• 제목/요약/키워드: Sharpness of Image

검색결과 152건 처리시간 0.024초

A Low Motion Blurring Algorithm on FPD systems

  • Yun, Jong-Ho;Kwon, Byong-Heon;Choi, Myung-Ryul
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.183-186
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    • 2003
  • We propose a new interpolation algorithm that can effectively decrease motion blurring on moving image. The proposed algorithm can be easily applied to FPD systems, since its structure is very simple. The proposed algorithm has been simulated and verified for image definition and sharpness, quantitatively and qualitatively. The simulation result shows that the proposed method provides better performance than the conventional ones..

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시각 선명도 감각 특성을 이용한 개선된 고명암 대비 영상 렌더링 기법 (Enhanced High Contrast Image Rendering Method Using Visual Properties for Sharpness Perception)

  • 이근영;이성학;권혁주;송규익
    • 한국통신학회논문지
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    • 제38A권8호
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    • pp.669-679
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    • 2013
  • HDR (high dynamic range) 영상을 LDR (low dynamic range) 영상으로 변환할 때 톤 맵핑 (tone mapping) 과정은 필수적이다. 많은 TMO (tone mapping operator)는 인간 시각 시스템의 특성들을 모방하여 발달되어 왔고 그 중 가장 대표적인 시각 특성이 국부 순응 방식이다. 그러나 TMO는 밝기나 명암, 채도 등의 영상 정보들을 압축하여 LDR 영상으로 대응시키기 때문에 압축에 의한 화질 저하가 나타난다. 본 논문에서는 TMO에 의한 화질 저하 보상을 위해 인간 시각의 선명도 특성을 기저 및 세부 영상 분할 처리에 적용하여 휘도 적응적 에지 보존 함수를 제안했다. 또한, 인간 시각 시스템에서 공간 주파수와 대비 민감도 사이의 관계를 나타내는 CSF (contrast sensitivity function)를 이용하여 선명화 필터를 설계하고, 이를 배경 휘도에 따라 적응적으로 적용하였다.

Effect of scattered x-rays on subject contrast and image sharpness

  • Arimura, Hidetaka;Date, Takuji;Morikawa, Kaoru;Kubota, Hideaki;Matsumoto, Masao;Kanamori, Hitoshi
    • 한국의학물리학회:학술대회논문집
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    • 한국의학물리학회 1999년도 Japanese Journal of Medical Physics
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    • pp.278-281
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    • 1999
  • The purpose of this study is to investigate the effect of the scattered x-rays on the subject contrast and image sharpness for various tube voltages. For the purpose, we measured the scatter-to-primary ratio(SPR) for the tube voltages f 50 to 100kV and obtained the tube voltage dependence of the subject contrast of an aluminum plate in a polymethyl methacrylate(PMMA) phantom. Furthermore, the overall modulation transfer functions(MTFs), which consist of MTFs of a screen-film system and scatter FTMs, were obtained for tube voltages of 50 to 100 kV. The subject contrast decreased with the tube voltage due to that the SPR increased with the tube voltage and that the difference in effective linear attenuation coefficients between the object and its surroundings decreased with the tube voltage. The maximum frequency of the overall MTF decreased from about 2 mm$\^$-1/ to 1 mm$\^$-1/ with the tube voltage increasing from 50 to 100 kV.

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Local Binary Pattern Based Defocus Blur Detection Using Adaptive Threshold

  • Mahmood, Muhammad Tariq;Choi, Young Kyu
    • 반도체디스플레이기술학회지
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    • 제19권3호
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    • pp.7-11
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    • 2020
  • Enormous methods have been proposed for the detection and segmentation of blur and non-blur regions of the images. Due to the limited available information about the blur type, scenario and the level of blurriness, detection and segmentation is a challenging task. Hence, the performance of the blur measure operators is an essential factor and needs improvement to attain perfection. In this paper, we propose an effective blur measure based on the local binary pattern (LBP) with the adaptive threshold for blur detection. The sharpness metric developed based on LBP uses a fixed threshold irrespective of the blur type and level which may not be suitable for images with large variations in imaging conditions and blur type and level. Contradictory, the proposed measure uses an adaptive threshold for each image based on the image and the blur properties to generate an improved sharpness metric. The adaptive threshold is computed based on the model learned through the support vector machine (SVM). The performance of the proposed method is evaluated using a well-known dataset and compared with five state-of-the-art methods. The comparative analysis reveals that the proposed method performs significantly better qualitatively and quantitatively against all the methods.

SPECKLE IMAGING TECHNIQUE FOR LUNAR SURFACES

  • Kim, Jinkyu;Sim, Chae Kyung;Jeong, Minsup;Moon, Hong-Kyu;Choi, Young-Jun;Kim, Sungsoo S.;Jin, Ho
    • 천문학회지
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    • 제55권4호
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    • pp.87-97
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    • 2022
  • Polarimetric measurements of the lunar surface from lunar orbit soon will be available via Wide-Field Polarimetric Camera (PolCam) onboard the Korea Pathfinder Lunar Orbiter (KPLO), which is planned to be launched in mid 2022. To provide calibration data for the PolCam, we are conducting speckle polarimetric measurements of the nearside of the Moon from the Earth's ground. It appears that speckle imaging of the Moon for scientific purposes has not been attempted before, and there is need for a procedure to create a "lucky image" from a number of observed speckle images. As a first step of obtaining calibration data for the PolCam from the ground, we search for the best sharpness measure for lunar surfaces. We then calculate the minimum number of speckle images and the number of images to be shift-and-added for higher resolution (sharpness) and signal-to-noise ratio.

모바일 로봇을 위한 Ekf이미지 안정화 시스템 개발 (The Development Of An Image Stabilization System Using An Extended Kalman Filter Used In A Mobile Robot)

  • 최윤원;;강태훈;이석규
    • 로봇학회논문지
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    • 제5권4호
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    • pp.367-376
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    • 2010
  • This Paper Proposes A Robust Image Stabilization System For A Mobile Robot Using An Extended Kalman Filter (Ekf). Though Image Information Is One Of The Most Efficient Data Used For Robot Navigation, It Is Subjected To Noise Which Is The Result Of Internal Vibration As Well As External Factors Such As Uneven Terrain, Stairs, Or Marshy Surfaces. The Camera Vibration Deteriorates The Image Resolution By Destroying The Image Sharpness, Which Seriously Prevents Mobile Robots From Recognizing Their Environment For Navigation. In This Paper, An Inclinometer Was Used To Measure The Vibration Angle Of The Camera System Mounted On The Robot To Obtain A Reliable Image By Compensating For The Angle Of The Camera Vibration. In Addition The Angle Prediction Obtained By Using The Ekf Enhances The Image Response Analysis For Real Time Performance. The Experimental Results Show The Effectiveness Of The Proposed System Used To Compensate For The Blurring Of The Images.

A Study of Property on Trilateral Elevation in the Acute Angle Site

  • CHO, JAE-HEE
    • International Journal of Advanced Culture Technology
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    • 제9권1호
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    • pp.22-27
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    • 2021
  • Morphology of contemporary city streets is composed of overlapping infrastructures corresponding to the new street within the established organization, contemporary system, future circumstance, and population. As well, two overlaid organizations and morphological, historical, social and physical development lead to sharp acute algle(triangular) site, and the architecture in this site has a restriction on the availability of the internal space and the external design due to outside shape sharpness. We want to have a positive effect on the internal and external design of the architecture in the future by categorization of the shape and processing characteristics of the acute angle corner of the trilateral site. The characteristics and design categorization shown in this case study are as follows. Constitution a unique and independent form, lead streets and shape a exclusive image of the landscape, alleviate sharpness by configuring a acute angle point as a plane, use void to give reserve character, replace roundness for companionability to induce ambience in the road, embrace the characteristics of the site and create internal spaces and functions, emphasize the characteristics of each stairs, retain of uniqueness and highlight the characteristics of a vertical elements.

Multi-Focus Image Fusion Using Transformation Techniques: A Comparative Analysis

  • Ali Alferaidi
    • International Journal of Computer Science & Network Security
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    • 제23권4호
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    • pp.39-47
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    • 2023
  • This study compares various transformation techniques for multifocus image fusion. Multi-focus image fusion is a procedure of merging multiple images captured at unalike focus distances to produce a single composite image with improved sharpness and clarity. In this research, the purpose is to compare different popular frequency domain approaches for multi-focus image fusion, such as Discrete Wavelet Transforms (DWT), Stationary Wavelet Transforms (SWT), DCT-based Laplacian Pyramid (DCT-LP), Discrete Cosine Harmonic Wavelet Transform (DC-HWT), and Dual-Tree Complex Wavelet Transform (DT-CWT). The objective is to increase the understanding of these transformation techniques and how they can be utilized in conjunction with one another. The analysis will evaluate the 10 most crucial parameters and highlight the unique features of each method. The results will help determine which transformation technique is the best for multi-focus image fusion applications. Based on the visual and statistical analysis, it is suggested that the DCT-LP is the most appropriate technique, but the results also provide valuable insights into choosing the right approach.

영상의 화질 개선을 위한 Multi-Scale Retinex 기반의 적응적 언샤프 마스킹 필터 설계 (Adaptive Unsharp Masking Filter Design Based on Multi-Scale Retinex for Image Enhancement)

  • 김주영;김진헌
    • 한국멀티미디어학회논문지
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    • 제21권2호
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    • pp.108-116
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    • 2018
  • In this paper, we propose an image enhancement method based on Multi-Scale Retinex theory that designs Unsharp Masking Filter (UMF) and emphasizes the contrast ratio adaptively. Unsharp Masking (UM) technique emphasizes image sharpness and improves contrast ratio by adding high frequency component to the original image. The high frequency component is obtained by differentiating between original image and low frequency image. In this paper, we present how to design an UMF kernel and to adaptively apply it to increase the contrast ratio according to multi-scale retinex theory which resembles human visual system. Experimental results show that the proposed method has better quantitative performance indexes such as PSNR, ambe & SSIM and better qualitative feature like halo artifact suppression.

Perceptual Fusion of Infrared and Visible Image through Variational Multiscale with Guide Filtering

  • Feng, Xin;Hu, Kaiqun
    • Journal of Information Processing Systems
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    • 제15권6호
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    • pp.1296-1305
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    • 2019
  • To solve the problem of poor noise suppression capability and frequent loss of edge contour and detailed information in current fusion methods, an infrared and visible light image fusion method based on variational multiscale decomposition is proposed. Firstly, the fused images are separately processed through variational multiscale decomposition to obtain texture components and structural components. The method of guided filter is used to carry out the fusion of the texture components of the fused image. In the structural component fusion, a method is proposed to measure the fused weights with phase consistency, sharpness, and brightness comprehensive information. Finally, the texture components of the two images are fused. The structure components are added to obtain the final fused image. The experimental results show that the proposed method displays very good noise robustness, and it also helps realize better fusion quality.