Liang K-H, Tjahjadi T & Yang Y-H
Pattern Recognition, vol 30, no 5, 1997, 719-728
A scheme employing one-dimensional Regularized Cubic B-Spline (RCBS) fitting has been used successfully on the task of step edge detection. The regularized fitting is transformed into a quadratic energy equation to simplify the computation. This scheme however has three major limitations: it is non-linear; it has a limited accuracy; and it is computationally expensive. This paper presents a modified scheme which overcomes these limitations. The modified scheme employs the 1-D RCBS fitting on the horizontal and the vertical orientations of a window of an image to generate two 1-D signals, which provide sufficient information about the local property of the sub-image for roof edge detection. Experimental results show that the scheme of roof edge detection is very sensitive to small signals.