METHOD FOR COMPRESSING VECTOR MAP DATA FOR GEOGRAPHIC INFORMATION SYSTEM IN ORDER TO ACHIEVE EFFICIENT STORAGE AND TRANSMISSION

摘要

PURPOSE: A vector data compressing method for effectively storage and transmission are provided to store and transmit the precise vector map data by providing hierarchical and attribute-independent compression technique about a vector map data. CONSTITUTION: Record information is extracted from a layer having a characteristic of a polygon and polyline(314). A MCA(Minimum Coding Attribute) is set to the recording information(316). A coordinate value of a characteristic is extracted from the MCA and is divided in an integer unit and a decimal unit. The coordinate value is extracted from the MCA and is separated into an integer unit and a decimal unit. The integer unit is rearranged into a deviation data and a code data by performing two step SEC(Spatial Energy Concentration)(340). The decimal unit uses shift operation and compression precision and is rearranged(342). The integer unit and the decimal unit data is compressed by an entropy coder(350).