• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.3
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• pp.349-354
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• 2007

To generate the template of a detected object and to track the overlapped object and the object covered by other objects correctly are important research problems in visual surveillance. The frame difference is not capable of generating the template of slowly moving object. To get around the drawback of the conventional frame difference, we propose a new algorithm for generating a template using adaptive 3-frame difference.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2007.04a
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• pp.357-360
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• 2007

물체를 추적하는데 있어서 추적하고자 하는 물체를 검출하여 템플릿을 만드는 것과 두 물체가 겹쳐지거나 다른 배경에 가려진 물체를 구분하여 추적하는 것은 물체 추적에 있어서 중요한 문제이다. 물체를 검출하여 템플릿을 만드는 방법으로 frame difference를 이용하면 천천히 움직이는 물체를 잘 구분할 수 없는 문제점이 있다. 이를 해결하기 위하여 본 논문에서는 adaptive 3-frame difference를 이용하여 정확한 물체의 템플릿을 생성하는 알고리즘을 제안한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.12
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• pp.2783-2797
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• 1997

This paper proposes a new motion estimation algorithm that employs matching in a variable search area. Instead of uisg a fixed search range for coarse motion estimation, we examine a varying search range, which is determined adaptively by the peak signal to noise ratio (PSNR) of the frame difference. The hexagonal matching method is one of the refined methods in image warping. It produces improved image quality, but it requires a large amount of computataions. The proposed adaptive partial matching method reduces computational complexity below about 50% of the hexagonal matching method, while maintaining the image quality comparable. The performance of two motion compensation methods, which combine the affine or bilinear transformation with the proposed motion estimation algorithm, is evaluated based on the following criteria:computtational complexity, number of coding bits, and reconstructed image quality. The quality of reconstructed images by the proposed method is substantially improved relative to the conventional BMA method, and is comparable to the full hexagonal matching method;in addition, computational complexity and the number of coding bits are reduced significantly.

• The Journal of the Acoustical Society of Korea
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• v.13 no.3
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• pp.16-24
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• 1994

A single channel adaptive noise canceling (ANC) technique is presented for removing effects of additive noise on the speech signal. The conventional method obtains a reference signal using the pitch estimated on a frame basis from the input speech. The proposed method, however, gets the reference signal using the delay estimated recursively on a sample by sample basis. To estimate the delay, we derive recursion formula of autocorrelation function and average magnitude difference function. The performance of the proposed method is evaluated for the speech signals distorted by the additive white Gaussian noise. Experimental results with normalized least mean square (NLMS) adaptive algorithm demonstrate that the proposed method improves the perceived speech quality quite well besides the signal-to-noise ratio.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.37 no.1
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• pp.55-63
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• 2000

This paper investigated the sub-region compression effect of the three dimensional DCT(3D-DCT) using the difference component(DC) of inter-frame in images. The proposed algorithm are the method that obtain compression effect to divide the information into subband after 3D-DCT, the data appear the type of cubic block(8${\times}$8${\times}$8) in eight difference components per unit. In the frequence domain that transform the eight differential component frames into eight DCT frames with components of both spatial and temporal frequencies of inter-frame, the image data are divided into frame component(8${\times}$8 block) of time-axis direction into 4${\times}$4 sub block in order to effectively obtain compression data because image components are concentrate in corner region with low-frequency of cubic block. Here, using the weight of sub block, we progressed compression ratio as consider to adaptive sub-region of low frequency part. In simulation, we estimated compression ratio, reconstructed image resolution(PSNR) with the simpler image and the complex image contained the higher frequency component. In the result, we could obtain the high compression effect of 30.36dB(average value in the complex-image) and 34.75dB(average value in the simple-image) in compression range of 0.04~0.05bpp.

• The KIPS Transactions:PartB
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• v.11B no.3
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• pp.247-256
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• 2004

In this paper, we propose the prediction search algorithm for block matching using the temporal/spatial correlation of the video sequence and the renter-biased property of motion vectors The proposed algorithm determines the location of a better starting point for the search of an exact motion vector using the point of the smallest SAD(Sum of Absolute Difference) value by the predicted motion vector from the same block of the previous frame and the predictor candidate pint in each search region and the predicted motion vector from the neighbour blocks of the current frame. And the searching process after moving the starting point is processed a adaptive search pattern according to the magnitude of motion vector Simulation results show that PSNR(Peak-to-Signal Noise Ratio) values are improved up to the 0.75dB as depend on the video sequences and improved about 0.05∼0.34dB on an average except the FS (Full Search) algorithm.

• The Journal of the Acoustical Society of Korea
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• v.18 no.6
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• pp.77-83
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• 1999

H.263 is an international standard of ITU-T that can makes the service such as video phone, video conference in the transmission line less than 64Kbps. This recommendation draft has used motion estimation/compensation, transform coding and quantizing methods. TMN5 used for the performance estimation of H.263 has fundamentally used DCT in transform coding method and presented quantizer for quantizing the DCT transform coefficient. This paper is presenting adaptive quantizer effectively able to quantize DCT coefficient considering the human visual sensitivity while the structure of TMN5 is maintaining. As quantizer that proposed DCT-based H.263 could make transmit more frame than TMN5 in a same transfer speed, it could lower the frame drop effect. And the luminance signal appeared the difference of -0.3 ～ +0.7dB in the average PSNR for the estimation of objective image quality and the chrominance signal appeared the improvement in about 1.5dB in comparision with TMN5. As a result it can attain the better image quality compared to TMN5 in the estimation of subjective image quality.

• Journal of the Korea Computer Graphics Society
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• v.3 no.2
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• pp.1-13
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• 1997

Two factors are required for a virtual reality system; realism and immersion. Since realism is determined primarily by the realistic image, objects in a virtual environment should be represented with details by their own characteristics. Also, reflection on light must be considered. On the other hand, immersion is defined as realistic movements and fast interactions. Thus, virtual environment should be rendered as fast as possibl. Regular frame rate should also be kept to make moves as intended by the user. In a complex virtual environment composed of objects with various levels, the appropriate level for individual object should be assigned according to the view point, in other words, the selection of level-of-detail is needed. In this paper, the problem of determining the levels of detail is formalized in terms of error, cost and L -distance. Error is defined as the difference between the current level image and the highest level image, cost as rendering time, and L-distance as the level difference between the previous and the current level. To solve this problem, a new method called the well-distributed adaptive algorithmis proposed.

• Journal of the Korean Institute of Rural Architecture
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• v.22 no.2
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• pp.1-8
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• 2020

This study is intended to derive the adaptive reuse techniques through the history and aspects of new construction, extension, repair, and other works, limited to the deep and narrow lots facing Seongan-gil and Nammun-gil in Nammun-ro 2 ga of Cheongju, the historic urban area. The results are as follows. 1) In the case of newly built reinforced concrete buildings, the central part of the top floor of the residence or all floors are opened to the open space(void) to facilitate lighting and ventilation. This is developed as a convection phenomenon due to the temperature difference from the slits between buildings, which affects the entire air flow of the block. 2) The buildings of extension and repair are composed of two-story masonry or steel frame, both the front store facing the road and the house on the back, but it looks like one because it is in contact with each other. If only a small gap between the front and rear buildings is restored to an external space or a space equipped with sun light, a small breath can be provided in lighting and ventilation. 3) The existing two-story wooden stores and houses have lost their external space due to repairs. With minimal intervention to restore the small courtyard, slits, and space under the eaves, it will not only improve lighting and ventilation, but also create a unique appearance as a segment of the elongated store.

• Journal of Broadcast Engineering
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• v.21 no.3
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• pp.349-356
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• 2016

In this paper, we propose an efficient assignment method that assigns quantization parameter (QP) in accordance with group of picture (GOP) structure given in HEVC encoder. Each video frames can have difference QP values based on given GOP configuration for HEVC encoding. Particularly, for important frames we can assign low QP values, and vice versa. However, there has not been thorough investigation on efficient QP assignment method by far. Even in HEVC reference software encoder, only monotonic QP assignment method is employed. Thus, the proposed method assign adaptive QP values to each GOP so that temporal dynamic activity between GOPs can be exploited. Through the experiment, the proposed method showed a 7.3% gain of compression performance in terms of BD-rate compared to HEVC test model (HM) in low-delay configuration, and outperformed the existing QP assignment study on average.