Counting From Sky: A Large-Scale Data Set for Remote Sensing Object Counting and a Benchmark Method

Object counting, whose aim is to estimate the number of objects from a given image, is an important and challenging computation task. Significant efforts have been devoted to addressing this problem and achieved great progress, yet counting the number of ground objects from remote sensing images is barely studied. In this article, we are interested in counting dense objects from remote sensing images. Compared with object counting in a natural scene, this task is challenging in the following factors: large-scale variation, complex cluttered background, and orientation arbitrariness. More importantly, the scarcity of data severely limits the development of research in this field. To address these issues, we first construct a large-scale object counting data set with remote sensing images, which contains four important geographic objects: buildings, crowded ships in harbors, and large vehicles and small vehicles in parking lots. We then benchmark the data set by designing a novel neural network that can generate a density map of an input image. The proposed network consists of three parts, namely attention module, scale pyramid module, and deformable convolution module (DCM) to attack the aforementioned challenging factors. Extensive experiments are performed on the proposed data set and one crowd counting data set, which demonstrates the challenges of the proposed data set and the superiority and effectiveness of our method compared with state-of-the-art methods.