TEXTURE AREA EXTRACTION METHOD AND DEVICE THEREOF, FOREST AREA EXTRACTION METHOD AND DEVICE THEREOF, TEXTURE AREA EXTRACTION PROGRAM AND RECORDING MEDIUM WITH THE PROGRAM STORED, FOREST AREA EXTRACTION PROGRAM AND RECORDING MEDIUM STORING THE PROGRAM

摘要

PROBLEM TO BE SOLVED: To extract a forest area from an image of processing object, without using a method based on conventional multi-spectrum information.;SOLUTION: By noticing that edge tangential direction in the forest area has such a texture feature that the direction has no directivity but has randomness, based on a feature quantity qualitatively representing this tendency, the forest area is decided. More specifically, a block of arbitrary size with each pixel at its center is set, edge difference calculation is performed at each pixel, and based on the calculated edge difference value, the +parameter of an edge tangential line is acquired. Then, Hough transform is applied to the acquired edge tangential line parameter, each edge tangential line parameter is voted to a voting space with these edge tangential line parameters which have two axes of the space, an appropriate feature quantity is acquired from the acquired voting space; and based on this quantity, processing is conducted so that whether the representative points of the block or the whole of the block is the forest area is decided.;COPYRIGHT: (C)2004,JPO