• Title/Summary/Keyword: Run-length code

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Binary Image Watermarking for Preserving Feature Regions (특징영역을 보존한 이진영상의 워터마킹)

  • 이정환
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.6 no.4
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    • pp.624-631
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    • 2002
  • In this paper, an effective digital watermarking method for copyright protection of binary image data is proposed. First a binary image is grouped into feature regions which has geometrical features and general one. The watermark for authentication is embedded in general regions in order to preserve geometrical features regions. We have used run-length code and special runs for grouping feature regions and general one. For invisibility of watermark, we have embedded the watermark considering transition sensitivity of each pixel in general regions. The proposed method is applied some binary image such as character, signature, seal, and fingerprint image to evaluate performance. By the experimental results, the proposed method preserve feature regions of original image and have higher invisibility of watermarks.

Binary Image Watermarking Based on Grouping Feature Regions (특수런을 이용한 특징영역 분리에 의한 이진영상 워터마킹)

  • 이정환;박세현;노석호
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2002.05a
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    • pp.177-180
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    • 2002
  • In this paper, an effective digital watermarking method for copyright protection of binary image data is proposed. First, a binary image is grouped into feature regions which have geometrical features and general one. The watermark for authentication is embedded in general regions in order to preserve geometrical features regions. We have used run-length code and special runs for grouping feature regions and general one. For invisibility of watermark, we have embedded the watermark considering transition sensitivity of each pixel in general regions. The proposed method is applied to some binary image such as character, signature, seal, and fingerprint image to evaluate performance. By the experimental results, the proposed method preserve feature regions of original image and have higher invisibility of watermarks.

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Feature Extraction of Shape of Image Objects in Content-based Image Retrieval (내용기반으로한 이미지 검색에서 이미지 객체들의 외형특징추출)

  • Cho, June-Suh
    • The KIPS Transactions:PartB
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    • v.10B no.7
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    • pp.823-828
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    • 2003
  • The main objective of this paper is to provide a methodology of feature extraction using shape of image objects for content-based image retrieval. The shape of most real-life objects is irregular, and hence there is no universal approach to quantify the shape of an arbitrary object. In particular. electronic catalogs contain many image objects for their products. In this paper, we perform feature extraction based on individual objects in images rather than on the whole image itself, since our method uses a shape-based approach of objects using RLC lines within an image. Experiments show that shape parameters distinctly represented image objects and provided better classification and discrimination among image objects in an image database compared to Texture.

Distributed Video Coding Based on Selective Block Encoding Using Feedback of Motion Information (움직임 정보의 피드백을 갖는 선택적 블록 부호화에 기초한 분산 비디오 부호화 기법)

  • Kim, Jin-Soo;Kim, Jae-Gon;Seo, Kwang-Deok;Lee, Myeong-Jin
    • Journal of Broadcast Engineering
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    • v.15 no.5
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    • pp.642-652
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    • 2010
  • Recently, DVC (Distributed Video Coding) techniques are drawing a lot of interests as one of the future research works to achieve low complexity encoding in various applications. But, due to the limited computational complexity, the performances of DVC algorithms are inferior to those of conventional international standard video coders, which use zig-zag scan, run length code, entropy code and skipped macroblock. In this paper, in order to overcome the performance limit of the DVC system, the distortion for every block is estimated when side information is found at the decoder and then we propose a new selective block encoding scheme which provides the encoder side with the motion information for the highly distorted blocks and then allows the sender to encode the motion compensated frame difference signal. Through computer simulations, it is shown that the coding efficiency of the proposed scheme reaches almost that of the conventional inter-frame coding scheme.

A Dual Noise-Predictive Partial Response Decision-Feedback Equalizer for Perpendicular Magnetic Recording Channels (수직 자기기록 채널을 위한 쌍 잡음 예측 부분 응답 결정 궤환 등화기)

  • 우중재;조한규;이영일;홍대식
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.9C
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    • pp.891-897
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    • 2003
  • Partial response maxim likelihood (PRML) is a powerful and indispensable detection scheme for perpendicular magnetic recording channels. The performance of PRML can be improved by incorporating a noise prediction scheme into branch metric computations of Viterbi algorithm (VA). However, the systems constructed by VA have shortcomings in the form of high complexity and cost. In this connection, a new simple detection scheme is proposed by exploiting the minimum run-length parameter d=1 of RLL code. The proposed detection scheme have a slicer instead of Viterbi detector and a noise predictor as a feedback filter. Therefore, to improve BER performance, the proposed detection scheme is extended to dual detection scheme for improving the BER performance. Simulation results show that the proposed scheme has a comparable performance to noise-predictive maximum likelihood (NPML) detector with less complexity when the partial response (PR) target is (1,2,1).

Efficient Blind Estimation of Block Interleaver Parameters (효율적인 블록 인터리버 파라미터 블라인드 추정 기법)

  • Jeong, Jin-Woo;Choi, Sung-Hwan;Yoon, Dong-Weon;Park, Cheol-Sun;Yoon, Sang-Bom
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.5C
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    • pp.384-392
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    • 2012
  • Recently, much research on blind estimation of the interleaver parameters has been performed by using Gauss-Jordan elimination to find the linearity of the block channel code. When using Gauss-Jordan elimination, the input data to be calculated needs to run as long as the square multiple of the number of the interleaver period. Thus, it has a limit in estimating the interleaver parameters with insufficient input data. In this paper, we introduce and analyze an estimation algorithm which can estimate interleaver parameters by using only 15 percent of the input data length required in the above algorithm. The shorter length of input data to be calculated makes it possible to estimate the interleaver parameters even when limited data is received. In addition, a 80 percent reduction in the number of the interleaver period candidates increases the efficiency of analysis. It is also feasible to estimate both the type and size of the interleaver and the type of channel coding.

An Efficient Medical Image Compression Considering Brain CT Images with Bilateral Symmetry (뇌 CT 영상의 대칭성을 고려한 관심영역 중심의 효율적인 의료영상 압축)

  • Jung, Jae-Sung;Lee, Chang-Hun
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.5
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    • pp.39-54
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    • 2012
  • Picture Archiving and Communication System (PACS) has been planted as one of the key infrastructures with an overall improvement in standards of medical informationization and the stream of digital hospitalization in recent days. The kind and data of digital medical imagery are also increasing rapidly in volume. This trend emphasizes the medical image compression for storing large-scale medical image data. Digital Imaging and Communications in Medicine (DICOM), de facto standard in digital medical imagery, specifies Run Length Encode (RLE), which is the typical lossless data compressing technique, for the medical image compression. However, the RLE is not appropriate approach for medical image data with bilateral symmetry of the human organism. we suggest two preprocessing algorithms that detect interested area, the minimum bounding rectangle, in a medical image to enhance data compression efficiency and that re-code image pixel values to reduce data size according to the symmetry characteristics in the interested area, and also presents an improved image compression technique for brain CT imagery with high bilateral symmetry. As the result of experiment, the suggested approach shows higher data compression ratio than the RLE compression in the DICOM standard without detecting interested area in images.

The Cooperative Parallel X-Match Data Compression Algorithm (협동 병렬 X-Match 데이타 압축 알고리즘)

  • 윤상균
    • Journal of KIISE:Computer Systems and Theory
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    • v.30 no.10
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    • pp.586-594
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    • 2003
  • X-Match algorithm is a lossless compression algorithm suitable for hardware implementation owing to its simplicity. It can compress 32 bits per clock cycle and is suitable for real time compression. However, as the bus width increases 64-bit, the compression unit also need to increase. This paper proposes the cooperative parallel X-Match (X-MatchCP) algorithm, which improves the compression speed by performing the two X-Match algorithms in parallel. It searches the all dictionary for two words, combines the compression codes of two words generated by parallel X-Match compression and outputs the combined code while the previous parallel X-Match algorithm searches an individual dictionary. The compression ratio in X-MatchCP is almost the same as in X-Match. X-MatchCP algorithm is described and simulated by Verilog hardware description language.

Real-Time DSP Implementation of IMT-2000 Speech Coding Algorithm (IMT-2000 음성부호화 알고리즘의 실시간 DSP 구현)

  • Seo, Jeong-Uk;Gwon, Hong-Seok;Park, Man-Ho;Bae, Geon-Seong
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.38 no.3
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    • pp.304-315
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    • 2001
  • In this paper, we peformed the real-time implementation of AMR(Adaptive Multi-Rate) speech coding algorithm which is adopted for IMT-2000 service using TMS320C6201, i.e., a Texas Instrument´s fixed-point DSP. With the ANSI C source code released from ETSI, optimization is performed to make it run in real-time with memory as small as possible using the C compiler and assembly language. Implemented AMR speech codec has the size of 32.06 kWords program memory, 9.75 kWords data RAM memory, and 19.89 kWords data ROM memory. And, The time required for processing one frame of 20 ms length speech data is about 4.38 ms, and it is short enough for real-time operation. It is verified that the decoded result of the implemented speech codec on the DSP is identical with the PC simulation result using ANSI C code for test sequences. Also, actual sound input/output test using microphone and speaker demonstrates its proper real-time operation without distortions or delays.

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