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Application of Hydroacoustic System and Kompsat-2 Image to Estimate Distribution of Seagrass Beds (수중음향과 Kompsat-2 위성영상을 이용한 해초지 분포 추정)

  • Kim, Keunyong;Eom, Jinah;Choi, Jong-Kuk;Ryu, Joo-Hyung;Kim, Kwang Yong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.17 no.3
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    • pp.181-188
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    • 2012
  • Despite the ecological importance of seagrass beds, their distributional information in Korean coastal waters is insufficient. Therefore, we used hydroacoustic system to collect accurate bathymetry and classification of seagrass, and Kompsat-2 (4 m spatial resolution) image for detection of seagrass beds at Deukryang Bay, Korea. The accuracy of Kompsat-2 image classification was evaluated using hydracoustic survey result using error matrix and Kappa value. The total area of seagrass beds from satellite image classification was underestimated compared to the hydroacoustic survey, estimated 3.9 and $4.5km^2$ from satellite image and hydroacoustic data, respectively. Nonetheless, the accuracy of Kompsat-2 image classification over hydroacoustic-based method showing 90% (Kappa=0.85) for the three class maps (seagrass, unvegetated seawater and aquaculture). The agreement between the satellite image classification and the hydroacoustic result was 77.1% (the seagrass presence/absence map). From our result of satellite image classification, Kompsat-2 image is suitable for mapping seagrass beds with high accuracy and non-destructive method. For more accurate information, more researches with a variety of high-resolution satellite image will be preceded.

Purple Image and Formative Properties in the Contemporary Fashion (현대(現代)패션에 나타난 Purple의 조형성(造形性)과 이미지)

  • Kim, Bong-Ju;Lee, Kyoung-Hee
    • Journal of Fashion Business
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    • v.6 no.4
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    • pp.163-172
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    • 2002
  • The purpose of this study is to investigate purple image and formative properties in contemporary fashion. For the study of formative properties 152 kinds of costume samples from photographs in fashion magazines. For the study of image 40 kinds of costume samples is used and divided into tones : pale(Vp, Lgr, L), bright(P, B), vivid(S, V, Dp), dark(Gr, Dl, Dgr, Dk). A total 24 pairs of abjective words were used to measure the semantic differential scale in this study. The data were analyzed by factor analysis, ANOVA, MDS and regression analysis. The results are as follows; 1. Factor analysis has extracted 5 factors which consist of purple image in contemporary fashion. The factors are high quality, hardness and softness, simplicity, temperature, maturity. 2. There were significant differences in visual evaluation of purple tones. 3. The discrimination among. 4 purple tones was related to weight of purple 4. The evaluative dimensions of purple image in modern fashion were identified by Light - Heavy and Pale - Strong. 5. The image effect on Preference, Buying needs, Pleasant and Riches was consist of complicated sensibility.

PPD: A Robust Low-computation Local Descriptor for Mobile Image Retrieval

  • Liu, Congxin;Yang, Jie;Feng, Deying
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.4 no.3
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    • pp.305-323
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    • 2010
  • This paper proposes an efficient and yet powerful local descriptor called phase-space partition based descriptor (PPD). This descriptor is designed for the mobile image matching and retrieval. PPD, which is inspired from SIFT, also encodes the salient aspects of the image gradient in the neighborhood around an interest point. However, without employing SIFT's smoothed gradient orientation histogram, we apply the region based gradient statistics in phase space to the construction of a feature representation, which allows to reduce much computation requirements. The feature matching experiments demonstrate that PPD achieves favorable performance close to that of SIFT and faster building and matching. We also present results showing that the use of PPD descriptors in a mobile image retrieval application results in a comparable performance to SIFT.

Design of Block-based Image Descriptor using Local Color and Texture (지역 칼라와 질감을 활용한 블록 기반 영상 검색 기술자 설계)

  • Park, Sung-Hyun;Lee, Yong-Hwan;Kim, Youngseop
    • Journal of the Semiconductor & Display Technology
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    • v.12 no.4
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    • pp.33-38
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    • 2013
  • Image retrieval is one of the most exciting and fastest growing research fields in the area of multimedia technology. As the amount of digital contents continues to grow users are experiencing increasing difficulty in finding specific images in their image libraries. This paper proposes an efficient image descriptor which uses a local color and texture in the non-overlapped block images. To evaluate the performance of the proposed method, we assessed the retrieval efficiency in terms of ANMRR with common image dataset. The experimental trials revealed that the proposed algorithm exhibited a significant improvement in ANMRR, compared to Dominant Color Descriptor and Edge Histogram Descriptor.

Fake Iris Image Detection based on Watermark

  • Kim, Man-Ki;Lee, Samuel;Kim, Gye-Young
    • Journal of the Korea Society of Computer and Information
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    • v.23 no.4
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    • pp.33-39
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    • 2018
  • In this paper, we propose a describes how to detect a false iris image by inserting watermark into a iris image. The existing method, which inserts the watermark into the entire iris image to detect a fake iris, has a problem that can evade it by segmenting iris region of an iris image. The purpose of overcoming the problem, this paper proposes a new fake iris detection technique based on digital watermark. It first searches a central point of an iris image, divide the image into blocks with respect to the point. executes Discrete Cosine Transform, inserts watermark into the blocks, and then verifies an iris image using NC(Normalized Correlation). In the experiments, we confirm the robustness for attacks - crop and JPEG.

Development of Image Process for Crack Identification on Porcelain Insulators (자기애자의 자기부 균열 식별을 위한 이미지 처리기법 개발)

  • Choi, In-Hyuk;Shin, Koo-Yong;An, Ho-Song;Koo, Ja-Bin;Son, Ju-Am;Lim, Dae-Yeon;Oh, Tae-Keun;Yoon, Young-Geun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.33 no.4
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    • pp.303-309
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    • 2020
  • This study proposes a crack identification algorithm to analyze the surface condition of porcelain insulators and to efficiently visualize cracks. The proposed image processing algorithm for crack identification consists of two primary steps. In the first step, the brightness is eliminated by converting the image to the lab color space. Then, the background is removed by the K-means clustering method. After that, the optimum image treatment is applied using morphological image processing and median filtering to remove unnecessary noise, such as blobs. In the second step, the preprocessed image is converted to grayscale, and any cracks present in the image are identified. Next, the region properties, such as the number of pixels and the ratio of the major to the minor axis, are used to separate the cracks from the noise. Using this image processing algorithm, the precision of crack identification for all the sample images was approximately 80%, and the F1 score was approximately 70. Thus, this method can be helpful for efficient crack monitoring.

Adaptive Noise Reduction Algorithm for an Image Based on a Bayesian Method

  • Kim, Yeong-Hwa;Nam, Ji-Ho
    • Communications for Statistical Applications and Methods
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    • v.19 no.4
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    • pp.619-628
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    • 2012
  • Noise reduction is an important issue in the field of image processing because image noise lowers the quality of the original pure image. The basic difficulty is that the noise and the signal are not easily distinguished. Simple smoothing is the most basic and important procedure to effectively remove the noise; however, the weakness is that the feature area is simultaneously blurred. In this research, we use ways to measure the degree of noise with respect to the degree of image features and propose a Bayesian noise reduction method based on MAP (maximum a posteriori). Simulation results show that the proposed adaptive noise reduction algorithm using Bayesian MAP provides good performance regardless of the level of noise variance.

A FAST AND ACCURATE NUMERICAL METHOD FOR MEDICAL IMAGE SEGMENTATION

  • Li, Yibao;Kim, Jun-Seok
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.14 no.4
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    • pp.201-210
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    • 2010
  • We propose a new robust and accurate method for the numerical solution of medical image segmentation. The modified Allen-Cahn equation is used to model the boundaries of the image regions. Its numerical algorithm is based on operator splitting techniques. In the first step of the splitting scheme, we implicitly solve the heat equation with the variable diffusive coefficient and a source term. Then, in the second step, using a closed-form solution for the nonlinear equation, we get an analytic solution. We overcome the time step constraint associated with most numerical implementations of geometric active contours. We demonstrate performance of the proposed image segmentation algorithm on several artificial as well as real image examples.

Spatio-Angular Consistent Edit Propagation for 4D Light Field Image (4 차원 Light Field 영상에서의 일관된 각도-공간적 편집 전파)

  • Williem, Williem;Park, In Kyu
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2015.11a
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    • pp.180-181
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    • 2015
  • In this paper, we present a consistent and efficient edit propagation method that is applied for light field data. Unlike conventional sparse edit propagation, the coherency between light field sub-aperture images is fully considered by utilizing light field consistency in the optimization framework. Instead of directly solving the optimization function on all light field sub-aperture images, the proposed optimization framework performs sparse edit propagation in the extended focus image domain. The extended focus image is the representative image that contains implicit depth information and the well-focused region of all sub-aperture images. The edit results in the extended focus image are then propagated back to each light field sub-aperture image. Experimental results on test images captured by a Lytro off-the-shelf light field camera confirm that the proposed method provides robust and consistent results of edited light field sub-aperture images.

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Depth Extraction of Partially Occluded 3D Objects Using Axially Distributed Stereo Image Sensing

  • Lee, Min-Chul;Inoue, Kotaro;Konishi, Naoki;Lee, Joon-Jae
    • Journal of information and communication convergence engineering
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    • v.13 no.4
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    • pp.275-279
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    • 2015
  • There are several methods to record three dimensional (3D) information of objects such as lens array based integral imaging, synthetic aperture integral imaging (SAII), computer synthesized integral imaging (CSII), axially distributed image sensing (ADS), and axially distributed stereo image sensing (ADSS). ADSS method is capable of recording partially occluded 3D objects and reconstructing high-resolution slice plane images. In this paper, we present a computational method for depth extraction of partially occluded 3D objects using ADSS. In the proposed method, the high resolution elemental stereo image pairs are recorded by simply moving the stereo camera along the optical axis and the recorded elemental image pairs are used to reconstruct 3D slice images using the computational reconstruction algorithm. To extract depth information of partially occluded 3D object, we utilize the edge enhancement and simple block matching algorithm between two reconstructed slice image pair. To demonstrate the proposed method, we carry out the preliminary experiments and the results are presented.