In this study, there is examined filtering based pansharpening methods which means of using sever... more In this study, there is examined filtering based pansharpening methods which means of using several 2D FIR filters in Fourier domain which implies that the filters are applied after taking 2D Discrete Fourier Transform of both multispectral and panchromatic image and after the pansharpening process in Fourier domain, the resulting pansharpened image is obtained with an inverse 2D DFT. In addition, these methods are compared with commonly used fusion methods which are combined as modulation based and component substitution based methods. The algorithms are applied to SPOT 6 co-registered image couples that were acquired simultaneously. Couples are chosen for three different regions which are a city image (Gebze/Turkey), a forest image (Istanbul/Turkey) and an agriculture field image (Sanliurfa/Turkey) in order to analyse the methods in different regional characteristics. These methods are compared by the fusion quality assessments that have common acceptance in community. The results of these quality assessments shows the filtering based methods had the best scores among the traditional methods.
2013 6th International Conference on Recent Advances in Space Technologies (RAST), 2013
ABSTRACT The advances in satellite technologies, image analysis techniques and computational powe... more ABSTRACT The advances in satellite technologies, image analysis techniques and computational power make possible processing huge amounts of high resolution images in real time. Acquiring high resolution images has a drawback, as the pixel resolution increases the surveyed area decreases. Multispectral scene is an image stack including numerous spectral bands from the electromagnetic wave spectrum, leading to richer spectral resolution. On the other hand, higher spatial resolution is included in the Panchromatic image. In order to have an image with higher spectral and spatial resolution, the applied merging process is called fusion. In this paper, fourteen different image fusion techniques were implemented. Serial implementations of all these approaches have longer execution time disadvantage compared to parallel approaches. To decrease execution time, the methods were modified with parallel computing approaches. This paper presents a comparison regarding speed performance of all fourteen methods' serial and parallel implementations to increase pixel resolution and keep spatial resolution high by combining spectral and spatial information of high and low resolution images of the same co-registered region. Additionally, spectral quality assessments of methods are presented.
InSAR stands for Interferometric Synthetic Aperture Radar and it is a technique used in remote se... more InSAR stands for Interferometric Synthetic Aperture Radar and it is a technique used in remote sensing and satellite geodesy. InSAR uses SAR images for generating surface maps for various applications. In these applications baseline parameter is a criteria for choosing right orbital tracks. In practice baseline is the perpendicular distance between two satellite passes in repeat-pass situations. This parameter is represented in different ways such as perpendicular, parallel, horizontal and vertical baselines. This paper presents the calculation of these presentations for Radarsat-1 satellite in order to use in InSAR researches.
The advances in satellite technologies, image analysis techniques and computational power make po... more The advances in satellite technologies, image analysis techniques and computational power make possible processing huge amounts of high resolution images in real time. Acquiring high resolution images has a drawback, as the pixel resolution increases the surveyed area decreases. Multispectral scene is an image stack including numerous spectral bands from the electromagnetic wave spectrum, leading to richer spectral resolution. On the other hand, higher spatial resolution is included in the Panchromatic image. In order to have an image with higher spectral and spatial resolution, the applied merging process is called fusion. In this paper, fourteen different image fusion techniques were implemented. Serial implementations of all these approaches have longer execution time disadvantage compared to parallel approaches. To decrease execution time, the methods were modified with parallel computing approaches. This paper presents a comparison regarding speed performance of all fourteen methods' serial and parallel implementations to increase pixel resolution and keep spatial resolution high by combining spectral and spatial information of high and low resolution images of the same co-registered region. Additionally, spectral quality assessments of methods are presented.
In this study, there is examined filtering based pansharpening methods which means of using sever... more In this study, there is examined filtering based pansharpening methods which means of using several 2D FIR filters in Fourier domain which implies that the filters are applied after taking 2D Discrete Fourier Transform of both multispectral and panchromatic image and after the pansharpening process in Fourier domain, the resulting pansharpened image is obtained with an inverse 2D DFT. In addition, these methods are compared with commonly used fusion methods which are combined as modulation based and component substitution based methods. The algorithms are applied to SPOT 6 co-registered image couples that were acquired simultaneously. Couples are chosen for three different regions which are a city image (Gebze/Turkey), a forest image (Istanbul/Turkey) and an agriculture field image (Sanliurfa/Turkey) in order to analyse the methods in different regional characteristics. These methods are compared by the fusion quality assessments that have common acceptance in community. The results of these quality assessments shows the filtering based methods had the best scores among the traditional methods.
2013 6th International Conference on Recent Advances in Space Technologies (RAST), 2013
ABSTRACT The advances in satellite technologies, image analysis techniques and computational powe... more ABSTRACT The advances in satellite technologies, image analysis techniques and computational power make possible processing huge amounts of high resolution images in real time. Acquiring high resolution images has a drawback, as the pixel resolution increases the surveyed area decreases. Multispectral scene is an image stack including numerous spectral bands from the electromagnetic wave spectrum, leading to richer spectral resolution. On the other hand, higher spatial resolution is included in the Panchromatic image. In order to have an image with higher spectral and spatial resolution, the applied merging process is called fusion. In this paper, fourteen different image fusion techniques were implemented. Serial implementations of all these approaches have longer execution time disadvantage compared to parallel approaches. To decrease execution time, the methods were modified with parallel computing approaches. This paper presents a comparison regarding speed performance of all fourteen methods' serial and parallel implementations to increase pixel resolution and keep spatial resolution high by combining spectral and spatial information of high and low resolution images of the same co-registered region. Additionally, spectral quality assessments of methods are presented.
InSAR stands for Interferometric Synthetic Aperture Radar and it is a technique used in remote se... more InSAR stands for Interferometric Synthetic Aperture Radar and it is a technique used in remote sensing and satellite geodesy. InSAR uses SAR images for generating surface maps for various applications. In these applications baseline parameter is a criteria for choosing right orbital tracks. In practice baseline is the perpendicular distance between two satellite passes in repeat-pass situations. This parameter is represented in different ways such as perpendicular, parallel, horizontal and vertical baselines. This paper presents the calculation of these presentations for Radarsat-1 satellite in order to use in InSAR researches.
The advances in satellite technologies, image analysis techniques and computational power make po... more The advances in satellite technologies, image analysis techniques and computational power make possible processing huge amounts of high resolution images in real time. Acquiring high resolution images has a drawback, as the pixel resolution increases the surveyed area decreases. Multispectral scene is an image stack including numerous spectral bands from the electromagnetic wave spectrum, leading to richer spectral resolution. On the other hand, higher spatial resolution is included in the Panchromatic image. In order to have an image with higher spectral and spatial resolution, the applied merging process is called fusion. In this paper, fourteen different image fusion techniques were implemented. Serial implementations of all these approaches have longer execution time disadvantage compared to parallel approaches. To decrease execution time, the methods were modified with parallel computing approaches. This paper presents a comparison regarding speed performance of all fourteen methods' serial and parallel implementations to increase pixel resolution and keep spatial resolution high by combining spectral and spatial information of high and low resolution images of the same co-registered region. Additionally, spectral quality assessments of methods are presented.
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