• Journal of Korea Multimedia Society
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• v.18 no.12
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• pp.1453-1461
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• 2015

Since digital images and videos are rapidly increasing in the internet with the spread of mobile computers and smartphones, research on image retrieval has gained tremendous momentum. Color, shape, and texture are major features used in image retrieval. Especially, color information has been widely used in image retrieval, because it is robust in translation, rotation, and a small change of camera view. This paper proposes a new method for histogram refinement based on local color difference. Firstly, the proposed method converts a RGB color image into a HSV color image. Secondly, it reduces the size of color space from 256³ to 32. It classifies pixels in the 32-color image into three groups according to the color difference between a central pixel and its neighbors in a 3x3 local region. Finally, it makes a color difference vector(CDV) representing three refined color histograms, then image retrieval is performed by the CDV matching. The experimental results using public image database show that the proposed method has higher retrieval accuracy than other conventional ones. They also show that the proposed method can be effectively applied to search low resolution images such as thumbnail images.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1986.10a
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• pp.56-58
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• 1986

This paper propose a conversion method to reduce prediction error produced when PRA(Pel Recursive Algorithm) motion estimation method is used in real image. The method is th get a spatial difference image from a given raw image and then to apply any PRA method to the difference image. The algorithm proposed in this paper is compared with several algorithm including the ubiquitious Netravali and Robbins` based on the performance and the hardware complexity. Computer simulation shows that the difference image conversion method is about 4.5dB better than the other algorithm with regard to prediction error power.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.4
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• pp.1714-1729
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• 2018

Change detection of remote sensing images is a profound challenge in the field of remote sensing image analysis. This paper proposes a novel change detection method for bitemporal remote sensing images based on feature fusion and fuzzy c-means (FCM). Different from the state-of-the-art methods that mainly utilize a single image feature for difference image construction, the proposed method investigates the fusion of multiple image features for the task. The subsequent problem is regarded as the difference image classification problem, where a modified fuzzy c-means approach is proposed to analyze the difference image. The proposed method has been validated on real bitemporal remote sensing data sets. Experimental results confirmed the effectiveness of the proposed method.

• Journal of Institute of Control, Robotics and Systems
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• v.8 no.10
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• pp.874-880
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• 2002

A number of techniques have been proposed for 3D display using view-difference of two eyes. These methods do not express enough reality like real world. The display images have to change according to the position of a viewer to improve reality. In this paper, we present an approach for generating intermediate image between two different view images by applying new image interpolation algorithm The interpolation algorithm is designed to cope with complex shapes. The proposed image interpolation algorithm generates rotated image about vertical axes by any angle from base images. Each base image that was obtained from CCD camera has an view-angle difference of $3^{\circ}C$, $5.5^{\circ}C$, $^{\circ}C$, $22^{\circ}C$, and $45^{\circ}C$. The proposed into mediate image generation method uses the geometric analysis of image and depth information through the block-based matching method.

• Journal of Korea Multimedia Society
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• v.21 no.9
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• pp.1044-1051
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• 2018

In this paper, we propose a new method to improve low light image. In order to improve the image quality of a night image with a moving object as much as the quality of a daytime image, the following tasks were performed. Firstly, we reduce the noisy of the input night image and improve the night image by the tone mapping method. Secondly, we segment the input night image into a foreground with motion and a background without motion. The motion is detected using both the difference between the current frame and the previous frame and the difference between the current frame and the night background image. The background region of the night image takes pixels from corresponding positions in the daytime image. The foreground regions of the night image take the pixels from the corresponding positions of the image which is improved by the tone mapping method. Experimental results show that the proposed method can improve the visual quality more clearly than the existing methods.

• Journal of Korea Multimedia Society
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• v.13 no.6
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• pp.833-840
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• 2010

In this paper a method for detecting and extracting the face from the image in YCbCr spaceis proposed. The face region is obtained from the complex original image by using the difference method and the face color information is taken from the reduced face region throughthe Ellipse clustering method. The experimental results showed that the proposed method can efficiently detect and extract the face from the original image under the general light intensity except for low luminance.

• Journal of Welding and Joining
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• v.22 no.6
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• pp.43-49
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• 2004

In this study, a visual sensor system which can detect I-butt weld joint with height variation and includes a seam tracking algorithm was investigated. Three-dimensional position of an object can be acquired by using the method of distance measurement, i.e., an optical trigonometry which results from the spatial relations between the camera, the object and the structured light by a visible laser. Effects of laser intensity and iris number for the image quality as well as object material were investigated for the optical system design. For the image processing, a region of interest is defined from the whole image and a line image of laser is drew by using the gray level difference in the image. From the drew laser line, the weld joint can be recognized in searching the biggest point position calculated from the central difference method. Through a series of welding experiments, a good tracking performance was confirmed under GMA welding.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.625-628
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• 2007

We present an efficient and robust technique to estimate the velocity of moving targets from a single SAR image. In SAR images, azimuth image shift is a well known phenomenon, which is observed in moving targets having slant-range velocity. Most methods estimated the velocity of moving targets from the distance difference between the road and moving targets or between ship and the ship wake. However, the methods could not be always applied to moving targets because it is difficult to find the road and the ship wake. We adopted a method estimating the velocity of moving targets from azimuth differentials of range-compressed image. This method is based on an assumption that Doppler center frequency shift of moving target causes a phase difference in azimuth differential values. The phase difference is linearly distorted by Doppler rate due to the geometry of SAR image. The linear distortion is eliminated from phase removal procedure, and the constant phase difference is estimated. Finally, range velocity estimates for moving targets are retrieved. This technique is tested using an ENVISAT ASAR image in which several unknown ships are presented. The theoretical accuracy of this technique is discussed by SAR simulation. The advantages and disadvantages of this method over the conventional method are also discussed.

• The KIPS Transactions:PartB
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• v.14B no.5
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• pp.361-368
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• 2007

In this paper, we propose a smoke detection method which is based on block-wise difference of image frames in video. Our proposed method is composed of three steps which are (a) the detection step of the changed regions against the background, (b) the background update step, and (c) the smoke determination step from the changed regions. We first construct the block mean Image of frames in video. And to extract the changed regions against the background, we use a block-wise difference between background's block mean image and a current input frame's block mean image. After applying projections in block-based difference images, we can determine the changed regions as rectangles using projections of difference images. we propose a update scheme of background's block mean image using the projections. We decide the smoke region using the femoral statistics of the central position and YUV color in the changed region.

• Journal of the Korea Fashion and Costume Design Association
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• v.2 no.1
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• pp.21-35
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• 2000

The purpose of this study was to evaluate the preference of image for modern application of Korean traditional patterns. A survey was conducted using the randomly selected 292 undergraduate women students of Taegu city. The degree of interest and preference in Korean traditional style or something like that had measured by 5 scale method. And then they had two groups which are interest/non-interest group, and preference/non-preference group in Korean traditional style. Also, preference of Korean traditional patterns was measured by 5 scale method. The image of Korean traditional patterns consisted of semantic differential scales. Analysis was by frequency, percentage, and mean. For difference of groups analysis was by t-test. The results were as follows:1. For the survey, 53.8% showed the interest and 40.4% did the preference for the traditional patterns. There was the positive correlation(0.782) between the degree of the interest and preference. 2. Among twenty traditional patterns, the patterns of plants and nature were very preferred, but the patterns of geometrical things was not preferred. 3. For the nature pattern, the image seemed to be elegant and feminine(womanly). For the plant pattern, the image seemed to be feminine, neat, weak, light and mild. For the animal pattern, the image seemed to be heavy, gorgeous, deluxe, virile(manly), strong and active. Last, for the geometrical pattern, the image seemed to be elegant, deluxe, rigid and strong. 4. Between the interest／non­interest groups, there was the significant difference in pattern of cloud, mountain, lotus flower, plum blossoms, orchid, dragon, chinese phoenix and bogy. Especially, for the orchid pattern, the preference difference between these groups was large. 5. For the plant pattern, the image difference between these groups was very large as the elegant-rustic image. Especially, the interest group evaluated as the elegant image. 6. Between the preference／non­preference groups, there was the strongly significant difference in the preference for the orchid pattern. 7. For the geometrical pattern, the image difference between these groups was very large as the mild­cold image. Especially, the preference groups evaluated as the cold image.