Patent Document ID: 7809191
Application ID: 11656002
Patent Flag: 1

Claim One:
1. An image processing system for an aerial photograph, which supports map-making by use of a photographic image, the image processing system comprising: a shadow-angle-analyzing processing unit that obtains a shadow-produced angle between a direction in which a shadow is extended and an east-west direction line, based on information of the photographic image and a shadow produced from a feature shown in the photographic image; a shadow-extension-ratio-analyzing processing unit that obtains a shadow-extended ratio, which is a ratio between a length of the shadow produced from the feature and a height of the feature, based on information of the photographic image, the length of the feature, and the shadow produced from the feature shown in the photographic image; a polygon-generating portion that generates a polygon by extracting lines constituting an outline of the feature shown in the photographic image and line-connection-processing these lines; and a shadow-area-extracting portion that generates a polygon of a shadow area by extracting the shadow area based on at least information on the shadow-produced angle and the shadow-extended ratio from the polygon generated by the polygon-generating portion; wherein the shadow-angle-analyzing processing unit, the shadow-extension-ratio-analyzing processing unit, the polygon-generating portion and the shadow-area-extracting portion are each implemented as hardware or a hardware/software combination.