• Title/Summary/Keyword: Block classification

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An Effective Postprocessing Algorithm for Block Encoded Images Using Adaptive Filtering and Interpolation (적응적 필터링과 보간법을 이용한 블록기반 압축영상의 효율적인 후처리 알고리듬)

  • Park, Kyung-Nam
    • Journal of Korea Society of Industrial Information Systems
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    • v.12 no.1
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    • pp.39-45
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    • 2007
  • In this paper, we present a new postprocessing algorithm using interpolation and signal adaptive filter according to the each block characteristic which is acquired in block classification process. We applied blocking artifact reduction algorithm for four neighbor low frequency block and ringing artifacts is removed with preserving edges by applying a signal adaptive filter in high frequency block based on edge map. The computer simulation results confirmed a better performance by the proposed method in both the subjective and objective image qualities.

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A Study on the Repair Welding Methods for Cylinder Block of Diesel Engines (디젤기관 실린더 블록의 보수용접법에 관한연구)

  • 김종호
    • Journal of Advanced Marine Engineering and Technology
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    • v.23 no.3
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    • pp.331-337
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    • 1999
  • Cracks on the cylinder block of diesel engines will often happen due to cyclic load and thermal stress. According to the Classification Societies' rules welding reparis of cylinder block made of cast irons are generally not permitted. However such welding repairs became inevitable taking enormous cost and time for their renewal into consideration. In this study repair welding methods for the clinder blocks made of gray cast irons were reviewed and the tests of their welds were carried out in order to purpose the repair welding meth-ods of packing seat and o-ring seat of cylinder block and apply them to the practice. The following conclusions are botained :1 The tensile strength of weld of cast iron more than that of base metal can be obtained by means of preheating keeping temperature above $100^{\circ}C$ between welding pass-es preventing slag inclusion peening and cramping weld metal by studs. 2. The suspected crack by a magnetic particle test due to different magnetic permeability can be identified which are not associated with a mechanical discotinuity.

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Image Compression using Validity and Zero Coefficients by DCT(Discrete Cosine Transform) (DCT에서 유효계수와 Zero계수를 이용한 영상 압축)

  • Kim, Jang Won;Han, Sang Soo
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.1 no.3
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    • pp.97-103
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    • 2008
  • In this paper, $256{\times}256$ input image is classified into a validity block and an edge block of $8{\times}8$ block for image compression. DCT(Discrete Cosine Transform) is executed only for the DC coefficient that is validity coefficients for a validity block. Predict the position where a quantization coefficient becomes 0 for an edge block, I propose new algorithm to execute DCT in the reduced region. Not only this algorithm that I proposed reduces computational complexity of FDCT(Forward DCT) and IDCT(Inverse DCT) and decreases encoding time and decoding time. I let compressibility increase by accomplishing other stability verticality zigzag scan by the block size that was classified for each block at the time of huffman encoding each. In addition, the algorithm that I suggested reduces Run-Length by accomplishing the level verticality zigzag scan that is good for a classified block characteristic and, I offer the compressibility that improved thereby.

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Multi-granular Angle Description for Plant Leaf Classification and Retrieval Based on Quotient Space

  • Xu, Guoqing;Wu, Ran;Wang, Qi
    • Journal of Information Processing Systems
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    • v.16 no.3
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    • pp.663-676
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    • 2020
  • Plant leaf classification is a significant application of image processing techniques in modern agriculture. In this paper, a multi-granular angle description method is proposed for plant leaf classification and retrieval. The proposed method can describe leaf information from coarse to fine using multi-granular angle features. In the proposed method, each leaf contour is partitioned first with equal arc length under different granularities. And then three kinds of angle features are derived under each granular partition of leaf contour: angle value, angle histogram, and angular ternary pattern. These multi-granular angle features can capture both local and globe information of the leaf contour, and make a comprehensive description. In leaf matching stage, the simple city block metric is used to compute the dissimilarity of each pair of leaf under different granularities. And the matching scores at different granularities are fused based on quotient space theory to obtain the final leaf similarity measurement. Plant leaf classification and retrieval experiments are conducted on two challenging leaf image databases: Swedish leaf database and Flavia leaf database. The experimental results and the comparison with state-of-the-art methods indicate that proposed method has promising classification and retrieval performance.

An Efficient Block Segmentation and Classification Method for Document Image Analysis Using SGLDM and BP (공간의존행렬과 신경망을 이용한 문서영상의 효과적인 블록분할과 유형분류)

  • Kim, Jung-Su;Lee, Jeong-Hwan;Choe, Heung-Mun
    • The Transactions of the Korea Information Processing Society
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    • v.2 no.6
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    • pp.937-946
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    • 1995
  • We proposed and efficient block segmentation and classification method for the document analysis using SGLDM(spatial gray level dependence matrix) and BP (back Propagation) neural network. Seven texture features are extracted directly from the SGLDM of each gray-level block image, and by using the nonlinear classifier of neural network BP, we can classify document blocks into 9 categories. The proposed method classifies the equation block, the table block and the flow chart block, which are mostly composed of the characters, out of the blocks that are conventionally classified as non-character blocks. By applying Sobel operator on the gray-level document image beforebinarization, we can reduce the effect of the background noises, and by using the additional horizontal-vertical smoothing as well as the vertical-horizontal smoothing of images, we can obtain an effective block segmentation that does not lead to the segmentation into small pieces. The result of experiment shows that a document can be segmented and classified into the character blocks of large fonts, small fonts, the character recognigible candidates of tables, flow charts, equations, and the non-character blocks of photos, figures, and graphs.

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Adaptive Block Truncation Coding Based on Gradient Information (경사도를 이용한 적응 구획 절단 부호화)

  • 신용달;이봉락;이건일
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.10
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    • pp.1546-1552
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    • 1993
  • We proposed an adaptive block truncation coding(BTC) using gradient and a new initial value. We used gradient of sobel operator as a new category classification coefficient to reduce Jagged appearance at edge part. We defined a new initial value to reduce large quantization error in the 4-level quantizer block including edge part. By computer simulations, we showed that the proposed method less computation load, reduced jagged appearance at edge part, also improved PSNR more than the conventional adaptive BTC.

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An adaptive search area adjustment of the block-matching algorithm for motion estimation (블록 정합 알고리즘을 이용한 움직임 추정의 적응적 탐색 영역 조정 기법)

  • 오황석;서영호;이흥규
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.8B
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    • pp.1109-1118
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    • 2001
  • 움직임 추정 및 보상 기법은 비디오 코딩 응용 분야에서 일반적으로 많이 사용되는 방법이나 많은 계산량으로 인하여 실시간 움직임 추정이 쉽지 않다. 본 논문에서는 낮은 비트율 비디오 코딩을 위한 전역 탐색 기법의 블록 정합 알고리즘의 복잡도를 줄이기 위하여 탐색 영역을 적응적으로 줄여주는 기법을 제안한다. 제안된 기법은 연속한 비디오 프레임에서 변위된 블록의 차이(displaced block difference)와 블록 구분 정보(block classification information) 등과 같은 상관성을 이용하여 탐색 영역의 범위를 적응적으로 조정한다. 실험을 통하여 제안된 기법이 전역 탐색 영역 기법과 비교하여 계산량에서 1/2의 계산량 이득이 있으며, 비슷한 MSE(mean square error) 성능을 가짐을 보인다.

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Case Study of Chronic Headache Patient by Oriental Medical Treatment (한방치료로 호전된 만성 두통 환자 치험 1례)

  • Bang, Chang-Ho;Yun, Jong-Min
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.24 no.6
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    • pp.1105-1110
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    • 2010
  • The purpose of this case study is to report the effect of oriental medical treatment on chronic tension-type headache. Despite the patient was treated by cervical nerve block for headache, headache was not improved. We diagnosed chronic tension-type headache according to ICHD-II(The International Classification of Headache Disorders) and Qi deficiency, dampness and phlegm by oriental differential diagnosis of symptom and signs. We applied herbal medicine, acupuncture, moxibustion and cupping therapy for hospitalization(7 days). Oriental medical treatment may have effective results in treating chronic tension-type headache that was not improved by cervical nerve block treatment. But this is a single case study, so further case-series research should be compiled.

Hybrid Deinterlacing Algorithm with Motion Vector Smoothing

  • Khvan, Dmitriy;Jeon, Gwanggil;Jeong, Jechang
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2012.07a
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    • pp.262-265
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    • 2012
  • In this paper we propose a new deinterlacing method with block classification and motion vector smoothing. The proposed method classifies a block, then depending on the region it belongs to, the motion estimation or line averaging is applied. To classify a block its variance is calculated. Then, for those blocks that belong to simple non-texture region the line averaging is done while motion estimation is applied to complex region. The motion vector field is smoothed using median filter what yields more accurate interpolation. In the experiments for the subjective evaluation, the proposed method bas shown satisfying results in terms of computation time consumption and peak signal-to-noise ratio. Due to the simplicity of the algorithm computation time was drastically decreased.

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Partial-Thickness Rotator Cuff Tears

  • Shin, Keun-Man
    • The Korean Journal of Pain
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    • v.24 no.2
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    • pp.69-73
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    • 2011
  • Although the incidence of partial-thickness rotator cuff tears (PTRCTs) was reported to be from 13% to 32% in cadaveric studies, the actual incidence is not yet known. The causes of PTRCTs can be explained by either extrinsic or intrinsic theories. Studies suggest that intrinsic degeneration within the rotator cuff is the principal factor in the pathogenesis of rotator cuff tears. Extrinsic causes include subacromial impingement, acute traumatic events, and repetitive microtrauma. However, acromially initiated rotator cuff pathology does not occur and extrinsic impingement does not cause pathology on the articular side of the tendon. An arthroscopic classification system has been developed based on the location and depth of the tear. These include the articular, bursal, and intratendinous areas. Both ultrasound and magnetic resonance image are reported with a high accuracy of 87%. Conservative treatment, such as subacromial or intra-articular injections and suprascapular nerve block with or without block of the articular branches of the circumflex nerve, should be considered prior to operative treatment for PTRCTs.