• Title/Summary/Keyword: Adaptive Threshold Method

Search Result 308, Processing Time 0.026 seconds

A Study on a effective Information Compressor Algorithm for the variable environment variation using the Kalman Filter

  • Choi, Jae-Yun
    • Journal of the Korea Society of Computer and Information
    • /
    • v.23 no.4
    • /
    • pp.65-70
    • /
    • 2018
  • This paper describes a effective information compressor algorithm for the fourth industrial technology. One of the difficult problems for outdoor is to obtain effective updating process of background images. Because input images generally contain the shadows of buildings, trees, moving clouds and other objects, they are changed by lapse of time and variation of illumination. They provide the lowering of performance for surveillance system under outdoor. In this paper, a effective information algorithm for variable environment variable under outdoor is proposed, which apply the Kalman Estimation Modeling and adaptive threshold on pixel level to separate foreground and background images from current input image. In results, the better SNR of about 3dB~5dB and about 10%~25% noise distribution rate in the proposed method. Furthermore, it was showed that the moving objects can be detected on various shadows under outdoor and better result Information.

Patient Adaptive Pattern Matching Method for Premature Ventricular Contraction(PVC) Classification (조기심실수축(PVC) 분류를 위한 환자 적응형 패턴 매칭 기법)

  • Cho, Ik-Sung;Kwon, Hyeog-Soong
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.16 no.9
    • /
    • pp.2021-2030
    • /
    • 2012
  • Premature ventricular contraction(PVC) is the most common disease among arrhythmia and it may cause serious situations such as ventricular fibrillation and ventricular tachycardia. Particularly, in the healthcare system that must continuously monitor patient's situation, it is necessary to process ECG (Electrocardiography) signal in realtime. In other words, the design of algorithm that exactly detects R wave using minimal computation and classifies PVC by analyzing the persons's physical condition and/or environment is needed. Thus, the patient adaptive pattern matching algorithm for the classification of PVC is presented in this paper. For this purpose, we detected R wave through the preprocessing method, adaptive threshold and window. Also, we applied pattern matching method to classify each patient's normal cardiac behavior through the Hash function. The performance of R wave detection and abnormal beat classification is evaluated by using MIT-BIH arrhythmia database. The achieved scores indicate the average of 99.33% in R wave detection and the rate of 0.32% in abnormal beat classification error.

Frequency Adaptive Hard-Decision Quantization for Video Coding (영상 부호화를 위한 주파수 적응형 경판정 양자화)

  • Xu, Motong;Jeon, Byeungwoo
    • Proceedings of the Korean Society of Broadcast Engineers Conference
    • /
    • 2019.11a
    • /
    • pp.194-195
    • /
    • 2019
  • In this paper, we propose a frequency location adaptive hard-decision quantization (HDQ) scheme for video coding. A threshold for zero quantized level is adaptively applied to unquantized transform coefficients based on its frequency location in the transform domain. The proposed method achieves an average of 1.13%, 1.57%, and 1.53% of bit-rate reduction in BDBR sense compared to the conventional HDQ scheme respectively in Y, Cb, and Cr under the all intra encoding configuration.

  • PDF

Locally Adaptive Bi-level Image Segmentation Technique (국부 적응 2 진 화상 영역화 기법)

  • Jung, Gyoo-Sung;Park, Rae-Hong
    • Proceedings of the KIEE Conference
    • /
    • 1987.07b
    • /
    • pp.1367-1370
    • /
    • 1987
  • This paper describes a new automatic bi-level image segmentation algorithm which determines local thresholds by applying a locally adaptive edge detection technique to a variable threshold selection method. Computer simulations show that the performance of the proposed algorithm is more robust than those of automatic global thresholding methods.

  • PDF

Adaptive Multi-threshold Based Mura Detection on A LCD Panel (적응적 임계화법에 기반한 LCD 얼룩 검사)

  • 류재승;곽동민;박길흠
    • Proceedings of the IEEK Conference
    • /
    • 2003.11a
    • /
    • pp.347-350
    • /
    • 2003
  • In this paper, a new automated defects detection method for a TFT-LCD panel is presented. An input image is preprocessed to lessen small abnormal noises and non-uniformity of the image. The adaptive multi-thresholds are used to detect Muras, which are the major defects occurred on TFT-LCD panels. Those are determined adaptively depending on the brightness and the brightness distribution of a local block. For the synthetic images and real Mura images, the proposed algorithm can effectively detect Muras in a reasonable time.

  • PDF

Single Logarithmic Amplification and Deep Learning-based Fixed-threshold On-off Keying Detection for Free-space Optical Communication

  • Qian-Wen Jing;Yan-Qing Hong
    • Current Optics and Photonics
    • /
    • v.8 no.3
    • /
    • pp.239-245
    • /
    • 2024
  • This paper proposes single logarithmic amplification (single-LA) and deep learning (DL)-based fixed-threshold on-off keying (OOK) detection for free-space optical (FSO) communication. Multilevel LAs (MLAs) can be used to mitigate intensity fluctuations in the received OOK signal by their nonlinear gain characteristics; however, it is ineffective in the case of high scintillation, owing to degradation of the OOK signal's extinction ratio. Therefore, a DL technique is applied to realize effective scintillation compensation in single-LA applications. Fully connected (FC) networks and fully connected neural networks (FCNN), which have nonlinear modeling characteristics, are deployed in this work. The performance of the proposed method is evaluated through simulations under various scintillation effects. Simulation results show that the proposed method outperforms the conventional adaptive-threshold-decision, single-LA-based, MLA-based, FC-based, and FCNN-based OOK detection techniques.

Voice Activity Detection based on Adaptive Band-Partitioning using the Likelihood Ratio (우도비를 이용한 적응 밴드 분할 기반의 음성 검출기)

  • Kim, Sang-Kyun;Shim, Hyeon-Min;Lee, Sangmin
    • Journal of Korea Multimedia Society
    • /
    • v.17 no.9
    • /
    • pp.1064-1069
    • /
    • 2014
  • In this paper, we propose a novel approach to improve the performance of a voice activity detection(VAD) which is based on the adaptive band-partitioning with the likelihood ratio(LR). The previous method based on the adaptive band-partitioning use the weights that are derived from the variance of the spectral. In our VAD algorithm, the weights are derived from LR, and then the weights are incorporated with the entropy. The proposed algorithm discriminates the voice activity by comparing the weighted entropy with the adaptive threshold. Experimental results show that the proposed algorithm yields better results compared to the conventional VAD algorithms. Especially, the proposed algorithm shows superior improvement in non-stationary noise environments.

Image Be-noising Using Lifting Scheme (Lifting Scheme을 이용한 이미지 잡음 제거)

  • Park, Young-Seok;Kwak, Hoon-Sung
    • Proceedings of the IEEK Conference
    • /
    • 2003.07e
    • /
    • pp.1731-1734
    • /
    • 2003
  • In this paper, we describe an approach for image denoising using the lifting construction, with the spatial adaptive wavelet transform. The adaptive lifting scheme is implemented in spatial domain to be adjusted thresholds to reduce noise. In this approach we represent adaptive characteristics of biorthogonal wavelets for choosing predictors effectively. Predict filter is changed from sample to sample according to local signal features with their vanishing moments. We in this approach have implemented and applied to image denoising by finding a relevant minimax threshold. Experimental results show that the adaptive method of denoising process is compared with existing ones, such as non-adaptive wavelet, CRF(13, 7) and SWE(13, 7) wavelets used by JPEG2000.

  • PDF

Phase boundary estimation with effective initial guess in electrical impedance tomography (전기 임피던스 단층촬영 기법에서 효과적인 초기치 설정을 통한 상 경계 추정)

  • Kim, Bong-Seok;Kim, Sin;Kim, Kyung-Youn
    • Journal of IKEEE
    • /
    • v.16 no.3
    • /
    • pp.211-216
    • /
    • 2012
  • In the phase boundary estimation problem, the estimation performance depends on the initial guess. However, there is no information on the number of bubbles and those positions for the initial guess in real flows. Therefore, it is very important to set appropriate initial guesses from prior information. In this paper, in order to set initial guesses for estimating the phase boundaries in two-phase flows, first, unknown resistivity distribution was estimated using the difference reconstruction method. After that, an adaptive threshold value was automatically computed using intermodes method. Based on this value, the number of bubbles and the initial position were determined. The numerical experiments have been performed to evaluate the estimation performance of the proposed method.

The Adaptive Steganography Using Color Image of Compexity (컬러 이미지의 복잡도를 이용한 적응적 스테가노그라피)

  • Ko, Bong-Soo;Kim, Jang-Hyung;Yang, Dong-Ho
    • Proceedings of the Korea Contents Association Conference
    • /
    • 2006.11a
    • /
    • pp.250-253
    • /
    • 2006
  • In this paper, we proposed a new method of the Adaptive steganography using complexity on bit planes of color image. Applying fixing threshold and variable length, if insert information into all bit plans, all bit plans showed different image quality. Therefore, we first defined the complexity on bit plane and data complexity, similarity insert information into bit plans. As a result, the proposed method increased the insertion capacity and improved the image quality than fixing threshold and variable length method.

  • PDF