The Software Design Of Streaming Media Transmission And Storage Server For Network Video Surveillance System

With the gradual increase of the city’s security demands, network video surveillance technology has become an important means to ensure the stability and the development of society. As an important part of video surveillance system, video data transmission directly influences the performance and scale of the system. For real-time video on demand and data storage to a large number of monitoring terminals, the traditional method, which uses unicast, tends to form a system bottleneck on network performance. Therefore, to improve streaming data transmission method in data forwarding and storage process has important significance for promoting the development of network video surveillance system.According to the data transmission demands of network video surveillance system, this thesis researches and develops the software of media transmission and storage server. Based on Linux platform, with multi-threading and network programming technology, the software achieves effective bandwidth-sharing mechanism on data transmission and storage, which improves the network performance of the system. Meanwhile, the software uses a variety of design patterns and improves the server’s scalability. According to the requirements of network storage, this thesis researches and develops an asynchronous data storage solution based on iSCSI protocol, which guarantees real-time video transmission, and promotes system integration. Meanwhile, according to the need of content-based retrieval in video surveillance, and aiming at the drawback of that fragmentation in traditional file system seriously affect storage performance, a dedicated file system for intelligent video surveillance, which based on bare disk, is developed. The proposed approach retrieves feature content based on feature video segments, and ensures high efficiency and stability of the file system by optimizing the strategies of data recycle, data writing and defragmentation.Test results of the media transmission and storage server’s software shows that under the typical video surveillance system network topology conditions, network delay of video data transmission is controlled within 100ms. What’s more, index strategies of the file system impact only 2.4% to storage bandwidth, compared to the traditional file system, it increases storage efficiency respectively on typical storage bitrate of 1 Mb/s, while the storage space has a high utilization rate.