• Title/Summary/Keyword: Correction algorithm

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Precision correction of satellite-based linear pushbroom-type CCD camera images (선형 CCD카메라 영상의 정밀 기하학적 보정)

  • 신동석;이영란;이흥규
    • Korean Journal of Remote Sensing
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    • v.14 no.2
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    • pp.137-148
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    • 1998
  • An algorithm developed for the precision correction of high resolution satellite images is introduced in this paper. In general, the polynomial warping algorithm which derives polynomial equations between GCPs extracted from an image and a base map requires many GCPs well-distributed over the image. The precision correction algorithm described in this paper is based on a sensor-orbit-Earth geometry, and therefore, it is capable of correcting a raw image using only 2-3 GCPs. This algorithm estimates the errors on the orbit determination and the attitude of the satellite by using a Kalman filter. This algorithm was implemented, tested and integrated into the KITSAT-3 image preprocessing software.

Enhanced Urban Information Recognition through Correction of Shadow Effects (그림자효과 보정을 통한 향상된 도시정보 인식)

  • 손홍규;윤공현;박효근
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2003.04a
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    • pp.187-190
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    • 2003
  • Due to complexity of diverse features in urban area, accurate feature extraction is laborious task in aerial and satellite imagery. Especially occlusion by buildings, and image distortion of shadow effects make processing more difficult work. In this study, algorithm was presented to correct of shadow effects in aerial color images. This algorithm enables user to accurately interpretate urban information by correction of shadow effects in aerial color images

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A study on Improvement for distorted images of the Digital X-ray Scanner System based on Fuzzy Correction Algorithm

  • Baek, Jae-Ho;Kim, Kyung-Jung;Park, Mi-Gnon
    • Proceedings of the Korea Society of Information Technology Applications Conference
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    • 2005.11a
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    • pp.173-176
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    • 2005
  • This paper proposes a fuzzy correction algorithm that can correct the distorted medical image caused by the scanning nonlinear velocity of the Digital X-ray Scanner System (DX-Scanner) using the Multichannel Ionization Chamber (MIC). In the DX-Scanner, the scanned medical image is distorted for reasons of unsuitable integration time at the nonlinear acceleration period of the AC servo motor during the inspection of patients. The proposed algorithm finds the nonlinear motor velocity modeling through fuzzy system by clustering and reconstructs the normal medical image lines by calculating the suitable moving distance with the velocity of the motor using the modeling, acceleration time and integration time. In addition, several image processing is included in the algorithm. This algorithm analyzes exact pixel lines by comparing the distance of the acceleration period with the distance of the uniform velocity period in every integration time and is able to compensate for the velocity of the acceleration period. By applying the proposed algorithm to the test pattern for checking the image resolution, the effectiveness of this algorithm is verified. The corrected image obtained from distorted image is similar to the normal and better image for a doctor's diagnosis.

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Scene-based Nonuniformity Correction for Neural Network Complemented by Reducing Lense Vignetting Effect and Adaptive Learning rate

  • No, Gun-hyo;Hong, Yong-hee;Park, Jin-ho;Jhee, Ho-jin
    • Journal of the Korea Society of Computer and Information
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    • v.23 no.7
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    • pp.81-90
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    • 2018
  • In this paper, reducing lense Vignetting effect and adaptive learning rate method are proposed to complement Scribner's neural network for nuc algorithm which is the effective algorithm in statistic SBNUC algorithm. Proposed reducing vignetting effect method is updated weight and bias each differently using different cost function. Proposed adaptive learning rate for updating weight and bias is using sobel edge detection method, which has good result for boundary condition of image. The ordinary statistic SBNUC algorithm has problem to compensate lense vignetting effect, because statistic algorithm is updated weight and bias by using gradient descent method, so it should not be effective for global weight problem same like, lense vignetting effect. We employ the proposed methods to Scribner's neural network method(NNM) and Torres's reducing ghosting correction for neural network nuc algorithm(improved NNM), and apply it to real-infrared detector image stream. The result of proposed algorithm shows that it has 10dB higher PSNR and 1.5 times faster convergence speed then the improved NNM Algorithm.

COMPARISON OF ATMOSPHERIC CORRECTION ALGORITHMS FOR DERIVING SEA SURFACE TEMPERATURE AROUND THE KOREAN SEA AREA USING NOAA/AVHRR DATA

  • Yoon, Suk;Ahn, Yu-Hwan;Ryu, Joo-Hyung;Won, Joong-Sun
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.518-521
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    • 2007
  • To retrieve Sea Surface Temperature(SST) from NOAA-AVHRR imagery the spilt window atmospheric correction algorithm is generally used. Recently, there have been various new algorithms developed to process these data, namely the variable-coefficient split-window, the R54 transmittance-ratio method, fixed-coefficient nonlinear algorithm, dynamic water vapour (DWV) correction method, Dynamic Water Vapour and Temperature algorithm (DWVT). We used MCSST (Multi-Channel Sea surface temperature) and NLSST(Non linear sea surface temperature) algorithms in this study. The study area is around the Korea sea area (Yellow Sea). We compared and analyzed with various methods by applying each Ocean in-situ data and satellite data. The primary aim of study is to verify and optimize algorithms. Finally, this study proposes an optimized algorithm for SST retrieval.

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A Study on Object Detection in Region-of-Interest Algorithm using Adjacent Frames based Image Correction Algorithm for Interactive Building Signage

  • Lee, Jonghyeok;Choi, Jinyeong;Cha, Jaesang
    • International Journal of Internet, Broadcasting and Communication
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    • v.10 no.2
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    • pp.74-78
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    • 2018
  • Recently, due to decrease hardware prices and the development of technology, analog signage has been changing to digital signage for providing content such as advertisements, videos. Furthermore, in order to provide advertisements and contents to users more effectively, technical researches are being conducted in various industries. In addition, including digital signage that uses displays, it can be seen that it provides advertisements and contents using diverse devices such as LED signage, smart pads, and smart phones. However, most digital signage is installed in one place to provide contents and provides interactivity through simple events such as manual content provision or touch. So, in this paper, we suggest a new object detection algorithm based on an adjacent frames based image correction algorithm for interactive building signage.

A New Approach on the Correction for Compton Escape Component in X-Ray Unfolding Algorithm

  • Kim, Soon-Young;Kim, Jong-Kyung
    • Proceedings of the Korean Nuclear Society Conference
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    • 1995.05a
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    • pp.925-930
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    • 1995
  • A new approach on the correction for Compton escape component in X-ray unfolding algorithm was investigated to obtain more accurate X-ray source spectrum. The X-ray detector used in this study was a planar type HPGe detector(EG&G ORTEC, GLP-32340/13-P-LP) whose energy response has been blown and ISO narrow beam series were employed as source spectrum. At lower energy Part of measured X-ray spectrum including the correction for Compton escape component more accurate unfolded spectrum was obtained by letting down the starting energy level of the collection in existing spectrum correction procedure to consider multiple scattering effects. It is, from this study, concluded that accurate correction for Compton escape component is needed in X-ray unfolding procedure since Compton scattering becomes more important as incident X-ray energies increase.

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Blind QR Code Steganographic Approach Based upon Error Correction Capability

  • Chiang, Yin-Jen;Lin, Pei-Yu;Wang, Ran-Zan;Chen, Yi-Hui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.10
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    • pp.2527-2543
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    • 2013
  • A novel steganographic QR code algorithm, which not only coveys the secret into the widely-used QR barcode but also preserves the readability of QR content and the capability of error correction, is presented in this article. Different from the conventional applications for QR barcode, the designed algorithm conceals the secret into the QR modules directly by exploiting the error correction capability. General browsers can read the QR content from the QR code via barcode readers; however, only the authorized receiver can further reveal the secret from the QR code directly. The new mechanism can convey a larger secret payload along with adjustment of the QR version and error correction level. Moreover, the blind property allows the receiver to reveal the secret without the knowledge of the embedded position of modules. Experimental results demonstrate that the new algorithm is secure, efficient and feasible for the low-power QR readers and mobile devices.

Key-word Error Correction System using Syllable Restoration Algorithm (음절 복원 알고리즘을 이용한 핵심어 오류 보정 시스템)

  • Ahn, Chan-Shik;Oh, Sang-Yeob
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.10
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    • pp.165-172
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    • 2010
  • There are two method of error correction in vocabulary recognition system. one error pattern matting base on method other vocabulary mean pattern base on method. They are a failure while semantic of key-word problem for error correction. In improving, in this paper is propose system of key-word error correction using algorithm of syllable restoration. System of key-word error correction by processing of semantic parse through recognized phoneme meaning. It's performed restore by algorithm of syllable restoration phoneme apply fluctuation before word. It's definitely parse of key-word and reduced of unrecognized. Find out error correction rate using phoneme likelihood and confidence for system parse. When vocabulary recognition perform error correction for error proved vocabulary. system performance comparison as a result of recognition improve represent 2.3% by method using error pattern learning and error pattern matting, vocabulary mean pattern base on method.

Development of Hybrid Vision Correction Algorithm (Hybrid Vision Correction Algorithm의 개발)

  • Ryu, Yong Min;Lee, Eui Hoon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.1
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    • pp.61-73
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    • 2021
  • Metaheuristic search methods have been developed to solve problems with a range of purpose functions in situations lacking information and time constraints. In this study, the Hybrid Vision Correction Algorithm (HVCA), which enhances the performance of the Vision Correction Algorithm (VCA), was developed. The HVCA has applied two methods to improve the performance of VCA. The first method changes the parameters required by the user for self-adaptive parameters. The second method, the CGS structure of the Exponential Bandwidth Harmony Search With a Centralized Global Search (EBHS-CGS), was added to the HVCA. The HVCA consists of two structures: CGS and VCA. To use the two structures, a method was applied to increase the probability of selecting the structure with the optimal value as it was performed. The optimization problem was applied to determine the performance of the HVCA, and the results were compared with Harmony Search (HS), Improved Harmony Search (IHS), and VCA. The HVCA improved the number of times to find the optimal value during 100 repetitions compared to HS, IHS, and VCA. Moreover, the HVCA reduced the Number of Function Evaluations (NFEs). Therefore, the performance of the HVCA has been improved.