Study And Realization For Overlaying Meteorological Information And Electronic Navigation Chart

With the constant development of marine economy, the voyage is frequently increasing. The marine meteorological environment plays such an important part in ship navigation safety that it is important to provide timely meteorological information for marine navigators to grasp the future of the sea climate changes. Gridded Binary (GRIB) uses the GRIB code which belongs to the TDCFs (Table Driven Code Forms) suggested by the world meteorological organization. It is mainly used for the lattice point data of the numerical weather analysis and forecast, and can be directly filed for the standard pattern of the meteorological information.The essay bases on the Electronic chart display and information system which is designed by the National Research Center of Maritime Navigation System, encodes under the developer kits of VS2008 and realizes the superposition function of meteorological information and electronic chart and analyses meteorological information encoded by the GRIB to offer the convoy information including clear image and simple operation to marine navigators. On this way, the safety of the sea route gets effective guarantee.The essay firstly designs human-computer interface using WTL frame to realize the choice of actual time and the display of instant message. And then, designs data processing module and data painted module. The former is mainly responsible for handling the GRIB data obtained through Email, analyzes the GRIB data with eight groups as a basic unit, after that, provides external calls of the analyzed data. And the latter reads the wind data and air pressure data by calling the data processing module interface. For the wind data, plots to the chart according to the position of the data lattice point with the wind mark form. And for the air pressure data, calculates the data with same pressure, traces isophasm and generates isopiestic by calling COM component of the external isoline.Lables the isoline in the chart with certain interval to complete GRIB data visualization and visual processing and realize the superposition of the meteorological information and electronic chart.This paper in order to verify thethe results of design and implementation, intercepted four times meteorological data in one day of the first typhoon in 2011 near Taiwan sea area, and then compared the result after overlaying. Experimental results show that the thought of this design is correct and the method is feasible, and the results have a certain reference value.