“…Many studies have developed grading machines based on normal image to detect the physical appearance of apples [1][2][3][4], or applied methods of laser image, hyperspectral image, near-infrared light, Raman spectrum, and weak light to detect the internal quality of the apples [5][6][7][8][9][10][11]. In this paper, a mass detection method based on particle area analysis is proposed, the appearance of apples can be detected to rapidly determine the surface characteristics, like color, texture, and surface defects, since apples from the same region, orchard, and of the same variety have similar internal quality, so as to allow the grading of apples after picking and before storage.…”