基于V4L2视频采集缓存机制应用与实现  

Application and Implementation of Video Capture Caching Mechanism Based on V4L2

作　　者：张辉[1] 李新华[1] 刘波[1] 钱翔[1] 

机构地区：[1]安徽大学电子科学技术学院,安徽合肥230039

出　　处：《现代电子技术》2010年第20期54-56,共3页Modern Electronics Technique

摘　　要：V4L是Linux针对视频设备的应用程序接口,V4L2为其升级版本,它修复了第一版的很多设计缺陷。然而它提供的常规读写函数并不能满足大数据量的高速传输,所以将缓存技术引入到视频采集领域可以提高系统的吞吐量。提出了一种双帧内存映射视频采集机制,由于不需要做数据拷贝动作,减少了读/写时限,因而可以提高视频采集性能。实验结果表明,采用双帧内存映射机制在视频采集时速度快,效率高,达到了预期的实验效果。V4L is an API, which is applied to video devices. V4L2 is an upgraded edition of V4L . However, since the conventional read and write function offered by V4L2 can＇t satisfy the high-speed transmission of mass data, the caching technology is introduced into the field of video capture to improve the system throughput. A video capture system with doubleframe memory map is proposed. As the system doesn＇t need to carry out data copy, the time limit of read and write is reduced, and the performance of video capture is improved. The experimental results show that the double-frame memory map adopted in video capture system can achieve the expected effect for its high speed and efficiency.

关 键 词：V4L2 LINUX 视频采集 内存映射 

分 类 号：TN919-34[电子电信—通信与信息系统] TP316[电子电信—信息与通信工程]