Edge extracting method and apparatus using a neural network performing a function of diffusing an excitation. The method and apparatus continuously detect a variety of intensity changes of an image via a function having a variety of frequency characteristics. An edge of a fixed object is detected from images continuously input, and an edge of a moving object is selectively detected from the images. The edge extracting apparatus includes a first neural network which receives an image signal. The first neural network derives a Gaussian function representing the regularity of an excitatory response and an inhibitory response to a spot excitation of the image signal. The apparatus also includes a second neural network which detects edges of an image represented by the image signal by convolving the Gaussian function and the image signal.
Edge extracting method and apparatus using diffusion neural network