Review of Shadow Recognition and Mitigation Approaches in Various Fields of Image Processing

Information from the high-resolution satellite images can be extracted much more efficiently of present shadows of the objects or clouds from those images can be detected and removed. These shadow regions cause loss of information and sometimes get mixed with the darker objects. There are so many techniques are there in the present context related to the shadow identification with elimination, some are based on based on the geometric calculations and some are based on the property based. It is hard to detect the shadows from the geometrical approaches rather than the property based, as different geometric configurations are different for different types of location of images. For instance, an RGB and aerial image will have different properties rather than the color correction, in Multispectral images, there were be the information related to their thermal properties. In this review paper various methods related to shadow detection and correction are elaborated. Approaches are different and varies according to the applications. Some approaches are related to the applications of urban mapping and some related to the object tracking and image pixel ratios.