DETECTION OF SHADOW IN URBAN COLOR AERIAL IMAGES
Jianjun Huang · Chinese Journal of Stereology and Image Analysis · 2003
The shadow regions in aerial image provide not only obvious evidences of objects higher than the surrounding background, but also obstructions for objects recognition. In this paper we first analyze the mechanism of shadow formation and the limitation of the photometric color invariants using illumination model. Then, combining with the characteristics of urban color aerial images and analysis of real image data, we deduce that the shadow regions in urban color aerial images have the characteristic of higher hue value. In consequence, a simple method for shadow detection in urban color aerial images is proposed, and several experiments show that the proposed method is effective.