会议电视系统的信号处理

Picture Signal Processing for Videoconference System

本文从数字视频信号的频谱及相关特性入手,分析并征明了正交亚取样及对角滤波是一种有效的预处理方法。它利用图象的二维频谱特性和会议电视信号的统计特性相匹配以咸少数字视频信号的数据率。本文还提出了一种用于时间分辨率及空间分辨率交换的运动自适应内插技术,它不仅改进了静止图象的分辨率,而且还增加了活动图象的连续感,研制了8.448Mb/s速率的会议电视系统CDVC-1的全部装置。该系统在福州和厦门之间开通使用,图象质量及稳定性都很好。

This paper, Considering the specialities of the spectra and correlations of digital videoconference signals, theoretically analyses and proves that the offset subsampling and diagonal filtering are the efficient pre-processing methods, which utilize the two-dimensional spectrum feature of picture to reduce the data rate of digital video sfgnals. It also matches the statistics specialities of videoconference pictures. At the same time, this paper also puts forward the scheme of motion adaptive interpolation for exchanging the spatial resolution and time resolution. Not only does this scheme improve the resolution in stationary pictures, but also reinforces continuinuity of moving pictures. Authors have accomplished the videoconference system (CDVC-1) complementation with these processing schemes at 8.448Mb/s datarate. This equipment is now working in the video- conferencing rooms of Fuzhou and Xiamen in Fujian province, China.