Research Of The Transportation Of The Maritime Multimedia Data Based On The Beidou System

In the field of maritime transportation, it’s an important means to ensure the safety of ship sailing that carrying out remote monitoring for the ship and providing shore-based information service. With the development of the global shipping business, the traditional textual data cannot meet the needs of supervision and service of the ship, the maritime multimedia data plays an important role in the communication of ship to shore (ship to ship) based on its vivid and accurate characteristics. However, maritime multimedia data is complex and huge. How to realize ttansmission of maritime multimedia data safely, effectively and economically is a problem that needs to be settled immediately. Based on Chinese Beidou system, this paper takes advantage of short-message communication ability to design communication protocols and control algorithm suitable for multimedia data transportation, realize ship to shore communication about little multimedia data.This paper analyzes the existing problems during Beidou system transports the maritime multimedia data, and raises the ideas and methods to solve them. Firstly, dealing with the problem of data length limited per single communication, the paper uses compression technique to sub-package and delivery. By analyzing several common digital image compression coding technology, combined with multimedia data compression requirement based on Beidou short-message, compared JPEG with JPEG2000, put forward to adopting JPEG2000to realize digital images compression; Secondly, the paper designs reliable transportation technology to solve the problem of possible data loss. According to Beidou communication protocols, combining with stop and wait protocol, continuous ARQ protocol etc, referring to re-transportation and confirmation mechanism of TCP/IP, analyzing the thought of sub-package and group package data. Finally, develope communication program according to the above design ideas.In this paper, I use two Beidou communication terminals to do an experiment about a small amount of data transports multimedia data. As the result of the experiment shows, the communication protocol and control algorithm designed are correct and efficient, they can realize sending and receiving image data. Therefore, applying Beidou system in maritime multimedia data transmission is feasible; the technology makes full use of function of Beidou short-message communication, and makes up for the shortage of maritime multimedia data transmission means.