• 제목/요약/키워드: Image technique

검색결과 5,841건 처리시간 0.039초

A Novel DWT-SVD Canny-Based Watermarking Using a Modified Torus Technique

  • Lalani, Salima;Doye, D.D.
    • Journal of Information Processing Systems
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    • 제12권4호
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    • pp.681-687
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    • 2016
  • Today's modern world requires a digital watermarking technique that takes the redundancy of an image into consideration for embedding a watermark. The novel algorithm used in this paper takes into consideration the redundancies of spatial domain and wavelet domain for embedding a watermark. Also, the cryptography-based secret key makes the algorithm difficult to hack and help protect ownership. Watermarking is blind, as it does not require the original image. Few coefficient matrices and secret keys are essential to retrieve the original watermark, which makes it redundant to various intentional attacks. The proposed technique resolves the challenge of optimizing transparency and robustness using a Canny-based edge detector technique. Improvements in the transparency of the cover image can be seen in the computed PSNR value, which is 44.20 dB.

Performance Improvement Technique of Long-range Target Information Acquisition for Airborne IR Camera

  • Yang, Hyun-Jin
    • 한국컴퓨터정보학회논문지
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    • 제22권7호
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    • pp.39-45
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    • 2017
  • In this paper, we propose three compensation methods to solve problems in high-resolution airborne infrared camera and to improve long-range target information acquisition performance. First, image motion and temporal noise reduction technique which is caused by atmospheric turbulence. Second, thermal blurring image correction technique by imperfect performance of NUC(Non Uniformity Correction) or raising the internal temperature of the camera. Finally, DRC(Dynamic Range Compression) and flicker removing technique of 14bits HDR(High Dynamic Range) infrared image. Through this study, we designed techniques to improve the acquisition performance of long-range target information of high-resolution airborne infrared camera, and compared and analyzed the performance improvement result with implemented images.

Computational Technique of Volumetric Object Reconstruction in Integral Imaging by Use of Real and Virtual Image Fields

  • Shin, Dong-Hak;Cho, Myung-Jin;Park, Kyu-Chil;Kim, Eun-Soo
    • ETRI Journal
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    • 제27권6호
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    • pp.708-712
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    • 2005
  • We propose a computational reconstruction technique in large-depth integral imaging where the elemental images have information of three-dimensional objects through real and virtual image fields. In the proposed technique, we reconstruct full volume information from the elemental images through both real and virtual image fields. Here, we use uniform mappings of elemental images with the size of the lenslet regardless of the distance between the lenslet array and reconstruction image plane. To show the feasibility of the proposed reconstruction technique, we perform preliminary experiments and present experimental results.

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Clinical Application of Three-Dimensional Reconstruction in Shoulder Surgeries

  • Kim, Sung-Hwan;Ha, Seung-Joo
    • Journal of International Society for Simulation Surgery
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    • 제1권2호
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    • pp.67-70
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    • 2014
  • 3-D medical image reconstruction technique using computer simulation technology has been used in the knowledge of the anatomical features and the biomechanical characteristics with the advancement of computer hardware and software. Especially, the use of 3-D image reconstruction technique in orthopaedics demonstrates that this technique is useful to improve surgical technique as well as to help inform the knowledge of shoulder joint anatomy. The purpose of this article is to introduce the utilization of 3-D image technology in shoulder surgeries.

디지털 화상처리에 의한 해양유출기름확산 계측기법개발에 관한 연구 (A Study on a Development of a Measurement Technique for Diffusion of Oil Spill in the Ocean)

  • 이중우;강신영;도덕희;김기철
    • 한국항만학회지
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    • 제12권2호
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    • pp.291-302
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    • 1998
  • A digital image processing technique which is able to be used for getting the velocity vector distribution of a surface of the spilt oil in the ocean without contacting the flow itself. This technique is based upon the PIV(Particle Imaging Velocimetry) technique and its system mainly consists of a high sensitive camera, a CCD camera, an image grabber, and a host computer in which an image processing algorithm is adopted for velocity vector acquisition. For the acquisition of the advective velocity vector of floating matters on the ocean, a new multi-frame tracking algorithm is proposed, and for the acquisition of the diffusion velocity vector distribution of the spilt oil onto the water surface, a high sensitive gray-level cross-correlation algorithm is proposed.

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Development of Image Processing Technique for Determining Wood Drying Schedules

  • Lee, Hyoung-Woo;Kim, Byung-Nam
    • Journal of the Korean Wood Science and Technology
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    • 제31권6호
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    • pp.15-21
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    • 2003
  • Image processing technique was adapted for exploring the more convenient ways to investigate the drying characteristics of wood. The acquisition of information about drying characteristics is indispensable for the development or improvement of dry-kiln schedules. A small internal fan type wood dry kiln was combined with image-processing and data-acquisition systems to monitor continuously the formation of checks and moisture reduction during drying. All the images and data were analyzed to improve or estimate the dry-kiln schedules and predict the drying time which would be required to dry green wood to 10% moisture content in internal fan type kiln. Samples of 20 mm- and 50 mm-thick Metasequoia glyptostrobodies, Paulownia coreana Uyeki, Pinus densiflora Sieb. Et Zucc., Platanus occidentalis L., Quercus acutissima and Robinia pseudo-acacia were used to verify the potentiality of this technique.

적분 영상을 이용한 고속 비디오 안정화 기법 (Fast Video Stabilization Method Using Integral Image)

  • 권영만;임명재;오병훈
    • 한국인터넷방송통신학회논문지
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    • 제10권5호
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    • pp.13-20
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    • 2010
  • 본 논문에서는 적분 영상(Integral Image)을 이용하여 고속 비디오 안정화를 수행하는 새로운 기법을 제안한다. 제안된 기법에서는 매 프레임마다 적분 영상을 생성하고, 생성된 적분 영상에서 영상의 블록 움직임의 정합을 평가하여 지역 움직임을 추정한다. 이를 사용해서 전역 움직임을 추정하여 보정한다. 제안된 기법의 효율성을 평가하기 실험 데이터를 다양한 패턴으로 직접 제작하였고, 기존 안정화 알고리즘과의 떨림 보정과 수행 시간을 평가하였다. 실험 결과에서 기존 제안한 기법이 기존 방식들에 비해서 수행 시간이 빠르고 떨림을 검출하여 보정함을 확인하였다.

Quantitative Evaluation of Setup Error for Whole Body Stereotactic Radiosurgery by Image Registration Technique

  • Kim, Young-Seok;Yi, Byong-Yong;Kim, Jong-Hoon;Ahn, Seung-Do;Lee, Sang-wook;Im, Ki-Chun;Park, Eun-Kyung
    • 한국의학물리학회:학술대회논문집
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    • 한국의학물리학회 2002년도 Proceedings
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    • pp.103-105
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    • 2002
  • Whole body stereotactic radiosurgery (WBSRS) technique is believed to be useful for the metastatic lesions as well as relatively small primary tumors in the trunk. Unlike stereotactic radiosurgery to intracranial lesion, inherent limitation on immobilization of whole body makes it difficult to achieve the reliable setup reproducibility. For this reason, it is essential to develop an objective and quantitative method of evaluating setup error for WBSRS. An evaluation technique using image registration has been developed for this purpose. Point pair image registrations with WBSRS frame coordinates were performed between two sets of CT images acquired before each treatment. Positional displacements could be determined by means of volumetric planning target volume (PTV) comparison between the reference and the registered image sets. Twenty eight sets of CT images from 19 WBSRS patients treated in Asan Medical Center have been analyzed by this method for determination of setup random error of each treatment. It is objective and clinically useful to analyze setup error quantitatively by image registration technique with WBSRS frame coordinates.

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대용량 이미지넷 인식을 위한 CNN 기반 Weighted 앙상블 기법 (CNN-based Weighted Ensemble Technique for ImageNet Classification)

  • 정희철;최민국;김준광;권순;정우영
    • 대한임베디드공학회논문지
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    • 제15권4호
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    • pp.197-204
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    • 2020
  • The ImageNet dataset is a large scale dataset and contains various natural scene images. In this paper, we propose a convolutional neural network (CNN)-based weighted ensemble technique for the ImageNet classification task. First, in order to fuse several models, our technique uses weights for each model, unlike the existing average-based ensemble technique. Then we propose an algorithm that automatically finds the coefficients used in later ensemble process. Our algorithm sequentially selects the model with the best performance of the validation set, and then obtains a weight that improves performance when combined with existing selected models. We applied the proposed algorithm to a total of 13 heterogeneous models, and as a result, 5 models were selected. These selected models were combined with weights, and we achieved 3.297% Top-5 error rate on the ImageNet test dataset.

High Efficient Entropy Coding For Edge Image Compression

  • Han, Jong-Woo;Kim, Do-Hyun;Kim, Yoon
    • 한국컴퓨터정보학회논문지
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    • 제21권5호
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    • pp.31-40
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    • 2016
  • In this paper, we analyse the characteristics of the edge image and propose a new entropy coding optimized to the compression of the edge image. The pixel values of the edge image have the Gaussian distribution around '0', and most of the pixel values are '0'. By using this analysis, the Zero Block technique is utilized in spatial domain. And the Intra Prediction Mode of the edge image is similar to the mode of the surrounding blocks or likely to be the Planar Mode or the Horizontal Mode. In this paper, we make use of the MPM technique that produces the Intra Prediction Mode with high probability modes. By utilizing the above properties, we design a new entropy coding method that is suitable for edge image and perform the compression. In case the existing compression techniques are applied to edge image, compression ratio is low and the algorithm is complicated as more than necessity and the running time is very long, because those techniques are based on the natural images. However, the compression ratio and the running time of the proposed technique is high and very short, respectively, because the proposed algorithm is optimized to the compression of the edge image. Experimental results indicate that the proposed algorithm provides better visual and PSNR performance up to 11 times than the JPEG.