A Review : Shadow Detection And Shadow Removal from Images

  ijett-book-cover  International Journal of Engineering Trends and Technology (IJETT)          
  
© 2013 by IJETT Journal
Volume-4 Issue-5                      
Year of Publication : 2013
Authors : Shibam Das , Ambika Aery

Citation 

Shibam Das , Ambika Aery. "A Review : Shadow Detection And Shadow Removal from Images". International Journal of Engineering Trends and Technology (IJETT). V4(5):1764-1767 May 2013. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group.

Abstract

Shadows appear in remote sensing images due to elevated objects. Shadows cause hindrance to correct feature extraction of image features like buildings ,towers etc. in urban areas it may also cause false color tone and shape distortion of objects, which d egrades the quality of images. Hence, it is important to segment shadow regions and restore their information for image interpretation. This paper presents an efficient and simple approach for shadow detection and removal based on HSV color model in comple x urban color remote sensing images for solving problems caused by shadows. In the proposed method shadows are detected using normalized difference index and subsequent thresholding based on Otsu’s method. Once the shadows are detected they are classified and a non shadow area around each shadow termed as buffer area is estimated using morphological operators. The mean and variance of these buffer areas are used to compensate the shadow regions.

References

1]. Li Xu, Feihu Qi, Renjie Jiang, Yunfeng Hao, Guorong Wu A survey on shadow detection and shadow removal in real images.
[2]. Wang Junli ,Wang Shugen, 2002. A method of image shadow detection based RGB colour space. Information Technology, 26(12), pp.7 - 9.
[3]. Yan Li,Tadash i Sasagawa and Peng Gong,2004. A System of the Shadow Detection and Shadow Removal for High Resolution City Aerial Photo. ISPRS, COMMISSION
[4]. Barnes N.and Liu Z.Q,1999. Knowledge - based shape from shading. Int. J. of Pattern Recognition and Artificial In telligence, 13(1), pp.1 - 23.
[5]. Ortega A.and Shah M, 1998. From shape from shading to object recognition. Int. J. of Pattern Recognition and Artificial Intelligence, 12(2), pp.191 - 208.
[6]. Yang Yijun, Zhao Rongchun and Jiang Wenbing, 2002. Detection of s hadow areas from aerial imagery. Signal Processing,18(3),pp.228 - 232.
[7]. Wang, Ning ; Lang, Congyan ; Xu, De ,2011, Image - Based Shadow Removal via Illumination Chromaticity Estimation in Multimedia Information Networking and Security (MINES),pp. 33 - 36
[8]. Grégoire Mercier, Senior Member, IEEE A Complete Processing Chain for Shadow Detection and Reconstruction in VHR Images .

Keywords
Shadow detecti on, Thresholding,Shadow Removal.NSVI ( n ormalized saturation - value difference index (NSVDI) ,HSV( Hue - Saturation - Value ).