• Title/Summary/Keyword: Block size decision

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Size-Independent Caption Extraction for Korean Captions with Edge Connected Components

  • Jung, Je-Hee;Kim, Jaekwang;Lee, Jee-Hyong
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.12 no.4
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    • pp.308-318
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    • 2012
  • Captions include information which relates to the images. In order to obtain the information in the captions, text extraction methods from images have been developed. However, most existing methods can be applied to captions with a fixed height or stroke width using fixed pixel-size or block-size operators which are derived from morphological supposition. We propose an edge connected components based method that can extract Korean captions that are composed of various sizes and fonts. We analyze the properties of edge connected components embedding captions and build a decision tree which discriminates edge connected components which include captions from ones which do not. The images for the experiment are collected from broadcast programs such as documentaries and news programs which include captions with various heights and fonts. We evaluate our proposed method by comparing the performance of the latent caption area extraction. The experiment shows that the proposed method can efficiently extract various sizes of Korean captions.

Fast Intra-Prediction Mode Decision Algorithm using Predetermined Prediction Block Size in H.264/AVC (H.264/AVC의 인트라 예측에서 예측 블록 크기 정보를 이용한 빠른 예측 모드 결정 기법)

  • Kim, Young-ju
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.10a
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    • pp.211-214
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    • 2009
  • H.264/AVC의 인트라 예측에서 미리 현재 블록 내의 정보 및 이전 블록의 예측 모드 정보 등을 이용하여 현재 블록의 예측 부호화 블록 크기가 결정되었을 경우, 예측된 블록 크기에 적합한 예측 모드 결정이 요구된다. 이에 사전에 결정된 예측 블록 크기 정보와 주변 블록과의 화소 변화량을 계산하여 예측 모드를 결정하는 기법을 제안하고 성능을 평가한다.

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A Block Replacement Scheme using Analytic Hierarchy Process in Hybrid HDD (하이브리드 하드디스크에서 AHP를 적용한 블록 교체 기법)

  • Kim, Jeong-Won
    • Journal of Korea Society of Industrial Information Systems
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    • v.20 no.5
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    • pp.45-52
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    • 2015
  • The read performance of hybrid hard disk is better than the legacy hard disk and power consumption is also considerably low. As blocks with enough localities may be located in the non-volatile cache whose size is generally limited, an effective block replacement scheme is required. As this replacement is inevitably affected by various parameters, we define this issue as a kind of multiple criteria decision model. To solve this problem, this paper suggests a new block replacement algorithm based on the analytic hierarchy process. Through simulation for our model, we confirmed that the proposed model could be used as a replacement algorithm of the hybrid hard disk as it may improve boot time as well as response time of general applications.

A Study on Efficient Coding Mode Decision for H.264/AVC (H.264/AVC의 효율적인 부호화 모드 결정에 관한 연구)

  • Hur, Tae-Won
    • Journal of the Korea Computer Industry Society
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    • v.6 no.5
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    • pp.801-812
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    • 2005
  • H.264/AVC is the international video coding standard which has significant improvements of coding efficiency. ITU-T(International Telecommunication Union-Telecommunication standardization sector) and MPEG(Moving Picture Experts Group) adopts various complex coding tool such as variable block size motion, multiple reference frames, quarter-pel motion estimation/compensation (ME/MC) and rate-distortion(RD) optimization, etc. H.264 reference model employs complex mode decision technique based on RD optimization which requires high computational complexity. In this paper, we propose an efficient coding mode decision based on the cost distribution of RD in the macroblock coding mode sequence. Simulation results show that the proposed method reduces encoding time by 34% on average and save the number of computing RD cost by 82%.

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The Algorithm of Angular Mode Selection for High Performance HEVC Intra Prediction (고성능 HEVC 화면내 예측을 위한 Angular 모드 선택 알고리즘)

  • Park, Seungyong;Ryoo, Kwangki
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.10a
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    • pp.969-972
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    • 2016
  • In this paper, we propose an algorithm of angular mode selection for high-performance HEVC intra prediction. HEVC intra prediction is used to remove the spatial redundancy. Intra prediction has a total of 35 modes and block size of $64{\times}64$ to $4{\times}4$. Intra prediction has a high amount of calculation and operational time due to performing all 35 modes for each block size for the best cost. The angular mode algorithm proposed has a simple difference between pixels of the original image and the selected angular mode. A decision is made to select one angular mode plus planar mode and DC mode to perform the intra prediction and determine the mode with the best cost. In effect, only three modes are executed compared to the traditional 35 modes. Performance evaluation index used are BD-PSNR and BD-Bitrate. For the proposed algorithm, BD-PSNR results averagely increased by 0.035 and BD-Bitrate decreased by 0.623 relative to the HM-16.9 intra prediction. In addition, the encoding time is decreased by about 6.905%.

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Enhanced Prediction for Low Complexity Near-lossless Compression (낮은 복잡도의 준무손실 압축을 위한 향상된 예측 기법)

  • Son, Ji Deok;Song, Byung Cheol
    • Journal of Broadcast Engineering
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    • v.19 no.2
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    • pp.227-239
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    • 2014
  • This paper proposes an enhance prediction for conventional near-lossless coder to effectively lower external memory bandwidth in image processing SoC. First, we utilize an already reconstructed green component as a base of predictor of the other color component because high correlation between RGB color components usually exists. Next, we can improve prediction performance by applying variable block size prediction. Lastly, we use minimum internal memory and improve a temporal prediction performance by using a template dictionary that is sampled in previous frame. Experimental results show that the proposed algorithm shows better performance than the previous works. Natural images have approximately 30% improvement in coding efficiency and CG images have 60% improvement on average.

A Study on Fast Macroblock Partition Decision Method at H264 (H.264에서 고속 매크로 블록 분할 결정 방법에 관한 연구)

  • Song, Dae-Geon
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.6
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    • pp.99-105
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    • 2014
  • The performance improvement in MPEG-4 AVC is provided at the expense for higher computational complexity. Most of the complexity is caused by Inter prediction. To improve coding efficiency, some functions are added in H.264/MPEG-4 AVC, such as variable block size motion compensation, multi reference frame and quarter-pel motion compensation. A fast macroblock partition decision method is proposed in this paper. The macroblock size is efficiently determined by using the pixel value difference between encoding and the referred macroblock.

A Hardware Design of Effective Intra Prediction Angular Mode Decision for HEVC Encoder (HEVC 부호기를 위한 효율적인 화면내 예측 Angular 모드 결정 하드웨어 설계)

  • Park, Seungyong;Choi, Juyong;Ryoo, Kwangki
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.4
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    • pp.767-773
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    • 2017
  • In this paper, we propose a design of Intra prediction angular mode decision for HEVC encoder. Intra prediction coding of HEVC is a method for predicting a current block by referring to samples reconstructed around a current block. Intra prediction supports a total of 35 modes with 1 DC mode, 1 Planar mode, and 33 Angular modes. Intra prediction coding of HEVC works by performing all 35 modes for efficient encoding. However, in order to process all of the 35 modes, the computational complexity and operational time required are high. Therefore, this paper proposes comparing the difference in the value of the original pixel, using an algorithm that determines angular mode efficiently. This new algorithm reduces the Hardware size. The hardware which is proposed was designed using Verilog HDL and was implemented in 65nm technology. Its gate count is 14.9K and operating speed is 2GHz.

Enhanced Mode Estimation Method for Intra/Inter Prediction in H.264/AVC (H.264/AVC에서 향상된 인트라/인터 예측을 위한 모드 추정 방법)

  • Park, Kyung-Seok;Kim, Min-Jun;Jun, Jae-Hyun;Ryu, Sang-Ryul;Kim, Snng-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.4
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    • pp.1830-1838
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    • 2012
  • The intra prediction and the motion estimation of inter prediction occupy 70 ~ 80% of whole compression time in H.264/AVC. Compression efficiency has been higher, but complexity has increased and coding time has also increased much more. This paper proposes a block size decision method of the intra prediction and mode decision method which minimize the loss of video quality during the encoding and shorten the time spent. This paper, in addition, proposes an algorithm which determines the method of adaptive block mode for motion estimation of inter prediction. We investigated PSNR and the intra prediction and inter prediction of time-consuming calculations in order to measure video quality degradation and complexity through experiments. Consequently, when you use all three methods, these methods showed that average coding time is shortened as about 500 to 600ms in every frame in the case of all experimented videos, keeping video quality nearly similar, compared with existing methods of H.264.

Mode Skip Method of Multiple Reference Frames in H.264 (H.264에서의 다중 참조 영상 간 모드 생략 기법)

  • Kwon, Jae-Hyun;Kang, Min-Jung;Ryu, Chul
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.285-286
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    • 2006
  • H.264 provide good coding efficiency compared with existing video coding standards as H.263, MPEG-4, etc. However, H.264 require the increase of encoder complexity. In this paper, fast mode decision algorithm by skipping variable block size motion estimation and spatial-predictive coding, which occupies most encoder complexity, is proposed. Experimental results show that the proposed approach can save encoding time to 55% compared with the H.264 standard.

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