Comparison of methods for edge detection with sub-pixel accuracy in 1-D images

Edge detection is often used procedure in digital image processing. For some practical applications is desirable to detect edges with sub-pixel accuracy. In this paper we present comparison of four methods for edge detection with sub-pixel accuracy in 1-D images: method based on approximation of real image function with erf function, moment-based edge operator, technique using spatial moments of the image function and the method based on wavelet transform of image. The paper presents results of simulations as well as of experiments to compare methods in terms of accuracy, the standard deviation of the edge localization error is chosen as precision criterion.