Canny Edge Detection Algorithm Application for Analysis of the Potential Field Map
Earth Science India
Determination of potential fields' anomaly borders is a useful help to their interpretation. There is various technique of edge detecting that is applied in image processing. In this paper, the canny edge detection (CED) method has been proposed as boundary enhancement of the magnetic and gravity potential field data. The Canny operator works in a multi-stage process. This method is based on the characteristic of intensity values of considered pixel. The edge detector should have a good
... have a good signal-to-noise ratio, so that edges can be found even if potential field data quality is poor. For 2-dimensional bounds, residual potential field map is first smoothed by using a 2-D Gaussian filter. Afterwards, computing the horizontal gradients of the smoothed map and then using the gradient magnitude and direction to estimate borders strength and direction at every pixel. The Canny edge detection algorithm uses double threshold for edges revelation. In this research, a new procedure to define the thresholds has been suggested. The results obtained from the synthetic data set, with and without random noise, have been discussed. The method is demonstrated on real gravity and magnetic data set surveyed from Iran. The CED results are compared with three common methods as edge detector, namely the analytic signal, tilt angle and total horizontal derivative of the tilt angle.