Patent ID: 9536500
Date: 2017-01-03
CPC Classifications: G01C,G06T,G09B,G09G

Claim:
1. A map display device, comprising: a coordinate system definition section that defines a coordinate system on a map including element polygons showing constituent elements of an urban map; an inner and outer coordinate setting section that sets, as inner coordinates, coordinates located inside the element polygons and sets, as outer coordinates, coordinates located outside the element polygons; a moving average calculation section that calculates, for each coordinate in the coordinate system, a moving average value by using a predetermined window width, wherein the moving average of value for each coordinate in the coordinate system is calculated on the basis of one of the following expressions; wherein B(x,y) is assigned a first predetermined status value when (x,y) is located inside the element polygons, B(x,y) is assigned a second predetermined status value when (x,y) is located outside the element polygons, the value of α is a representative road width, and the value of predetermined window width is 2α+1; an inner coordinate resetting section that resets, as an inner coordinate, each of the outer coordinates which has the moving average value larger than a predetermined value; an urban polygon setting section that sets, as an urban polygon, a polygon along an outer periphery of a region formed of an aggregate of the inner coordinates that have been set by the inner and outer coordinate setting section and the inner coordinate that has been reset by the inner coordinate resetting section; and an urban map display section that enables the urban map to be displayed when a current location is present inside the urban polygon.