A Study on the IIR filters for Edge Detection

摘要: A new edge detecton method is proposed, which is based on the IIR (infini te impulse response) digital fi 1 ter. It is designed by the following two steps, First, the design of the anal og fi l ter the first and second smoothed differenti ating analog filters are obtained with multiplying the smoothing fi l ter (low pass filter) by S and Sº respectively in the Laplace transformed S-domain. Second, the design of digital fi l ter: the digital fi l ters are obtained by converting these analog filters by a bi linear transformation method, The proposed method has properties that the number of operations per output is independent of spectrum of this filters, and that the thinning results can be easi ly obtained with comparing the results of first derivative with that of second,