Shadow detection on multispectral images

Dağlayan Sevim, Hazan
Shadows caused by clouds, mountains or high human-made structures pose challenges for identification of objects from satellite or aerial images since they deteriorate and mask true spectral properties of the objects. Therefore, they should be detected to accurately classify objects. Moreover, in change detection problems, shadows deteriorate performance because mere spectral changes act as actual object changes. Shadows are also useful as cues for estimating the height of an object or determining the time of recording. This study is dedicated to developing novel algorithms for detecting shadows on multispectral images using different color spaces. The proposed methods are compared with the methods in the literature.


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Ünlüsoy, Deniz; Süzen, Mehmet Lütfi; Department of Geological Engineering (2013)
In this study, four different image fusion techniques have been applied to high spectral and low spatial resolution satellite images with high spatial and low spectral resolution images to obtain fused images with increased spatial resolution, while preserving spectral information as much as possible. These techniques are intensity-hue-saturation (IHS) transform, principle component analysis (PCA), Brovey transform (BT), and Wavelet transform (WT) image fusion. Images used in the study belong to Çankırı reg...
Ghost Removal in High Dynamic Range Images
Khan, Erum Arif; Akyüz, Ahmet Oğuz; Reinhard, Erik (2006-10-11)
High dynamic range images may be created by capturing multiple images of a scene with varying exposures. Images created in this manner are prone to ghosting artifacts, which appear if there is movement in the scene at the time of capture. This paper describes a novel approach to removing ghosting artifacts from high dynamic range images, without the need for explicit object detection and motion estimation. Weights are computed iteratively and then applied to pixels to determine their contribution to the fin...
Hypothesis based detection of building with rectilinear projection in satellite images using shade and color information
Güdücü, Volkan; Halıcı, Uğur (2010-12-01)
A new hypothesis based method for detecting rectilinear buildings, that have ground projection made of combination of rectangles, in satellite images is proposed. While the hypotheses are established using the lines detected in the satellite images they are verified by using shadow and color segmentation information. The proposed method is implemented in MATLAB and tested in satellite images of different urban areas. The experimental results obtained are encouraging. ©2010 IEEE.
Image restoration for sparse aperture optical systems
Iskender, Berk; Öktem, Sevinç Figen (2018-07-05)
Sparse aperture imaging systems offer high spatial resolution while keeping the total light collection area smaller compared to their fully filled (monolithic) versions. Such systems are of interest in remote sensing and medicine applications where the size, weight, and cost of the imaging system are important. However, these systems often suffer from low image quality resulting from the non-filled sparse aperture structure. In this work, total-variation based image restoration is used to improve the image ...
Correlation-based variational change detection
Aktaş, Gizem; Yarman Vural, Fatoş Tunay; Department of Computer Engineering (2018)
Change detection is an important research topic for observing the earth but there are various challenges to obtain an accurate change map such as image noise, subtle differences and image acquisition alteration. Various studies handled these problems as separate steps. In the first step, images are registered, then the image noise are eliminated. After images are normalized to eliminate image acquisition differences, actual change detection routine can be applied as a final step. However, this step-by-step ap...
Citation Formats
H. Dağlayan Sevim, “Shadow detection on multispectral images,” M.S. - Master of Science, Middle East Technical University, 2015.