PROBLEM TO BE SOLVED: To provide a determination method which can properly determine harmless vegetation areas (lawn areas) and harmful vegetation areas in a vegetation region by reducing an influence of data acquisition conditions such as seasonal variation, sunlight and the like and extracting the vegetation region from a color image. SOLUTION: A determination method of a vegetation region in a color image includes: a step for extracting pixels composing a vegetation region by using magnitude correlations between RGB values of respective pixels in a color image; a step for calculating an R/G value by dividing an R component value by a G component value for each pixel in the extracted vegetation region; a step for creating histogram by using the R/G values; a step for classifying the vegetation region as a single vegetation region or a mixed vegetation region by using a static obtained from the created histogram; a step for, when the vegetation region is classified as the mixed vegetation region, determining an area composed of pixels having R/G values less than a threshold in the vegetation region as a harmful vegetation area. COPYRIGHT: (C)2013,JPO&INPIT
