A new localized phase congruency based object detector for X-ray images

In this paper, we present a novel method for automatically computing phase congruency at appropriate scales and orientations. Compared with Kovesi's phase congruency method, there are two distinct improvements in our method. First, our local phase information can be evaluated in a rotation invariant manner. Therefore, no orientation sampling is required. Second, the phase congruency is computed in a localized way, so there is no need to take all scales into consideration. Thus the computation load is reduced greatly and in the meanwhile this method can gain sub-pixel accuracy. We apply our algorithm to the endotracheal tube detection on X-ray image. Comparative experimental results show the efficiency of our method.