• Title, Summary, Keyword: 영상 압축

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Technology Development for Improving Animation Performance Based on Train Route Patterns (열차 경로 패턴기반 애니메이션 성능 개선 기술 개발)

  • Lee, Duk-Hee;Yang, Won-Mo;Kim, Yong-Il;Yang, Yun-Hee;Shin, Yong-Tae
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.11 no.5
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    • pp.136-146
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    • 2012
  • As information technology used for simulation and virtual reality developed, there is a growing interest in animation technologies which will effectively deliver simulation results to users. Various efforts have been made to improve animation performance, like playback quality and speed, input-output speed and storage space reduction. However, earlier studies generally focused on image compression frame by frame. To significantly improve storage space and playback speed, animation data should be vectorized. Also, spatial and temporal duplication have to be removed. In this study, animation data structure was improved fundamentally through establishment of hierarchy and vectorization. Also Spatial and temporal duplication of animation data was removed through vectorization based on train route. As a result, storage space was reduced, input-output speed and playback speed were considerably improved. According to the test, additional Patternization which followed vectorization brought reduction of over 80% in storage space and input-output speed was quadrupled. Patternization technology can be used as a proper storage method of animation data, and can provide user-specific animation by small data transmission.

A Fast and Dynamic Region-of-Interest Coding Method using the Adaptive Code-Block Discrimination Algorithm in JPEG2000 Images (JPEG2000 이미지에서 적응적 코드블록 판별 알고리즘을 이용한 동적 고속 관심영역 코딩 방법)

  • Kang, Ki-Jun;Seo, Yeong-Geon;Park, Jae-Heung;Yoo, Chang-Yeul;Park, Soon-Hwa;Lee, Jum-Suk;Lee, Bu-Kwon
    • The KIPS Transactions:PartB
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    • v.14B no.5
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    • pp.321-328
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    • 2007
  • In this paper, we propose a fast and dynamic Region-of-Interest coding method using the adaptive code-block discrimination algorithm in JPEG2000 images which complements the implicit ROI coding method and the modified implicit ROI coding method. For reducing the time of discriminating the code block, the proposed method estimates the characteristics of the shape of ROI and makes the shape of boundaries, and classifies the patterns of each code block. The method improves the preferred processing and loss of wavelet coefficients of background within the ROI code blocks by adaptively classifying the code blocks with the percentage of content of the wavelet coefficients using the thresholds of ROI and background. Also, the priority control of wavelet coefficients of background within ROI code block supports the rapid ROI coding by processing in batch based on patterns unlike the existing methods that process with unit of wavelet coefficients. To show the usefulness of this method, we compared this to the existing methods. There is no difference in performance, but we confirmed very speedy in processing time.

Analysis of Subsurface Geological Structures and Geohazard Pertinent to Fault-damage in the Busan Metropolitan City (부산시 도심지의 지하 지질구조와 단층손상과 관련된 지질위험도 분석)

  • Son, Moon;Lee, Son-Kap;Kim, Jong-Sun;Kim, In-Soo;Lee, Kun
    • Economic and Environmental Geology
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    • v.40 no.1
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    • pp.87-101
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    • 2007
  • A variety of informations obtained from satellite image, digital elevation relief map (DEM), borehole logging, televiewer, geophysical prospecting, etc were synthetically analyzed to investigate subsurface geological and structural characteristics and to evaluate geohazard pertinent to fault-damage in the Busan metropolitan city. It is revealed that the geology is composed of the Cretaceous andesitic$\sim$dacitic volcanics, gabbro, and granitoid and that at least three major faults including the Dongrae fault are developed in the study area. Based on characteristics of topography, fault-fractured zone, and isobath maps of the Quaternary sediments and weathered residuals of the basement, the Dongrae fault is decreased in its width and fracturing intensity of damaged zone from south toward north, and the fault is segmented around the area between the Seomyeon and Yangieong junctions. Meanwhile, we drew a geohazard sectional map using the five major parameters that significantly suggest damage intensity of basement by fault, i.e. distance from fault core, TCR, RQD, uniaxial rock strength, and seismic velocity of S wave. The map is evaluated as a suitable method to express the geological and structural characteristics and fault-damaged intensity of basement in the study area. It is, thus, concluded that the proposed method can contribute to complement and amplify the capability of the present evaluation system of rock mass.

An Efficient Bitmap Indexing Method for Multimedia Data Reflecting the Characteristics of MPEG-7 Visual Descriptors (MPEG-7 시각 정보 기술자의 특성을 반영한 효율적인 멀티미디어 데이타 비트맵 인덱싱 방법)

  • Jeong Jinguk;Nang Jongho
    • Journal of KIISE:Computer Systems and Theory
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    • v.32 no.1
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    • pp.9-20
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    • 2005
  • Recently, the MPEG-7 standard a multimedia content description standard is wide]y used for content based image/video retrieval systems. However, since the descriptors standardized in MPEG-7 are usually multidimensional and the problem called 'Curse of dimensionality', previously proposed indexing methods(for example, multidimensional indexing methods, dimensionality reduction methods, filtering methods, and so on) could not be used to effectively index the multimedia database represented in MPEG-7. This paper proposes an efficient multimedia data indexing mechanism reflecting the characteristics of MPEG-7 visual descriptors. In the proposed indexing mechanism, the descriptor is transformed into a histogram of some attributes. By representing the value of each bin as a binary number, the histogram itself that is a visual descriptor for the object in multimedia database could be represented as a bit string. Bit strings for all objects in multimedia database are collected to form an index file, bitmap index, in the proposed indexing mechanism. By XORing them with the descriptors for query object, the candidate solutions for similarity search could be computed easily and they are checked again with query object to precisely compute the similarity with exact metric such as Ll-norm. These indexing and searching mechanisms are efficient because the filtering process is performed by simple bit-operation and it reduces the search space dramatically. Upon experimental results with more than 100,000 real images, the proposed indexing and searching mechanisms are about IS times faster than the sequential searching with more than 90% accuracy.

Motion Estimation and Mode Decision Algorithm for Very Low-complexity H.264/AVC Video Encoder (초저복잡도 H.264 부호기의 움직임 추정 및 모드 결정 알고리즘)

  • Yoo Youngil;Kim Yong Tae;Lee Seung-Jun;Kang Dong Wook;Kim Ki-Doo
    • Journal of Broadcast Engineering
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    • v.10 no.4
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    • pp.528-539
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    • 2005
  • The H.264 has been adopted as the video codec for various multimedia services such as DMB and next-generation DVD because of its superior coding performance. However, the reference codec of the standard, the joint model (JM) contains quite a few algorithms which are too complex to be used for the resource-constraint embedded environment. This paper introduces very low-complexity H.264 encoding algorithm which is applicable for the embedded environment. The proposed algorithm was realized by restricting some coding tools on the basis that it should not cause too severe degradation of RD-performance and adding a few early termination and bypass conditions during the motion estimation and mode decision process. In case of encoding of 7.5fps QCIF sequence with 64kbpswith the proposed algorithm, the encoder yields worse PSNRs by 0.4 dB than the standard JM, but requires only $15\%$ of computational complexity and lowers the required memory and power consumption drastically. By porting the proposed H.264 codec into the PDA with Intel PXA255 Processor, we verified the feasibility of the H.264 based MMS(Multimedia Messaging Service) on PDA.

Development of Neural Network Model for Estimation of Undrained Shear Strength of Korean Soft Soil Based on UU Triaxial Test and Piezocone Test Results (비압밀-비배수(UU) 삼축실험과 피에조콘 실험결과를 이용한 국내 연약지반의 비배수전단강도 추정 인공신경망 모델 개발)

  • Kim Young-Sang
    • Journal of the Korean Geotechnical Society
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    • v.21 no.8
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    • pp.73-84
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    • 2005
  • A three layered neural network model was developed using back propagation algorithm to estimate the UU undrained shear strength of Korean soft soil based on the database of actual undrained shear strengths and piezocone measurements compiled from 8 sites over the Korea. The developed model was validated by comparing model predictions with measured values about new piezocone data, which were not previously employed during development of model. Performance of the neural network model was also compared with conventional empirical methods. It was found that the number of neuron in hidden layer is different for the different combination of transfer functions of neural network models. However, all piezocone neural network models are successful in inferring a complex relationship between piezocone measurements and the undrained shear strength of Korean soft soils, which give relatively high coefficients of determination ranging from 0.69 to 0.72. Since neural network model has been generalized by self-learning from database of piezocone measurements and undrained shear strength over the various sites, the developed neural network models give more precise and generally reliable undrained shear strengths than empirical approaches which still need site specific calibration.

Hybrid Asymmetric Watermarking using Correlation and Critical Criteria (상관도와 임계치 방식을 이용한 다중검출 비대칭 워터마킹)

  • Li De;Kim Jong-Weon;Choi Jong-Uk
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.7C
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    • pp.726-734
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    • 2005
  • Traditional watermarking technologies are symmetric method which embedding and detection keys are the same. Although the symmetric watermarking method is easy to detect the watermark, this method has weakness against to malicious attacks remove or modify the watermark information when the symmetric key is disclosure. Recently, the asymmetric watermarking method that has different keys to embed and detect is watched by several researchers as a next generation watermarking technology. In this paper, hybrid asymmetric watermarking algorithm is proposed. This algorithm is composed of correlation detection method and critical criteria method. Each method can be individually used to detect watermark from a watermarked content. Hybrid asymmetric detection is complement between two methods, and more feasible than when each method is used respectively, Private key and public key are generated by secure linear transformation and specific matrix. As a result, we have proved the proposed algorithm is secured than symmetric watermarking algorithms. This algorithm can expand to multi bits embedding watermark system and is robust to JPEG and JPEG2000 compression.

Fast Intra-Mode Decision for H.264/AVC using Inverse Tree-Structure (H.264/AVC 표준에서 역트리 구조를 이용하여 고속으로 화면내 모드를 결정하는 방법)

  • Ko, Hyun-Suk;Yoo, Ki-Won;Seo, Jung-Dong;Sohn, Kwang-Hoon
    • Journal of Broadcast Engineering
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    • v.13 no.3
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    • pp.310-318
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    • 2008
  • The H.264/AVC standard achieves higher coding efficiency than previous video coding standards with the rate-distortion optimization (RDO) technique which selects the best coding mode and reference frame for each macroblock. As a result, the complexity of the encoder have been significantly increased. In this paper, a fast intra-mode decision algorithm is proposed to reduce the computational load of intra-mode search, which is based on the inverse tree-structure edge prediction algorithm. First, we obtained the dominant edge for each $4{\times}4$ block from local edge information, then the RDO process is only performed by the mode which corresponds to dominant edge direction. Then, for the $8{\times}8$ (or $16{\times}16$) block stage, the dominant edge is calculated from its four $4{\times}4$ (or $16{\times}16$) blocks' dominant edges without additional calculation and the RDO process is also performed by the mode which is related to dominant edge direction. Experimental results show that proposed scheme can significantly improve the speed of the intra prediction with a negligible loss in the peak signal to noise ratio (PSNR) and a little increase of bits.

Photoelastic Stress Analysis for a Rhombus Plate under Compressive Load Using Image Processing Technique (압축하중을 받는 마름모 판에 대한 영상처리기법을 이용한 광탄성 응력 해석)

  • Liu, Guan Yong;Kim, Myung Soo;Baek, Tae Hyun
    • Journal of the Korean Society for Nondestructive Testing
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    • v.34 no.2
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    • pp.148-154
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    • 2014
  • Photoelasticity is a useful technique for obtaining the differences and directions of principal stresses in a model. In conventional photoelasticity, the photoelastic parameters are measured manually point by point. Identifying and measuring photoelastic data is time-consuming and requires skill. The fringe phase shifting method was recently developed and has been found to be convenient for measuring and analyzing fringe data in photo-mechanics. This paper presents an experimental study on the stress distribution along a horizontal line that passes the central point of a rhombus plate made of Photoflex (i.e., type of urethane rubber). The isoclinic fringe and/or principal stress direction is constant on this horizontal line, so a four-bucket phase shifting method can be applied. The method requires four photoelastic fringes that are obtained from a circular polariscope by rotating the analyzer at $0^{\circ}C$, $45^{\circ}C$, $90^{\circ}C$ and $135^{\circ}C$. Experimental measurements using the method were quantitatively compared with the results from FEM analysis; the results from the two methods showed comparable agreement.

A Design of Pipelined-parallel CABAC Decoder Adaptive to HEVC Syntax Elements (HEVC 구문요소에 적응적인 파이프라인-병렬 CABAC 복호화기 설계)

  • Bae, Bong-Hee;Kong, Jin-Hyeung
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.5
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    • pp.155-164
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    • 2015
  • This paper describes a design and implementation of CABAC decoder, which would handle HEVC syntax elements in adaptively pipelined-parallel computation manner. Even though CABAC offers the high compression rate, it is limited in decoding performance due to context-based sequential computation, and strong data dependency between context models, as well as decoding procedure bin by bin. In order to enhance the decoding computation of HEVC CABAC, the flag-type syntax elements are adaptively pipelined by precomputing consecutive flag-type ones; and multi-bin syntax elements are decoded by processing bins in parallel up to three. Further, in order to accelerate Binary Arithmetic Decoder by reducing the critical path delay, the update and renormalization of context modeling are precomputed parallel for the cases of LPS as well as MPS, and then the context modeling renewal is selected by the precedent decoding result. It is simulated that the new HEVC CABAC architecture could achieve the max. performance of 1.01 bins/cycle, which is two times faster with respect to the conventional approach. In ASIC design with 65nm library, the CABAC architecture would handle 224 Mbins/sec, which could decode QFHD HEVC video data in real time.