• 제목/요약/키워드: image of science

검색결과 9,961건 처리시간 0.043초

영상처리기법을 이용한 균열 진전 측정시스템 개발 (Development of Measurement System for Crack Growth Using Image Processing Technology)

  • 류대현;남승훈;김용일;김시천
    • 한국안전학회지
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    • 제17권4호
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    • pp.11-18
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    • 2002
  • We proposed a new experimental method which is required to easily observe the growth behavior of fatigue cracks. In the proposed method, the image data of cracks were stored into the computer while the cyclic loading was interrupted. After testing, crack length was determined using an image processing software which was developed by authors. By comparing the data measured by the image processing system with those by the manual measurement with a microscope, the effectiveness of the image processing system was established. If the proposed method is used to monitor and observe the crack growth behavior automatically, the time and efforts for fatigue test could be dramatically reduced.

위변조 검출을 위한 SVD 디지털 이미지 포렌직 (SVD-Based Digital Image Forensics for Detecting Tampering)

  • 송근실;김미애;이원형
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2006년도 하계종합학술대회
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    • pp.377-378
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    • 2006
  • The proposed method measures the correlation maps of SVD that are used to interpret data relations and structures between the original image and the distorted image. It seems that the SVD results can be used to assist us in gaining information about covariance structure of two images. This method is able to work in the complete absence of any digital watermark or signature. The effectiveness of this method is seen through testing the robustness against JPEG compression.

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Image Retrieval Using Space-Distributed Average Coordinates

  • H. W. Chang;E. K. Kang;Park, J. S.
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 ITC-CSCC -2
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    • pp.894-897
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    • 2000
  • In this paper, we present a content-based image retrieval method that is less sensitive to some rotations and translations of an image by using the fuzzy region segmentation. The algorithm retrieves similar images from a database using the two features of color and color spatial information. To index images, we use the average coordinates of color distribution to obtain the spatial information of each segmented region. Furthermore, we also propose the alternative to the ripple phenomenon, which is occurred in the conventional fuzzy region segmentation algorithm.

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A Method of Coupling Expected Patch Log Likelihood and Guided Filtering for Image De-noising

  • Wang, Shunfeng;Xie, Jiacen;Zheng, Yuhui;Wang, Jin;Jiang, Tao
    • Journal of Information Processing Systems
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    • 제14권2호
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    • pp.552-562
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    • 2018
  • With the advent of the information society, image restoration technology has aroused considerable interest. Guided image filtering is more effective in suppressing noise in homogeneous regions, but its edge-preserving property is poor. As such, the critical part of guided filtering lies in the selection of the guided image. The result of the Expected Patch Log Likelihood (EPLL) method maintains a good structure, but it is easy to produce the ladder effect in homogeneous areas. According to the complementarity of EPLL with guided filtering, we propose a method of coupling EPLL and guided filtering for image de-noising. The EPLL model is adopted to construct the guided image for the guided filtering, which can provide better structural information for the guided filtering. Meanwhile, with the secondary smoothing of guided image filtering in image homogenization areas, we can improve the noise suppression effect in those areas while reducing the ladder effect brought about by the EPLL. The experimental results show that it not only retains the excellent performance of EPLL, but also produces better visual effects and a higher peak signal-to-noise ratio by adopting the proposed method.

Research on Multiple-image Encryption Scheme Based on Fourier Transform and Ghost Imaging Algorithm

  • Zhang, Leihong;Yuan, Xiao;Zhang, Dawei;Chen, Jian
    • Current Optics and Photonics
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    • 제2권4호
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    • pp.315-323
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    • 2018
  • A new multiple-image encryption scheme that is based on a compressive ghost imaging concept along with a Fourier transform sampling principle has been proposed. This further improves the security of the scheme. The scheme adopts a Fourier transform to sample the original multiple-image information respectively, utilizing the centrosymmetric conjugation property of the spatial spectrum of the images to obtain each Fourier coefficient in the most abundant spatial frequency band. Based on this sampling principle, the multiple images to be encrypted are grouped into a combined image, and then the compressive ghost imaging algorithm is used to improve the security, which reduces the amount of information transmission and improves the information transmission rate. Due to the presence of the compressive sensing algorithm, the scheme improves the accuracy of image reconstruction.

Adaptive Importance Channel Selection for Perceptual Image Compression

  • He, Yifan;Li, Feng;Bai, Huihui;Zhao, Yao
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제14권9호
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    • pp.3823-3840
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    • 2020
  • Recently, auto-encoder has emerged as the most popular method in convolutional neural network (CNN) based image compression and has achieved impressive performance. In the traditional auto-encoder based image compression model, the encoder simply sends the features of last layer to the decoder, which cannot allocate bits over different spatial regions in an efficient way. Besides, these methods do not fully exploit the contextual information under different receptive fields for better reconstruction performance. In this paper, to solve these issues, a novel auto-encoder model is designed for image compression, which can effectively transmit the hierarchical features of the encoder to the decoder. Specifically, we first propose an adaptive bit-allocation strategy, which can adaptively select an importance channel. Then, we conduct the multiply operation on the generated importance mask and the features of the last layer in our proposed encoder to achieve efficient bit allocation. Moreover, we present an additional novel perceptual loss function for more accurate image details. Extensive experiments demonstrated that the proposed model can achieve significant superiority compared with JPEG and JPEG2000 both in both subjective and objective quality. Besides, our model shows better performance than the state-of-the-art convolutional neural network (CNN)-based image compression methods in terms of PSNR.

Single Image Enhancement Using Inter-channel Correlation

  • Kim, Jin;Jeong, Soowoong;Kim, Yong-Ho;Lee, Sangkeun
    • IEIE Transactions on Smart Processing and Computing
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    • 제2권3호
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    • pp.130-139
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    • 2013
  • This paper proposes a new approach for enhancing digital images based on red channel information, which has the most analogous characteristics to invisible infrared rays. Specifically, a red channel in RGB space is used to analyze the image contents and improve the visual quality of the input images but it can cause unexpected problems, such as the over-enhancement of reddish input images. To resolve this problem, inter-channel correlations between the color channels were derived, and the weighting parameters for visually pleasant image fusion were estimated. Applying the parameters resulted in significant brightness as well as improvement in the dark and bright regions. Furthermore, simple contrast and color corrections were used to maintain the original contrast level and color tone. The main advantages of the proposed algorithm are 1) it can improve a given image considerably with a simple inter-channel correlation, 2) it can obtain a similar effect of using an extra infrared image, and 3) it is faster than other algorithms compared without artifacts including halo effects. The experimental results showed that the proposed approach could produce better natural images than the existing enhancement algorithms. Therefore, the proposed scheme can be a useful tool for improving the image quality in consumer imaging devices, such as compact cameras.

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움직임 실루엣 영상의 일반적인 표현 방식에 대한 연구 (A General Representation of Motion Silhouette Image: Generic Motion Silhouette Image(GMSI))

  • 홍성준;이희성;김은태
    • 제어로봇시스템학회논문지
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    • 제13권8호
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    • pp.749-753
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    • 2007
  • In this paper, a generalized version of the Motion Silhouette Image(MSI) called the Generic Motion Silhouette Image (GMSI) is proposed for gait recognition. The GMSI is a gray-level image and involves the spatiotemporal information of individual motion. The GMSI not only generalizes the MSI but also reflects a flexible feature of a gait sequence. Along with the GMSI, we use the Principal Component Analysis(PCA) to reduce the dimensionality of the GMSI and the Nearest Neighbor(NN) for classification. We apply the proposed feature to NLPR database and compare it with the conventional MSI. Experimental results show the effectiveness of the GMSI.

Image recognition technology in rotating machinery fault diagnosis based on artificial immune

  • Zhu, Dachang;Feng, Yanping;Chen, Qiang;Cai, Jinbao
    • Smart Structures and Systems
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    • 제6권4호
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    • pp.389-403
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    • 2010
  • By using image recognition technology, this paper presents a new fault diagnosis method for rotating machinery with artificial immune algorithm. This method focuses on the vibration state parameter image. The main contribution of this paper is as follows: firstly, 3-D spectrum is created with raw vibrating signals. Secondly, feature information in the state parameter image of rotating machinery is extracted by using Wavelet Packet transformation. Finally, artificial immune algorithm is adopted to diagnose rotating machinery fault. On the modeling of 600MW turbine experimental bench, rotor's normal rate, fault of unbalance, misalignment and bearing pedestal looseness are being examined. It's demonstrated from the diagnosis example of rotating machinery that the proposed method can improve the accuracy rate and diagnosis system robust quality effectively.