Abstract
The purpose of this research is to develop automatic raw shiitake grading system using computer vision technique. This paper shows the image analysis method to judge the level of opening cap. There are raw shiitake mushrooms on blue background in the material images. The upper side of these raw shiitake mushrooms is lamella. Proposed method uses the lamella area of shiitake mushroom because the color of raw shiitake mushroom cap is almost same to lamella area. The gradient vectors in lamella tend to be perpendicular in the vectors from the center of shiitake area. The lamella area is extracted by this tangency. The rate of lamella area is used to judge the level of opening cap. If raw shiitake mushroom has stem, the rate of lamella area in half area that doesn't include stem area is used. AdaBoost algorithm is used to finally judge. Experiment shows that the rate of learning data is 92%.
