• Title/Summary/Keyword: Image Clarity

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A Study on the Image Evaluation of Buildings in the University Campus (대학캠퍼스 건축물에 대한 이미지평가에 관한 연구)

  • Kim, Cheon-Il;Kim, Ick-Hwan
    • Journal of the Korean Institute of Educational Facilities
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    • v.19 no.3
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    • pp.13-20
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    • 2012
  • In this study, we performed the psychological analysis on campus facilities for university students with the observation that the evaluation on the physical environment of the campus is related to the image evaluation of the campus users. Specifically, we investigated the cognitive structure and the image evaluation structure of users, i.e., students, on the architectural and morphological elements of campus buildings. The investigation results are summarized as follows. 1) The cognitive structure of students on the architectural and morphological elements was different from building to building. In the case of architectural elements, the campus buildings were rated high, if they were designed with emphasis on symbolic elements, while the campus buildings with simple design were rated low. However, the morphological elements exhibited the opposite results. 2) We extracted six factors by performing the factor analysis for image evaluation. From the analysis results, we found that students showed a different structure of image evaluation for each building. In addition, the image evaluation structures were found to be related with the cognitive structures on architectural and morphological elements. 3) We also performed the correlation analysis between image evaluation structure and cognitive structure on architectural and morphological aspects. The analysis results indicated that each building showed different correlation patterns. In addition, the overall image became better, as they appraised "clarity" and "uniformity" more highly.

Image Matching Based on Robust Feature Extraction for Remote Sensing Haze Images (위성 안개 영상을 위한 강인한 특징점 검출 기반의 영상 정합)

  • Kwon, Oh-Seol
    • Journal of Broadcast Engineering
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    • v.21 no.2
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    • pp.272-275
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    • 2016
  • This paper presents a method of single image dehazing and surface-based feature detection for remote sensing images. In the conventional dark channel prior (DCP) algorithm, the resulting transmission map invariably includes some block artifacts because of patch-based processing. This also causes image blur. Therefore, a refined transmission map based on a hidden Markov random field and expectation-maximization algorithm can reduce the block artifacts and also increase the image clarity. Also, the proposed algorithm enhances the accuracy of image matching surface-based features in an remote sensing image. Experimental results confirm that the proposed algorithm is superior to conventional algorithms in image haze removal. Moreover, the proposed algorithm is suitable for the problem of image matching based on feature extraction.

Extraction of UAV Image Sharpness Index Using Edge Target Analysis (에지 타겟 분석을 통한 무인기 영상의 선명도 지표 추출)

  • Lim, Pyung-Chae;Seo, Junghoon;Kim, Taejung
    • Korean Journal of Remote Sensing
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    • v.34 no.6_1
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    • pp.905-923
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    • 2018
  • In order to generate high-resolution products using UAV images, it is necessary to analyze the sharpness of the themselves measured through image analysis. When images that have unclear sharpness of UAV are used in the production, they can have a great influence on operations such as acquisition and mapping of accurate three-dimensional information using UAV. GRD (Ground Resolved Distance) has been used as an indicator of image clarity. GRD is defined as the minimum distance between two identifiable objects in an image and is used as a concept against the GSD (Ground Sampling Distance), which is a spatial sample interval. In this study, GRD is extracted by analyzing the edge target without visual analysis. In particular, GRD to GSD ratio (GRD/GSD), or GRD expressed in pixels, is used as an index for evaluation the relative image sharpness. In this paper, GRD is calculated by analyzing edge targets at various altitudes in various shooting environments using a rotary wing. Using GRD/GSD, it was possible to identify images whose sharpness was significantly lowered, and the appropriateness of the image as an image clarity index was confirmed.

Improvement of Dynamic Characteristics of OIS System using Improved Band Notch and Analysis of Images (노치 대역을 개선한 이미지 흔들림 보정 장치의 동특성 향상과 이미지 분석)

  • Son, Dong-Hun;Park, No-Cheol;Park, Young-Pil;Park, Kyoung-Su
    • Transactions of the Society of Information Storage Systems
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    • v.7 no.2
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    • pp.70-74
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    • 2011
  • The mobile camera module is a device to be inserted in the digital device for camera feature. The mobile camera module is being shaken by vibrations such as handshake during the exposure time. The clarity is compromised by these vibrations, thus the vibration is considered as an external disturbance. Moreover the use of mobile camera module has been being expanded for automotive vibration should be considered. These external disturbances can cause image blurring, thus optical image stabilization should be applied for image compensation. The compensator is fulfilled mechanically by movable lens group or image sensor that adjusts the optical path to the camera movement. Open loop control is useful for well-defined systems like compliant mechanism. Notch filter and lead compensator are designed and applied to improve the stability and bandwidth. The final level of image compensating is confirmed by image processing with MATLAB and CODE V to verify the better performance.

EVALUATION OF MANDIBULAR CONDYLE POSITION IN TMJ TRANSCRANIAL RADIOGRAPH (악관절의 경두개 방사선사진에서 하악과두위 평가에 관한 연구)

  • Do Jeong-ju;Kim Eun-Kyung
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.22 no.1
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    • pp.67-75
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    • 1992
  • Transcranial radiograph is widely used in the diagnosis of craniomandibular disorder because it can be used by the dentist with relative ease in spite of image distortion. But correct information can be obtained only when one know the image change by projection angulation. The author compared the condyle position in the 3 groups of transcranial radiographs (horizontal angulation - 0°, 5°, individualized) with that in the individualized corrected lateral tomogram by objective and subjective evaluation methods. The results were as follows: 1. Among 3 transcranial groups, the condyle position in individualized group showed the highest concordance rate with that in the tomogram group in objective and subjective evaluation methods. 2. Correlation coefficient between individualized transcranial group and tomogram group in objective evaluation method was highest (P≤0.01). 3. Image clarity in individualized transcranial group was worse than that of the other two transcranial groups.

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Fingerprint Identification System Using Ridge Direction Extraction by Index Table (Index table에 의한 융선의 방향성 추출을 이용한 지문 인식 시스템)

  • Lee, Jee-Won;Ahn, Do-Rang;Lee, Dong-Wook
    • Proceedings of the KIEE Conference
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    • 2005.10b
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    • pp.180-182
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    • 2005
  • Fingerprint-based identification is known to be used for a very long time. Owing to their uniqueness and immutability, fingerprints are today the most widely used biometric features. Therefore, recognition using fingerprints is one of the safest methods as a way of personal identification. But fingerprint identification system has a critical weakness. Since the fingerprint identification time dramatically increase when we compare the unknown fingerprint's minutiae with fingerprint database's minutiae. In this paper, a ridge orientation extraction method using Index table is proposed to solve the problem. The goal of fast direction image extraction is to reduce the identification time and to improve the clarity of ridge and valley structures of input fingerprint image.

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A Novel Multifocus Image Fusion Algorithm Based on Nonsubsampled Contourlet Transform

  • Liu, Cuiyin;Cheng, Peng;Chen, Shu-Qing;Wang, Cuiwei;Xiang, Fenghong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.3
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    • pp.539-557
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    • 2013
  • A novel multifocus image fusion algorithm based on NSCT is proposed in this paper. In order to not only attain the image focusing properties and more visual information in the fused image, but also sensitive to the human visual perception, a local multidirection variance (LEOV) fusion rule is proposed for lowpass subband coefficient. In order to introduce more visual saliency, a modified local contrast is defined. In addition, according to the feature of distribution of highpass subband coefficients, a direction vector is proposed to constrain the modified local contrast and construct the new fusion rule for highpass subband coefficients selection The NSCT is a flexible multiscale, multidirection, and shift-invariant tool for image decomposition, which can be implemented via the atrous algorithm. The proposed fusion algorithm based on NSCT not only can prevent artifacts and erroneous from introducing into the fused image, but also can eliminate 'block effect' and 'frequency aliasing' phenomenon. Experimental results show that the proposed method achieved better fusion results than wavelet-based and CT-based fusion method in contrast and clarity.

Template Mask based Parking Car Slots Detection in Aerial Images

  • Wirabudi, Andri Agustav;Han, Heeji;Bang, Junho;Choi, Haechul
    • Journal of Broadcast Engineering
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    • v.27 no.7
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    • pp.999-1010
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    • 2022
  • The increase in vehicle purchases worldwide is having a very significant impact on the availability of parking spaces. In particular, since it is difficult to secure a parking space in an urban area, it may be of great help to the driver to check vehicle parking information in advance. However, the current parking lot information is still operated semi-manually, such as notifications. Therefore, in this study, we propose a system for detecting a parking space using a relatively simple image processing method based on an image taken from the sky and evaluate its performance. The proposed method first converts the captured RGB image into a black-and-white binary image. This is to simplify the calculation for detection using discrete information. Next, a morphological operation is applied to increase the clarity of the binary image, and a template mask in the form of a bounding box indicating a parking space is applied to check the parking state. Twelve image samples and 2181 total of test, were used for the experiment, and a threshold of 40% was used to detect each parking space. The experimental results showed that information on the availability of parking spaces for parking users was provided with an accuracy of 95%. Although the number of experimental images is somewhat insufficient to address the generality of accuracy, it is possible to confirm the possibility of parking space detection with a simple image processing method.

A Novel Automatic Block-based Multi-focus Image Fusion via Genetic Algorithm

  • Yang, Yong;Zheng, Wenjuan;Huang, Shuying
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.7
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    • pp.1671-1689
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    • 2013
  • The key issue of block-based multi-focus image fusion is to determine the size of the sub-block because different sizes of the sub-block will lead to different fusion effects. To solve this problem, this paper presents a novel genetic algorithm (GA) based multi-focus image fusion method, in which the block size can be automatically found. In our method, the Sum-modified-Laplacian (SML) is selected as an evaluation criterion to measure the clarity of the image sub-block, and the edge information retention is employed to calculate the fitness of each individual. Then, through the selection, crossover and mutation procedures of the GA, we can obtain the optimal solution for the sub-block, which is finally used to fuse the images. Experimental results show that the proposed method outperforms the traditional methods, including the average, gradient pyramid, discrete wavelet transform (DWT), shift invariant DWT (SIDWT) and two existing GA-based methods in terms of both the visual subjective evaluation and the objective evaluation.

Adaptive High-order Variation De-noising Method for Edge Detection with Wavelet Coefficients

  • Chenghua Liu;Anhong Wang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.2
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    • pp.412-434
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    • 2023
  • This study discusses the high-order diffusion method in the wavelet domain. It aims to improve the edge protection capability of the high-order diffusion method using wavelet coefficients that can reflect image information. During the first step of the proposed diffusion method, the wavelet packet decomposition is a more refined decomposition method that can extract the texture and structure information of the image at different resolution levels. The high-frequency wavelet coefficients are then used to construct the edge detection function. Subsequently, because accurate wavelet coefficients can more accurately reflect the edges and details of the image information, by introducing the idea of state weight, a scheme for recovering wavelet coefficients is proposed. Finally, the edge detection function is constructed by the module of the wavelet coefficients to guide high-order diffusion, the denoised image is obtained. The experimental results showed that the method presented in this study improves the denoising ability of the high-order diffusion model, and the edge protection index (SSIM) outperforms the main methods, including the block matching and 3D collaborative filtering (BM3D) and the deep learning-based image processing methods. For images with rich textural details, the present method improves the clarity of the obtained images and the completeness of the edges, demonstrating its advantages in denoising and edge protection.