LCO: A robust and efficient local descriptor for image matching

In this paper, a discriminating, yet very simple and efficient local descriptor, called local contrast and ordering (LCO), is presented for image matching. LCO descriptor employs sign and ordering of intensity differences to represent different local region characteristics. Specifically, for each pixel in a given interest region, LCO descriptor only calculates the intensity difference between current pixel and interest point. By using an exact ordering technology, ordering ambiguity is eliminated, and all pixels can be accurately divided into 6 intervals for simulating the positive and negative differences of high, middle, and low frequency. Our experiments are performed on a standard image data set, and the experimental results indicate that LCO descriptor achieves superior matching performance and higher computational efficiency than many popular local feature descriptors.