• Title/Summary/Keyword: Image Intensity

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Identification of Transformed Image Using the Composition of Features

  • Yang, Won-Keun;Cho, A-Young;Cho, Ik-Hwan;Oh, Weon-Geun;Jeong, Dong-Seok
    • Journal of Korea Multimedia Society
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    • v.11 no.6
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    • pp.764-776
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    • 2008
  • Image identification is the process of checking whether the query image is the transformed version of the specific original image or not. In this paper, image identification method based on feature composition is proposed. Used features include color distance, texture information and average pixel intensity. We extract color characteristics using color distance and texture information by Modified Generalized Symmetry Transform as well as average intensity of each pixel as features. Individual feature is quantized adaptively to be used as bins of histogram. The histogram is normalized according to data type and it is used as the signature in comparing the query image with database images. In matching part, Manhattan distance is used for measuring distance between two signatures. To evaluate the performance of the proposed method, independent test and accuracy test are achieved. In independent test, 60,433 images are used to evaluate the ability of discrimination between different images. And 4,002 original images and its 29 transformed versions are used in accuracy test, which evaluate the ability that the proposed algorithm can find the original image correctly when some transforms was applied in original image. Experiment results show that the proposed identification method has good performance in accuracy test. And the proposed method is very useful in real environment because of its high accuracy and fast matching capacity.

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Global Intensity Compensation using Mapping Table (맵핑 테이블을 이용한 전역 밝기 보상)

  • Oh, Sang-Jin;Lee, Ji-Hong;Ko, Yun-Ho
    • Proceedings of the KIEE Conference
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    • 2006.04a
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    • pp.15-17
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    • 2006
  • This paper presents a new global intensity compensation method for extracting moving object in a visual surveillance system by compensating time variant intensity changes of background region. The method that compensates a little changes of intensity due to time variant illumination change and automatic gain control of camera is called global intensity compensation. The proposed method expresses global intensity change with a mapping table to describe complex form of intensity change while the previous method models this global intensity change with a simple function as a straight line. The proposed method builds the mapping table by calculating the cross histogram between two images and then by selecting an initial point for generating the mapping table by using Hough transform applied to the cross histogram image. Then starting from the initial point, the mapping table is generated according to the proposed algorithm based on the assumption that reflects the characteristic of global intensity change. Experimental results show that the proposed method makes the compensation error much smaller than the previous GIC method

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Bilateral Symmetry Averaging and Simple Regression Analysis for Robust Face Detection Against Illumination Variation (조명 변화에 강인한 얼굴 검출을 위한 좌우대칭 평균화와 단순회귀분석 보정기법)

  • Cho, Chi-Young;Kim, Soo-Hwan
    • The Journal of the Korea Contents Association
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    • v.6 no.12
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    • pp.21-28
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    • 2006
  • In a face detection system based on template matching, histogram equalization or log transform is applied to an input image for the intensity normalization and the image improvement. It is known that they are noneffective in improving an image with intensity distortion by illumination variation. In this paper, we propose an efficient image improvement method using a simple regression analysis combined with a bilateral symmetry average for images with intensity distortion by illumination variation. Experimental results show that our method delivers the detection performance better than previous methods and also remarkably reduces the number of face candidates.

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Performance Evaluations of the Interpolation Methods Under the various illumination intensities and its Application to the Adaptive Interpolation for Image Sensors (이미지센서를 위한 조도에 따른 보간 기법의 성능 평가와 이를 이용한 가변적 보간 기법)

  • Kim, Byung-Su;Paik, Doo-Won
    • Journal of Internet Computing and Services
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    • v.9 no.1
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    • pp.171-177
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    • 2008
  • In this paper we compared the performance of interpolation algorithms for Bayer patterned image sensors under the various illumination intensities. As the interpolation algorithms, we used bilinear color interpolation and adaptive fuzzy color interpolation and our experimentation shows that performance of interpolation algorithms depend on the lighting conditions; in low intensity of illumination, bilinear color interpolation with median filter performs best, in high intensity of illumination, adaptive fuzzy color interpolation performs best, and in between bilinear color interpolation performs best. This study suggested an interpolation scheme which applies different interpolation algorithm according to the intensity of the input image, resuting in the better image quality.

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The Optimal Signal Intensity according to Image Scale Reset of MRI (자기공명영상의 image scale 재설정에 따른 최적의 영상신호 표준화)

  • Lee, Ho-Beom;Choi, Kwan-Woo;Son, Soon-Yong
    • The Journal of the Korea Contents Association
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    • v.17 no.12
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    • pp.266-271
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    • 2017
  • In this study, we tried to improve the reproducibility of signal intensity by applying DOTS method. The study was conducted on 30 patients who had undergone hepatic screening because of poor reproducibility and decreased signal intensity. The images were acquired before and after injection of contrast media and then post-processed by DOTS methods. Signal intensity was compared and evaluated. The results showed that the signal intensity of the images was 183.3% ($1038.0{\pm}70.7$ before application, $2940.7{\pm}179.6$ after application) and 1118.4% ($444.1{\pm}92.4$, $5410.5{\pm}168.4$ after application). This is a significant improvement in the fact that the reproducibility of MRI) was changed by the DOTS method, which is a post-processing method.

The Turbidity Measured by Division Image Analysis in Flow Type Sample (분할화상분석에 의한 흐름 형태 시료의 탁도 측정)

  • Park, Jong-Ho;Park, Soo-Haeng;Ryu, Min-Su
    • Applied Chemistry for Engineering
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    • v.20 no.6
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    • pp.681-684
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    • 2009
  • The turbidity of flow type samples has a nonlinear relation to brightness of laser scattered light, but the shape of images in laser scattered light is different from each turbidity samples. The turbidity measurement will be easy if it uses a pattern of images in laser scattered light. But the excessive analysis load comes from the turbidity measured by red, green, blue intensity (intensity) of all pixels of images in laser scattered light. Therefore the images in laser scattered light were divided by appropriate block to decrease excessive analysis load. The shape of divided images in laser scattered light was different from each turbidity sample. The real turbidity has a linear relation to turbidity measured by the artificial neural network learned with the intensity of divided images in laser scattered light and turbidity.

Analysis of Signal Intensity in Choroid Plexuses by Diffusion Weighted Imaging (확산강조영상의 검사기법에 따른 맥락얼기의 신호강도 분석)

  • Oh, JongKap
    • Journal of the Korean Society of Radiology
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    • v.7 no.4
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    • pp.265-269
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    • 2013
  • This report aims at picturing out the clinical usefulness by analyzing the signal intensity in choroid plexuses which produce cerebrospinal fluids by diffusion weighted imaging. At first, subjects were chosen among the patients who showed high in signal intensity by diffusion weighted imaging. The subjects were taken another test by fluid attenuated inversion recovery diffusion weighted echo planer image(FLAIR-DW-EPI) the signals of fluid attenuation. And it was found that there are differences between the signal intensities of the two methods, which showed that the signal intensity in FLAIR-DW-EPI is equal to or low than, that in the Brain. By this, it is felt that it is helpful to diagnose the disease in choroid plexus by testing another more with FLAIR-DW-EPI methods the patients who showed high in signal intensity in choroid plexus by $T2^*$ diffusion weighted echo planer image($T2^*$-DW-EPI).

Infra-Red Reflectography Based Mural Underdrawing Mosaicing Technique (적외선 리플렉토그래피 기반 벽화 밑그림 영상 모자익 기법)

  • Lee, Tae-Seong;Gwon, Yong-Mu;Go, Han-Seok
    • Proceedings of the KIEE Conference
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    • 2003.11b
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    • pp.191-194
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    • 2003
  • In this paper, we propose a new accurate and robust image mosaic technique of the mural underdrawing taken from the infra-red camera, which is based on multiple image registration and adaptive blending technique. The image mosaicing methods which have been developed so far have the following deficits. It is hard to generate a high resolution image when there are regions that do not have features or intensity gradients, and there is a trade-off in overlapping region site in view of registration and blending. We consider these issues as follows. First, in order to mosaic Images with neither noticeable features nor intensity gradients, we use a Projected supplementary pattern and pseudo color image for features in the image Pieces which are registered. Second, we search the overlapping region size with minimum blending error between two adjacent images and then apply blending technique to minimum error overlapping region. Finally, we could find our proposed method is more effective and efficient for image mosaicing than conventional mosaic techniques and also is more adequate for the application of infra-red mural underdrawing mosaicing. Experimental results show the accuracy and robustness of the algorithm.

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Dynamic LEED System Developed by Using Image Precessing (화상처리를 이용한 저에너지 전자회절 시스템(LEED) 개발)

  • 김재훈;김동준;이승민;김재성;변대현;민항기
    • Journal of the Korean Vacuum Society
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    • v.2 no.4
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    • pp.515-519
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    • 1993
  • Image processin software is developed to get spot intensity form the frame of a LEEd pattern obtained by using a CCD Camera and a frame grabber. Imporved algorithm for more reasonable background substraction is implemented in this software . I/V Charateristicsof some spots form Cu(001) suface are collected . These results are compared with those of Davis and Noonan and found to be consistent with the latter results. This software is also applied to meausre RHEEd spot intensity oscillatin, and gives clear oscillations very easily.

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An Effective Extraction Algorithm of Pulmonary Regions Using Intensity-level Maps in Chest X-ray Images (흉부 X-ray 영상에서의 명암 레벨지도를 이용한 효과적인 폐 영역 추출 알고리즘)

  • Jang, Geun-Ho;Park, Ho-Hyun;Lee, Seok-Lyong;Kim, Deok-Hwan;Lim, Myung-Kwan
    • Journal of Korea Multimedia Society
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    • v.13 no.7
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    • pp.1062-1075
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    • 2010
  • In the medical image application the difference of intensity is widely used for the image segmentation and feature extraction, and a well known method is the threshold technique that determines a threshold value and generates a binary image based on the threshold. A frequently-used threshold technique is the Otsu algorithm that provides efficient processing and effective selection criterion for choosing the threshold value. However, we cannot get good segmentation results by applying the Otsu algorithm to chest X-ray images. It is because there are various organic structures around lung regions such as ribs and blood vessels, causing unclear distribution of intensity levels. To overcome the ambiguity, we propose in this paper an effective algorithm to extract pulmonary regions that utilizes the Otsu algorithm after removing the background of an X-ray image, constructs intensity-level maps, and uses them for segmenting the X-ray image. To verify the effectiveness of our method, we compared it with the existing 1-dimensional and 2-dimensional Otsu algorithms, and also the results by expert's naked eyes. The experimental result showed that our method achieved the more accurate extraction of pulmonary regions compared to the Otsu methods and showed the similar result as the naked eye's one.