Now a day’s capturing a live images with high quality plays an crucial role in all the fields. It is more important as far as security in military, commercial, household fields as well as to monitor the continuous changes in earth surfaces are concern. Most of the time to achieve clear images we have to differentiate between original object and shadow as detecting objects under the influence of shadow is a challenging task. In urban area the shadow produces artificial color features and shape deformation of objects which decays the quality of image. Shadow mainly occurs due to elevate objects and If light source has been blocked by some obstacles. However, a lot of shadowed areas in remote sensing images of urban areas have affected the tasks, such as image classification, object detection and recognition. Many times the shadow of image provides direct evidence for existing of large objects. The shadow is used for target recognition, building positioning, height estimation and slope calculation. The presence of shadow in very high resolution images can represent a serious obstacle for their full exploitation. Although shadow provide important visual clues for object shape perception, illumination position, object occlusion. Thus for the correct image interpretation it is important to detect shadow regions and restore their information. So it is very essential to detect the shadow regions and remove it effectively to get useful information with good quality. Significant researchers have been working on to develop the best shadow detection and removal algorithm which produces high accuracy results. Some researchers had implemented several methods and algorithm for detection and removal of shadow with experimental results. So this paper focuses on study of various methods of shadow detection and removal from images.

Shadow detection method, Shadow removal method

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