单向传输设备中屏幕图像实时传输的研究

为满足涉密计算机用户对外网图文信息的实时接收、查看和监控等需求,设计并实现一种用于单向传输设备的屏幕图像实时传输系统.该系统采用镜像驱动方式快速、高效地获取屏幕图像;设计适合单向传输设备的屏幕图像实时传输协议用于在无反馈的情况下数据包能够实时传输到接收端;并通过发送相邻2张图像的异或数据减少系统所占带宽;以及每发送一定异或图像数据后发送一张完整图像的方法,解决传输过程中的丢包而导致接收图像错乱的问题.通过测试表明,该系统在低CPU使用率,低带宽占用率的情况下能够提供良好的实时图像传输服务,满足单向传输设备中屏幕图像实时传输的要求.

The Design and Implement of Real-time Screen Image Transmission System in Unidirectional Transmission System

To meet the classified computer users＇ demands on receiving, viewing, and monitoring real-time image or text information from the outer net, a screen image real-time transmission system used for unidirectional transmission device has been designed and realized in the paper. The system uses mirror driver to capture screen image fast and ef- ficiently. The protocol of image real-time transmission suitable for unidirectional transmission device is designed to guarantee the packet can reach the receiver real-time without feedback. XOR data of two adjacent images are sent to reduce the system bandwidth. A complete image is sent after sending a certain amount of images＇ XOR data, which can solve problems of receiving unordered image caused by packet loss during image transmission. The test shows that this system can provide well real-time image transmission services under the conditions of lower CPU utilization and bandwidth occupancy, and still meet the unidirectional transmission device on real-time screen image transmission requirements.