• Proceedings of the IEEK Conference
• /
• 2002.07b
• /
• pp.1244-1247
• /
• 2002

This paper discusses various algorithms to the fusion of multi-spectral image. These fusion techniques have a wide variety of applications that range from hospital pathology to battlefield management. Different algorithms in each fusion level, namely data, feature, and decision are compared. The PCT-Based algorithm, which has the characteristic of data compression, is described. The algorithm is experimented on a foliated aerial scene and the fusion result is presented.

• Proceedings of the Optical Society of Korea Conference
• /
• 2003.07a
• /
• pp.254-255
• /
• 2003

OCT (Optical Coherence Tomography)는 여러 단층영상 촬영기법의 하나로써 절개 없이도 생체의 복잡한 내부구조를 고분해능으로 이미징할 수 있는 장점을 갖고 있다. 고분해능 OCT 이미지는 사용되는 광원에 의해서 결정되는데 가우시안 형태를 갖는 넓은 파장대역의 광원일수록 높은 분해능이 가능하게 된다. OCT에서 사용되는 광원의 종류는 SLD, EELED, ASE등이 사용되고 있다. 그 중에서 ASE광원은 높은 출력 파워를 갖고 넓은 파장대역을 포함하지만 스펙트럼의 형태가 가우시안이 아닌 단점을 가지고 있다. (중략)

• Korean Journal of Remote Sensing
• /
• v.36 no.4
• /
• pp.545-555
• /
• 2020

This paper focuses on automatic image registration between EO (Electro-Optical) and IR (InfraRed) satellite images with different spectral properties using block-based approach and simple preprocessing technique to enhance the performance of feature matching. If unpreprocessed EO and IR images from Kompsat-3A satellite were applied to local feature matching algorithms(Scale Invariant Feature Transform, Speed-Up Robust Feature, etc.), image registration algorithm generally failed because of few detected feature points or mismatched pairs despite of many detected feature points. In this paper, we proposed a new image registration method which improved the performance of feature matching with block-based registration process on 9-divided image and pre-processing technique based on adaptive histogram equalization. The proposed method showed better performance than without our proposed technique on visual inspection and I-RMSE. This study can be used for automatic image registration between various images acquired from different sensors.

• Journal of Korean Society for Geospatial Information Science
• /
• v.10 no.5 s.23
• /
• pp.45-51
• /
• 2002

The goal of image merging techniques are to enhance the resolution of low-resolution images using the detail information of the high-resolution images. Among the several image merging methods, wavelet-based image merging techniques have the advantages of efficient decorrelation of image bands and time-scale analysis. However, they have no regard for spatial information between the bands. In other words, multiresolution data merging methods merge the same information-the detail information of panchromatic image-with other band images, without considering specific characteristics. Therefore, a merged image contains much unnecessary information. In this paper, we discussed this 'mixing' effect and, proposed a method to classify the detail information of the panchromatic image according to the spatial and spectral characteristics, and to minimize distortion of the merged image.

• Journal of Broadcast Engineering
• /
• v.16 no.1
• /
• pp.14-22
• /
• 2011

The conventional satellite image fusion methods usually add the same amount of higher frequency components extracted from the panchromatic image to all the multispectral images. However, it is noted that each of multispectral images has different amount of overlap with the panchromatic image in terms of its spectrum, and also has different intensities. Thus giving the same amount of high frequency contents to all the spectral bands does not match with this observation, which causes color distortion in the fused image. In this paper, we propose a new wavelet-domain satellite image fusion algorithm that can compensate for these differences in intensity and spectrum overlap. For the compensation of intensity differences, we first estimate the high resolution multispectral images from P, considering the relative intensity ratios. For the compensation of the amount of spectral overlap, their wavelet coefficients are appended to the conventional wavelet-domain method where the coefficients for the addition is determined by the amount of spectrum overlap. Experiments are conducted for the IKONOS satellite images whose spectrums are well known, and the results show that the proposed algorithm gives higher PSNR and correlation coefficients compared to the conventional methods.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2006.04a
• /
• pp.139-144
• /
• 2006

Forest fire is due to difficulty in approaching the forest fire at the time of forest fire and quite a long of time required for post-fire investigation, accurate analysis of damages to the forest area caused by forest fire is difficult to obtain. Recently, In attempt to overcome such difficulty, many researches are using satellite images. Nevertheless, it is not easy for everyone to obtain the satellite image data, and additional researches in order to verify accuracy of such data are also required. Therefore, in this study for satellite image to about damages to the forest areas caused by forest fire using tile selected two data of spectral reflectance of the vegetation, gained by using a spectrometer. That is we wished to search about mistake that is apt to happen by one time eyesight observation by analyzing two datas that is used spectral radiometer 3 months and 6 months later and gets.

• Proceedings of the KSRS Conference
• /
• 2003.11a
• /
• pp.902-904
• /
• 2003

The main objective of this paper is to investigate the potential utility of multisensor remotely sensed data for improved coastal wetland mapping. Five data fusion models, three algebraic models (Multiplicative (MT), Brovey (BT) and Wavelet transform (WT)) and two spectral domain models (Principals component transform (PCT) and Intensity-Hue-Saturation (IHS)) were implemented and tested over the multisensor data. The fused images were then compared based on visual and statistical approaches. The results show that the wavelet transform provides greater flexibility for combining optical data sets and has good potential for preserving the spatial and spectral content of the original images . However, this model yields poor information when combining optical and microwave data. Brovey transform is more reliable for fusing optical and microwave image data and yields improved information about different wetland features of the coastal zone.

• Korean Journal of Remote Sensing
• /
• v.27 no.6
• /
• pp.717-728
• /
• 2011

An efficient method for the unsupervised classification of high resolution imagery is suggested in this paper. It employs pixel-linking and merging based on the adjacency graph. The proposed algorithm uses the neighbor lines of 8 directions to include information in spatial proximity. Two approaches are suggested to employ neighbor lines in the linking. One is to compute the dissimilarity measure for the pixel-linking using information from the best lines with the smallest non. The other is to select the best directions for the dissimilarity measure by comparing the non-homogeneity of each line in the same direction of two adjacent pixels. The resultant partition of pixel-linking is segmented and classified by the merging based on the regional and spectral adjacency graphs. This study performed extensive experiments using simulation data and a real high resolution data of IKONOS. The experimental results show that the new approach proposed in this study is quite effective to provide segments of high quality for object-based analysis and proper land-cover map for high resolution imagery of urban area.

• Proceedings of the KSRS Conference
• /
• 2004.10a
• /
• pp.432-435
• /
• 2004

MSC (Multi Spectral Camera) system is a remote sensing payload to obtain high resolution ground image. In this application, uniformity characteristic is important as well as GSD (Ground Resolved Distance) and SNR (Signal to Noise Ratio). MSC image chain is consisted of OM (Optical Module), CCD, Video processor, NUC and DCSU (Data Compression and Storage Unit). Each block makes and corrects MSC's nonuniformity response. This paper shows the cause of nonuniformity error and the correction scheme of MSC system from the electronic point of view.

• Proceedings of the KSRS Conference
• /
• 2004.10a
• /
• pp.196-200
• /
• 2004

The purpose of this study is to examine the image­based atmospheric correction models using the data from Landsat Enhanced Thermal Mapper Plus (ETM+) that have quite similar spectral characteristics to the forthcoming Korea Multi-Purpose SATellite (KOMPSAT)-2 Multi-Spectral Camera (MSC), and the in-situ measured surface reflectance data during satellite overflight. The main advantage of this type of correction is that it does not require in-situ measurements during each satellite overflight. While substantial differences are present between Top-Of-the Atmosphere (TOA) reflectance and in-situ measurements, the results showed that Case 1 based on COST model gives most accurate results among three cases. The accuracy of Case 2 is very close to Case 1 and its values are smaller than in-situ data. No notable features appear between some bands in the Case 3 and in-situ data. It is expected from this study that if the current methods are applied to the IKONOS high resolution data, we will be able to develop the suitable atmospheric correction methods for MSC data.