so it has high application value.