• Journal of the Korea Society of Computer and Information
• /
• v.16 no.6
• /
• pp.71-77
• /
• 2011

In this paper, we propose a learning based super resolution algorithm using local block for image enhancement of vehicle license plate. Local block is defined as the minimum measure of block size containing the associative information in the image. Proposed method essentially generates appropriate local block sets suitable for various imaging conditions. In particular, local block training set is first constructed as ordered pair between high resolution local block and low resolution local block. We then generate low resolution local block training set of various size and blur conditions for matching to all possible blur condition of vehicle license plates. Finally, we perform association and merging of information to reconstruct into enhanced form of image from training local block sets. Representative experiments demonstrate the effectiveness of the proposed algorithm.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.10 no.6
• /
• pp.165-174
• /
• 2010

TTG-blocks are concrete blocks designed to be paved around the bridge piers in order to protect the channel bed from local scour. In this study roughness coefficient of T.T.G- blocks are investigated through the hydraulic model test. And critical safety weight of TTG-blocks is derived in terms of Reynolds number for each individual block and group of linked blocks. Flume experiments show that a performance of TTG-blocks is effective to protect the river channel bed from local scour at bridge piers if it is assessed using with geotextile mat under blocks or designated gravels for filling in holes of blocks.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.41 no.6
• /
• pp.109-120
• /
• 2004

The current paper presents an effective deblocking algorithm for block-based coded images using singularity detection in Mallat wavelet transform. In block-based coded images. The local maxima of the wavelet transform modulus detect all singularities, including blocking artifacts, from multiscale edges. Accordingly, the current study discriminates between blocking artifacts and edges by estimating the Lipschitz regularity of the local maxima and removing the wavelet transform modulus of blocking artifacts. Experimental results showed that the performance of the proposed algorithm was objectively and subjectively superior.

• Journal of Broadcast Engineering
• /
• v.16 no.4
• /
• pp.647-656
• /
• 2011

Motion estimation using one-bit transform and two-bit transform reduces the complexity for computation of matching error; however, the peak signal-to-noise ratio (PSNR) is degraded. Modified 1BT (M1BT) and modified 2BT (M2BT) have been proposed to compensate degraded PSNR by adding conditional local search. However, these algorithms require many additional search points in fast moving sequences with a block size of $16{\times}16$. This paper provides more efficient search method by preparing candidate blocks using the number of non-matching points (NNMP) than the conditional local search. With this NNMP-based search, we can easily obtain candidate blocks with small NNMP and efficiently search final motion vector. Experimental results show that the proposed algorithm not only reduces computational complexity, but also improves PSNR on average compared with conventional search algorithm used in M1BT, M2BT and AM2BT.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.6
• /
• pp.2866-2871
• /
• 2011

In this study, computation method of tensile load which develops in tie-bar of reinforced earth, connection strength between tie-bar and eco-block and shear strength of the interface between two eco-blocks were verified by experiments. According to the test results of connection strength test, peak tensile load of D13 deformed bar were close to allowable tensile load of it for situation of infill with soil. Connection strengths of D10 and D13 deformed bars were greater than the allowable tensile load of those respectively for situation of infill with concrete. According to the test results of shear strength of the interface between two eco-blocks, shear resistance parameters, ${\alpha}_u$ and ��${\lambda}_u$ were evaluated as 1.7kN/m and 2$27.6^{\circ}$ respectively.

• Proceedings of the Korea Contents Association Conference
• /
• 2005.05a
• /
• pp.362-368
• /
• 2005

This paper is related to the fast block matching algorithm, especially a method for expanding the search pattern using the second local matching point in the adaptive hexagonal search. To reduce the local minima problem in fast motion estimation, the proposed method expands the search pattern by adding new searching points selected by using the second local matching point to conventional search pattern formed by the first local matching point in the adaptive hexagonal search. According to estimating the motion vector by applying block matching algorithm based on hexagonal search to the expanded search pattern, the proposed method can effectively carry out fast motion estimation to improve the performance in terms of compensated image quality.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.27 no.10A
• /
• pp.1011-1020
• /
• 2002

The current paper presents an effective deblocking algorithm for block-based coded images using singularity detection in a wavelet transform. In block-based coded images, the local maxima of a wavelet transform modulus detect all singularities, including blocking artifacts, from multiscale edges. Accordingly, the current study discriminates between a blocking artifact and an edge by estimation the Lipschitz regularity of the local maxima and removing the wavelet transform modulus of a blocking artifact that has a negative Lipschitz regularity exponent. Experimental results showed that the performance of the proposed algorithm was objectively and subjectively superior.

• Proceedings of the IEEK Conference
• /
• 2000.09a
• /
• pp.393-396
• /
• 2000

본 논문에서는 영상의 화소값으로부터 추출된 유사 특징점(quasi-feature point)을 이용한 이미지 모자이킹 알고리즘을 제안한다. 유사 특징점의 선택은 전역 정합(global matching)의 결과로부터 중첩된 영역을 4개의 부영역(sub-area)으로 분할하고, 각각의 분할된 부 영역에서 국부 분산(local variance)의 크기가 큰 블록을 선정, 이 블록의 중심 화소를 유사 특징점으로 선택한다. 유사 특징점에 대한 정합은 카메라 이동에 따른 왜곡(distortion)과 조명의 변화를 고려한 블록 정합 알고리즘(block matching algorithm)을 이용한다.

• Proceedings of the Korea Multimedia Society Conference
• /
• 2002.11b
• /
• pp.185-189
• /
• 2002

영상데이타의 효율적인 검색은 멀티미디어 데이터 베이스에 중요한 문제이다. 본 논문에서는 국부적인 블록 질감 특징을 바탕으로 한 새로운 영상 검색 방법을 제안한다. 본 논문에서는 영상을 NxM크기의 블록으로 나누어 GLCM을 구한 후, 이에 대한 통계적 질감 특징인 블록 질감 히스토그램을 생성하여 영상 검색에 사용한다. 실험을 통한 성능 평가에서 제안한 방법이 GLCM을 이용한 기존의 방법보다 Recall과 Precision이 약 3～8%의 향상을 보였다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.30 no.6C
• /
• pp.465-474
• /
• 2005

In this paper, a directional reconstruction of lost block in image over noisy channel is presented. DCT coefficients or pixel values in the lost blocks are recovered by using the linear interpolation with available neighboring blocks that are adaptively selected by the directional measure that are composed of the DDC (Difference of DC opposite blocks)and SAC(Similarity of AC opposite blocks) between opposite blocks around lost blocks. The proposed directional recovery method is effective for the strong edge and texture regions because we do not make use of the fixed 4-neighboring blocks but exploit the varying neighboring blocks adaptively by the directional information in the local image. In this paper, we describe the novel directional measure(CDS: Combination of DDC and SAC) composed of the DDC and the SAC and select the usable block to recover the lost block with the directional measure. The proposed method shows about 0.6dB PSNR improvement in average compared to the conventional methods.