Pixel-ECC Based Laparoscopic Image Alignment In Presence of Large Untextured Regions

The performance of most of the image alignment algorithms degrades in the presence of untextured and homogeneous image regions. Such large regions, and thus inappropriate for using them for alignment, appeared in most of the biological objects. In this paper the Pixel-ECC image alignment algorithm to laparoscopic surgery tailored to avoid this form of degradation is proposed. This is achieved by the use of the Frobenius norms of the Hessian matrices of the image pair for the dynamic detection of the problematic regions in each iteration of alignment algorithm. The proposed algorithm as well as other state of the art image alignment algorithms are used in a number of experiments based on artificial and real laparoscopic data, and the proposed algorithm seems to outperform its rivals.