• Title/Summary/Keyword: Image Codec

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Efficient Digital Video Recording / Searching / Internet-Streaming Techniques for Multi-Channel DVR Systems (다채널 DVR 시스템을 위한 효율적인 디지털 비디오 저장 탐색 및 인터넷 전송 기술)

  • Shin, Tae-Hyun;Lee, Jae-Sung;Shin, Hyun-Chul
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.959-962
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    • 2005
  • Efficient video data storage and search techniques are essential for DVR-based security systems. We have designed appropriate data structures and search techniques for efficient image storage and search, in this study. The date and time can be saved and searched as a folder form. The overall system is designed for MPEG4 CODEC. It can handle variable sizes of frames (100bytes $^{\sim}$ 6Kbytes) produced by MPEG4 CODEC without errors. We also have developed image transmission techniques through inter-net networking.

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A Sequencial Adaptive Kalman Filtering for Video Codec Image Enhancement (Video Codec 화질 개선을 위한 순차적 적응형 칼만 필터링 연구)

  • 백원진;이종수;김수원;박진우
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.15 no.12
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    • pp.1031-1043
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    • 1990
  • A sequential recursive Kalman filtering algorithm, using causal image model, which is designed to operate in real time in the scanning mode is developed to enhance quality of 64Kbps videocodec images via function of suppression of various noises and optimum restoration. In order to improve its performance, adapted an averaging of pixel values between processing lines and adaptive filtering strategy based on the local spatial variance. Effecttiveness of the Kalman filtering algorithm proposed has been proved in the processed test kalman filtering algorithm proposed has been proved in the processed test images and the NMSE, LOGMSE measured, therefore, it may proposes possibility of the usage in videocodec for pre- and post- processing.

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A Design of Efficient Scan Converter for Image Compression CODEC (영상압축코덱을 위한 효율적인 스캔변환기 설계)

  • Lee, Gunjoong;Ryoo, Kwangki
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.2
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    • pp.386-392
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    • 2015
  • Data in a image compression codec are processed with a specific regular block size. The processing order of block sized data is changed in specific function blocks and the data is packed in memory and read by a new sequence. To maintain a regular throughput rate, double buffering is normally used that interleaving two block sized memory to do concurrent read and write operations. Single buffering using only one block sized memory can be adopted to the simple data reordering, but when a complicate reordering occurs, irregular address changes prohibit from implementing adequate address generating for single buffering. This paper shows that there is a predictable and recurring regularity of changing address access orders within a finite updating counts and suggests an effective method to implement. The data reordering function using suggested idea is designed with HDL and implemented with TSMC 0.18 CMOS process library. In various scan blocks, it shows more than 40% size reduction compared with a conventional method.

A research for design of high efficiency DVR system using H.264 codec (H.264 코덱을 사용한 고성능 DVR 시스템 개발에 관한 연구)

  • Lee, Il-Joo;Lim, Sung-Jun;Chae, Hyun-Suk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.1
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    • pp.110-116
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    • 2009
  • It is very important for a DVR system to compress mass video data because they should be able to store#playback of video data. There are several high efficient DVR products using ordinary MPEG-4 compression fur data compression. But most of them support only CIF(D1/4) image, which means degraded image quality in comparison with input image source. In this paper, M-JPEG and H.264 Codec are realized using DSP. To multiple channels system M-JPEG is used for data transmission through network, and Data compression rate is improved as about 4 times as ordinary MPEG-4 compression by supporting Baseline Profile of H.264. As a result, high resolution with the width 720 pixels and the height 480 pixels can be supported.

MRBR-based JPEG2000 Codec for Stereoscopic Image Compression of 3-Dimensional Digital Cinema (3차원 디지털 시네마의 스테레오 영상 압축을 위한 MRBR기반의 JPEG2000 코덱)

  • Seo, Young-Ho;Sin, Wan-Soo;Choi, Hyun-Jun;Yoo, Ji-Sang;Kim, Dong-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.12
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    • pp.2146-2152
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    • 2008
  • In In this paper, we proposed a new JPEG2000 codec using multiresolution-based rendering (MRBR) technique for video compression of 3-dimensional digital cinema. We introduced discrete wavelet transform (DWT) for stereoscopic image and stereo matching technique in the wavelet domain. The disparity was extracted using stereo matching and transmitted with the reference (left) image. Since the generated right image was degraded by the occlusion lesion, the residual image which is generated from difference between the original right image and the generated one was transmitted at the same tine. The disparity data was extracted using the dynamic programming method in the disparity domain. There is high correlation between the higher and lower subbands. Therefore we decreased the calculation amount and enhanced accuracy by restricting the search window and applying the disparity information generated from higher subband.

Multi-view Synthesis Algorithm for the Better Efficiency of Codec (부복호화기 효율을 고려한 다시점 영상 합성 기법)

  • Choi, In-kyu;Cheong, Won-sik;Lee, Gwangsoon;Yoo, Jisang
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.2
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    • pp.375-384
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    • 2016
  • In this paper, when stereo image, satellite view and corresponding depth maps were used as the input data, we propose a new method that convert these data to data format suitable for compressing, and then by using these format, intermediate view is synthesized. In the transmitter depth maps are merged to a global depth map and satellite view are converted to residual image corresponding hole region as out of frame area and occlusion region. And these images subsampled to reduce a mount of data and stereo image of main view are encoded by HEVC codec and transmitted. In the receiver intermediate views between stereo image and between stereo image and bit-rate are synthesized using decoded global depth map, residual images and stereo image. Through experiments, we confirm good quality of intermediate views synthesized by proposed format subjectively and objectively in comparison to intermediate views synthesized by MVD format versus total bit-rate.

Hybrid No-Reference Video Quality Assessment Focusing on Codec Effects

  • Liu, Xingang;Chen, Min;Wan, Tang;Yu, Chen
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.3
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    • pp.592-606
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    • 2011
  • Currently, the development of multimedia communication has progressed so rapidly that the video program service has become a requirement for ordinary customers. The quality of experience (QoE) for the visual signal is of the fundamental importance for numerous image and video processing applications, where the goal of video quality assessment (VQA) is to automatically measure the quality of the visual signal in agreement with the human judgment of the video quality. Considering the codec effect to the video quality, in this paper an efficient non-reference (NR) VQA algorithm is proposed which estimates the video quality (VQ) only by utilizing the distorted video signal at the destination. The VQA feature vectors (FVs) which have high relationships with the subjective quality of the distorted video are investigated, and a hybrid NR VQA (HNRVQA) function is established by considering the multiple FVs. The simulation results, testing on the SDTV programming provided by VCEG Phase I, show that the proposed algorithm can represent the VQ accurately, and it can be used to replace the subjective VQA to measure the quality of the video signal automatically at the destinations.

A VLSI Design of Discrete Wavelet Transform and Scalar Quantization for JPEG2000 CODEC (JPEG2000 CODEC을 위한 DWT및 양자화기 VLSI 설계)

  • 이경민;김영민
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.40 no.1
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    • pp.45-51
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    • 2003
  • JPEG200, a new international standard for still image compression based on wavelet and bit-plane coding techniques, is developed. In this paper, we design the DWT(Discrete Wavelet Transform) and quantizer for JPEG2000 CODEC. DWT handles both lossy and lossless compression using the same transform-based framework: The Daubechies 9/7 and 5/3 transforms, and quantizer is implemented as SQ(Scalar Quantization). The architecture of the proposed DWT and SQ are synthesized and verified using Xilinx FPGA technology. It operates up to 30MHz, and executes algorithms of wavelet transform and quantization for VGA 10 frame per second.

A Study on the Interframe Image Coding Using Motion Compensated and Classified Vector Quantizer (Ⅱ : Hardware Implementation) (이동 보상과 분류 벡터 양자화기를 이용한 영상 부호화에 관한 연구 (Ⅱ: 하드웨어 실현))

  • Jeon, Joong-Nam;Shin, Tae-Min;Choi, Sung-Nam;Park, Kyu-Tae
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.27 no.3
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    • pp.21-30
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    • 1990
  • This paper describes a hardware implementation of the interframe monochrome video CODEC using a MC-CVQ(Motion Compensated and Classified Vector Quantization) algorithm. The specifications of this CODEC are (1) the resolution of image is $128{\times}128$ pixels, and (2) the transmission rates are about 10frames/sec at the 64Kbps channel. In order to design the CODEC under these conditions, it is implemented by a multiprocessor system composed of MC unit, CVQ nuit and decoder unit, which are controlled by microprogramming technique. And the 3~stage pipelined ALU(Arithmetic and Logic Unit) is adopted to calculate the minimum error distance in the MC unit and CVQ nuit. The realized system shows that the transmission rates are 6-15 frames/sec according to the relative motion of the video signal.

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Multi-view Video Codec for 3DTV (3DTV를 위한 다시점 동영상 부호화 기법)

  • Bae Jin-Woo;Song Hyok;Yoo Ji-Sang
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.3A
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    • pp.337-344
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    • 2006
  • In this paper, we propose a multi-view video codec for 3DTV system. The proposed algorithm is not only to reduce the temporal and spatial redundancy but also to reduce the redundancy among each view. With these results, we can improve the coding efficiency for multi-view video sequences. In order to reduce the redundancy of each view more efficiently, we define the assembled image(AI) that is generated by the global disparity compensation of each view. In addition, the proposed algorithm is based on MPEG-2 structure so that we can easily implement 3DTV system without changing the conventional 2D digital TV system. Experimental results show that the proposed algorithm performs very well. It also performs better than MPEG-2 simulcast coding method. The newly proposed codec also supports the view scalability, accurate temporal synchronization among multiple views and random access capability in view dimension.