In order to develop a universal machine vision algorithm to identify disease and pests of naval orange, blue component of images of naval orange with disease and insect pests was processed with background removed to detect and extract the boundary of disease and insect pests symptoms with improved watershed algorithm. With this boundary the disease and insect pests areas of the original color image were marked. Red, green, and blue components in marked area were used to characterize the color features, and boundary fractal dimension of disease and insect pests area was taken as the shape featu...
