• Title/Summary/Keyword: Robust detector

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Robust Lane Detection Method Under Severe Environment (악 조건 환경에서의 강건한 차선 인식 방법)

  • Lim, Dong-Hyeog;Tran, Trung-Thien;Cho, Sang-Bock
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.5
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    • pp.224-230
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    • 2013
  • Lane boundary detection plays a key role in the driver assistance system. This study proposes a robust method for detecting lane boundary in severe environment. First, a horizontal line detects form the original image using improved Vertical Mean Distribution Method (iVMD) and the sub-region image which is under the horizontal line, is determined. Second, we extract the lane marking from the sub-region image using Canny edge detector. Finally, K-means clustering algorithm classifi left and right lane cluster under variant illumination, cracked road, complex lane marking and passing traffic. Experimental results show that the proposed method satisfie the real-time and efficient requirement of the intelligent transportation system.

A Multi-Stage Approach to Secure Digital Image Search over Public Cloud using Speeded-Up Robust Features (SURF) Algorithm

  • AL-Omari, Ahmad H.;Otair, Mohammed A.;Alzwahreh, Bayan N.
    • International Journal of Computer Science & Network Security
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    • v.21 no.12
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    • pp.65-74
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    • 2021
  • Digital image processing and retrieving have increasingly become very popular on the Internet and getting more attention from various multimedia fields. That results in additional privacy requirements placed on efficient image matching techniques in various applications. Hence, several searching methods have been developed when confidential images are used in image matching between pairs of security agencies, most of these search methods either limited by its cost or precision. This study proposes a secure and efficient method that preserves image privacy and confidentially between two communicating parties. To retrieve an image, feature vector is extracted from the given query image, and then the similarities with the stored database images features vector are calculated to retrieve the matched images based on an indexing scheme and matching strategy. We used a secure content-based image retrieval features detector algorithm called Speeded-Up Robust Features (SURF) algorithm over public cloud to extract the features and the Honey Encryption algorithm. The purpose of using the encrypted images database is to provide an accurate searching through encrypted documents without needing decryption. Progress in this area helps protect the privacy of sensitive data stored on the cloud. The experimental results (conducted on a well-known image-set) show that the performance of the proposed methodology achieved a noticeable enhancement level in terms of precision, recall, F-Measure, and execution time.

Robust spectrum sensing under noise uncertainty for spectrum sharing

  • Kim, Chang-Joo;Jin, Eun Sook;Cheon, Kyung-yul;Kim, Seon-Hwan
    • ETRI Journal
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    • v.41 no.2
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    • pp.176-183
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    • 2019
  • Spectrum sensing plays an important role in spectrum sharing. Energy detection is generally used because it does not require a priori knowledge of primary user (PU) signals; however, it is sensitive to noise uncertainty. An order statistics (OS) detector provides inherent protection against nonhomogeneous background signals. However, no analysis has been conducted yet to apply OS detection to spectrum sensing in a wireless channel to solve noise uncertainty. In this paper, we propose a robust spectrum sensing scheme based on generalized order statistics (GOS) and analyze the exact false alarm and detection probabilities under noise uncertainty. From the equation of the exact false alarm probability, the threshold value is calculated to maintain a constant false alarm rate. The detection probability is obtained from the calculated threshold under noise uncertainty. As a fusion rule for cooperative spectrum sensing, we adopt an OR rule, that is, a 1-out-of-N rule, and we call the proposed scheme GOS-OR. The analytical results show that the GOS-OR scheme can achieve optimum performance and maintain the desired false alarm rates if the coefficients of the GOS-OR detector can be correctly selected.

A Computer Vision-Based Banknote Recognition System for the Blind with an Accuracy of 98% on Smartphone Videos

  • Sanchez, Gustavo Adrian Ruiz
    • Journal of the Korea Society of Computer and Information
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    • v.24 no.6
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    • pp.67-72
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    • 2019
  • This paper proposes a computer vision-based banknote recognition system intended to assist the blind. This system is robust and fast in recognizing banknotes on videos recorded with a smartphone on real-life scenarios. To reduce the computation time and enable a robust recognition in cluttered environments, this study segments the banknote candidate area from the background utilizing a technique called Pixel-Based Adaptive Segmenter (PBAS). The Speeded-Up Robust Features (SURF) interest point detector is used, and SURF feature vectors are computed only when sufficient interest points are found. The proposed algorithm achieves a recognition accuracy of 98%, a 100% true recognition rate and a 0% false recognition rate. Although Korean banknotes are used as a working example, the proposed system can be applied to recognize other countries' banknotes.

Study of the Haar Wavelet Feature Detector for Image Retrieval (이미지 검색을 위한 Haar 웨이블릿 특징 검출자에 대한 연구)

  • Peng, Shao-Hu;Kim, Hyun-Soo;Muzzammil, Khairul;Kim, Deok-Hwan
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.47 no.1
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    • pp.160-170
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    • 2010
  • This paper proposes a Haar Wavelet Feature Detector (HWFD) based on the Haar wavelet transform and average box filter. By decomposing the original image using the Haar wavelet transform, the proposed detector obtains the variance information of the image, making it possible to extract more distinctive features from the original image. For detection of interest points that represent the regions whose variance is the highest among their neighbor regions, we apply the average box filter to evaluate the local variance information and use the integral image technique for fast computation. Due to utilization of the Haar wavelet transform and the average box filter, the proposed detector is robust to illumination change, scale change, and rotation of the image. Experimental results show that even though the proposed method detects fewer interest points, it achieves higher repeatability, higher efficiency and higher matching accuracy compared with the DoG detector and Harris corner detector.

Development of a New Vehicle Detector Combining CW Radar and Magnetometer Techniques (CW 레이다와 자계기술을 복합한 새로운 차량검지기 개발)

  • 정재영;김인석
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.10 no.4
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    • pp.564-581
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    • 1999
  • This paper introduces a new, small, low cost, robust and quick replaceable pavement-based vehicle detector using CW radar, magnetometer, and UHF small antennal techniques. The detector has been developed for a replacement of loop detectors having wide surface areas, for a more accurate operation under all weather conditions, and for no algorithmic change of the existing traffic information system. The detected vehicle information is sent by a small helical antenna embedded in a plastic material and received by a 5/8 $\lambda$ long GP antenna for signal processing. In a relatively good weather condition, the detector operates at 24 GHz. But in a heavy rain condition, magnetometer is activated by automatic switching.

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Robust Viewpoint Estimation Algorithm for Moving Parallax Barrier Mobile 3D Display (이동형 패럴랙스 배리어 모바일 3D 디스플레이를 위한 강인한 시청자 시역 위치 추정 알고리즘)

  • Kim, Gi-Seok;Cho, Jae-Soo;Um, Gi-Mun
    • Journal of Broadcast Engineering
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    • v.17 no.5
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    • pp.817-826
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    • 2012
  • This paper presents a robust viewpoint estimation algorithm for Moving Parallax Barrier mobile 3D display in sudden illumination changes. We analyze the previous viewpoint estimation algorithm that consists of the Viola-Jones face detector and the feature tracking by the Optical-Flow. The sudden changes in illumination decreases the performance of the Optical-flow feature tracker. In order to solve the problem, we define a novel performance measure for the Optical-Flow tracker. The overall performance can be increased by the selective adoption of the Viola-Jones detector and the Optical-flow tracker depending on the performance measure. Various experimental results show the effectiveness of the proposed method.

A Robust Decorrelating Multiuser Detector for Asynchronous DS/CDMA Communication Systems (비동기 DS/CDMA 시스템을 위한 역상관 다중사용자 검출기)

  • Yoon, Seok-Hyun;Lee, Kyung-Ha;Hong, Kwang-Seok
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.35S no.6
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    • pp.1-8
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    • 1998
  • This paper presents an asynchronous DS/CDMA multiuser detector, which is a two stage, symbol-by-symbol scheme consisting of conventional detectors followed by linear decorrelating detectors. The conventional detector first makes temporal decisions and the detected symbols are delayed by one symbol period to be used for the selection of decorrelating bases in the subsequent decorrelaing detection stage. It also employs a bank of early-late correlators in place of a bank of single correlators taking the small offset of chip timing asynchronism into account. The proposed detector requires only the coarse knowledge of relative time delays of interfering users and is suitable for digital implementation. To verify the detector performance, the analytical BER performance will be given and compared with the simulation results for BPSK DS/CDMA signals in AWGN channel. While the performance of the proposed detector will be analyzed for time-limited signal, the simulation is carried out for both the time-limited and band-limited signals. As can be seen in the simulation results, the proposed scheme shows good results.

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Calculation of Detector Positions for a Source Localizing Radiation Portal Monitor System Using a Modified Iterative Genetic Algorithm

  • Jeon, Byoungil;Kim, Jongyul;Lim, Kiseo;Choi, Younghyun;Moon, Myungkook
    • Journal of Radiation Protection and Research
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    • v.42 no.4
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    • pp.212-221
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    • 2017
  • Background: This study aims to calculate detector positions as a design of a radioactive source localizing radiation portal monitor (RPM) system using an improved genetic algorithm. Materials and Methods: To calculate of detector positions for a source localizing RPM system optimization problem is defined. To solve the problem, a modified iterative genetic algorithm (MIGA) is developed. In general, a genetic algorithm (GA) finds a globally optimal solution with a high probability, but it is not perfect at all times. To increase the probability to find globally optimal solution rather, a MIGA is designed by supplementing the iteration, competition, and verification with GA. For an optimization problem that is defined to find detector positions that maximizes differences of detector signals, a localization method is derived by modifying the inverse radiation transport model, and realistic parameter information is suggested. Results and Discussion: To compare the MIGA and GA, both algorithms are implemented in a MATLAB environment. The performance of the GA and MIGA and that of the procedures supplemented in the MIGA are analyzed by computer simulations. The results show that the iteration, competition, and verification procedures help to search for globally optimal solutions. Further, the MIGA is more robust against falling into local minima and finds a more reliably optimal result than the GA. Conclusion: The positions of the detectors on an RPM for radioactive source localization are optimized using the MIGA. To increase the contrast of the measurements from each detector, a relationship between the source and the detectors is derived by modifying the inverse transport model. Realistic parameters are utilized for accurate simulations. Furthermore, the MIGA is developed to achieve a reliable solution. By utilizing results of this study, an RPM for radioactive source localization has been designed and will be fabricated soon.

Feature Matching Algorithm Robust To Noise (잡음에 강인한 특징점 정합 기법)

  • Jung, Hyunjo;Yoo, Jisang
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2015.07a
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    • pp.9-12
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    • 2015
  • In this paper, we propose a new feature matching algorithm by modifying and combining the FAST(Features from Accelerated Segment Test) feature detector and SURF feature descriptor which is robust to the distortion of the given image. Scale space is generated to consider the variation of the scale and determine the candidate of features in the image robust to the noise. The original FAST algorithm results in many feature points along edges. To solve this problem, we apply the principal curvatures for refining it. We also use SURF descriptor to make it robust against the variations in the image by rotation. Through the experiments, it is shown that the proposed algorithm has better performance than the conventional feature matching algorithms even though it has much less computational load. Especially, it shows a strength for noisy images.

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