• Title/Summary/Keyword: Image quality

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Statistical Image Quality Measure (통계적 영상 품질 측정)

  • Bae, Kyoung-Yul
    • Journal of Intelligence and Information Systems
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    • v.13 no.4
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    • pp.79-90
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    • 2007
  • The image quality measure is an important issue in the image processing. Several methods which measure the image quality have been proposed and these are based on the mathematical point of view. However, there is difference between the mathematicalmeasure and the measure based on the human visual system and a new measure has to be proposed because the final target of the image is a human visual system In this paper, a statistical image quality measure which is considered the human visual feature was suggested. The human visual system is using the global quality of the image and the local quality of the image and the local quality is more important to human visual system. In this paper, the image divided into several segments and the image qualities were calculated respectively. After then, the statistical method using scoring was applied to the image qualities. The result of the image quality measure was similar to the result of measure based on the human visual system.

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Development of Image Quality Measurement Method of Coronary Angiography Using Image Analysis Program (영상 분석 프로그램을 이용한 관상동맥 혈관 조영상의 화질 측정 방법 고안)

  • Seo, Young-Hyun;Song, Jong-Nam
    • Journal of the Korean Society of Radiology
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    • v.14 no.2
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    • pp.111-120
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    • 2020
  • Research should be actively conducted for the ability of X-ray equipment and Retrospective image analysis of X-ray equipment used in hospitals. Retrospective image analysis of X-ray machines, CT and MRI of radiology and medical equipment has been actively conducted. However, image quality measurement using angiography equipment of angiography room is mostly measured with phantom, and image quality measurement on image after being taken by actual patient is insufficient and researches on accurate image quality measurement method are remarkable. It is in short supply. Therefore, through this study, the researcher devised a method to measure the image quality of the acquired image after coronary angiography, and to provide a high quality image to the operator. The equipment and programs used were angiographic examination equipment (Axiom Artis Zee Ceiling) and Image J program. Subjects were images automatically saved in PACS program after coronary angiography.For image quality measurement, selected the AP Caudal 30° image that show the LCA vessel well and the LAO 30° image that show the RCA vessel well during the coronary angiography. In order to measure the background and ROI of the selected image by selecting an image, a criterion on how to find and measure a section where the overlap of the shadow, such as blood vessel, liver and lung is minimized, is presented. In conclusion, there is no exact standard for analyzing an image quality measurement method of angiography image. Therefore, in order to provide quality images to the practistioners, not only the technicians of the equipment but also the users who actually use them should become researchers and conduct research on image quality measurement in various ways. Thus, it is expected to provide excellent images to patients.

No-Reference Image Quality Assessment based on Quality Awareness Feature and Multi-task Training

  • Lai, Lijing;Chu, Jun;Leng, Lu
    • Journal of Multimedia Information System
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    • v.9 no.2
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    • pp.75-86
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    • 2022
  • The existing image quality assessment (IQA) datasets have a small number of samples. Some methods based on transfer learning or data augmentation cannot make good use of image quality-related features. A No Reference (NR)-IQA method based on multi-task training and quality awareness is proposed. First, single or multiple distortion types and levels are imposed on the original image, and different strategies are used to augment different types of distortion datasets. With the idea of weak supervision, we use the Full Reference (FR)-IQA methods to obtain the pseudo-score label of the generated image. Then, we combine the classification information of the distortion type, level, and the information of the image quality score. The ResNet50 network is trained in the pre-train stage on the augmented dataset to obtain more quality-aware pre-training weights. Finally, the fine-tuning stage training is performed on the target IQA dataset using the quality-aware weights to predicate the final prediction score. Various experiments designed on the synthetic distortions and authentic distortions datasets (LIVE, CSIQ, TID2013, LIVEC, KonIQ-10K) prove that the proposed method can utilize the image quality-related features better than the method using only single-task training. The extracted quality-aware features improve the accuracy of the model.

Emotional Image Quality Evaluation Technology for Display Devices

  • Lee, Eun-Jung;Lee, Seung-Bae
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.23 no.3
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    • pp.10-17
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    • 2009
  • In this paper, we explained the relation between evaluating display device and emotional image quality evaluation in human perceptual view. It is also suggested two emotional image quality evaluation method of display reflecting human visual function. One is the color space of CIECAM02 and the other is capturing moving image. It is necessary to standardize the evaluation methods of image quality based on emotional evaluation.

A Method of Stereoscopic 3D Image Quality Assessment (스테레오스코픽 3D영상 화질 평가 방법)

  • Park, Young-Soo;Hur, Nam-Ho;Pyo, Kyung-Soo;Song, Chung-Kun
    • Journal of Broadcast Engineering
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    • v.16 no.2
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    • pp.319-330
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    • 2011
  • For objective assessment of stereoscopic 3D image quality, we measure quality of left and right image with 2D image quality measurement method. However, this method is inconvenient because that we have to measure quality of left and right image individually. Therefore we propose a method of stereoscopic 3D image quality assessment using one overlaid image with left and right image. Using this method, One can measure quality of stereoscopic 3D image more easily and quickly.

Body Image and Quality of Life in Women with Mastectomy (유방절제술 환자의 신체상과 삶의 질의 관계)

  • Park, Geum-Ja;Choi, J.S.
    • Asian Oncology Nursing
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    • v.8 no.2
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    • pp.86-92
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    • 2008
  • Purpose: This study was designed to investigate the body-image and quality of life in breast cancer patients with mastectomy. Methods: Data were obtained by self-reported questionaries from 110 patients undergone mastectomy from August 1 to 31, 2007. And data were analyzed using SPSS/PC WIN 12.0 program and frequency, percentage, mean, minimum, maximum, t-test, ANOVA, Scheffe test, Pearson's Correlation Coefficient were used. The results of the study were as follows; 1) Mean of Body image of the subjects was $52.54{\pm}6.67$ (range of scale; 17 to 85). Mean of quality of life was $118.01{\pm}34.37$ (range of scale; 0 to 10). 2) There was no significant difference with the score of body image by demographic and disease-related characteristics of subjects. 3) There was significant difference with the score of quality of life by the work type and economic status of subjects. 4) Relationship between body image and quality of life showed moderately strong positive correlation (r=0.408, p<0.0001). Conclusion: Mean of body image and of quality of life in mastectomy patients were moderate. Relationship between body image and quality of life showed moderately strong positive correlation. Therefore, for improving the quality of life, it is needed to improve body image in breast cancer patients with mastectomy.

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No-reference Image Quality Assessment With A Gradient-induced Dictionary

  • Li, Leida;Wu, Dong;Wu, Jinjian;Qian, Jiansheng;Chen, Beijing
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.1
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    • pp.288-307
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    • 2016
  • Image distortions are typically characterized by degradations of structures. Dictionaries learned from natural images can capture the underlying structures in images, which are important for image quality assessment (IQA). This paper presents a general-purpose no-reference image quality metric using a GRadient-Induced Dictionary (GRID). A dictionary is first constructed based on gradients of natural images using K-means clustering. Then image features are extracted using the dictionary based on Euclidean-norm coding and max-pooling. A distortion classification model and several distortion-specific quality regression models are trained using the support vector machine (SVM) by combining image features with distortion types and subjective scores, respectively. To evaluate the quality of a test image, the distortion classification model is used to determine the probabilities that the image belongs to different kinds of distortions, while the regression models are used to predict the corresponding distortion-specific quality scores. Finally, an overall quality score is computed as the probability-weighted distortion-specific quality scores. The proposed metric can evaluate image quality accurately and efficiently using a small dictionary. The performance of the proposed method is verified on public image quality databases. Experimental results demonstrate that the proposed metric can generate quality scores highly consistent with human perception, and it outperforms the state-of-the-arts.

Correlation Research between Objective and Subjective Image Quality Assessment (객관적 화질 평가와 주관적 화질 평가의 상관관계 연구)

  • Park, Hyung-Ju;Har, Dong-Hwan
    • The Journal of the Korea Contents Association
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    • v.11 no.8
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    • pp.68-76
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    • 2011
  • Due to the high interests of image quality by consumers, the concerned market becomes more heated. Recent digital camera development tendency shows to perform the higher image quality to meet consumers demand of quality satisfaction. However it is hard to confirm that development of objective image quality performance means positive subjective image quality preference. And also, we cannot find out the previous researches concerned on correlation between objective and subjective image quality comparison. Therefore, it is necessary to analyze the consumers preferred images based on objective image quality performance. Throughout this paper, we analyze statistical correlation between the objective and subjective image quality assessment methods by using ISO standards. In these results, we try to find attributes that enhance image quality. We suggest not only to analyze and reflect on customers' preferences, but also to pursue the high quality image performance practically. We expect the results of this paper to positively influence product development.

A Study on the Improvement of the Image Quality for UAV Using Drift Compensation (편류보정을 통한 무인항공기 영상품질 향상에 관한 연구)

  • Lee, Mal-Young
    • Journal of Korean Society for Quality Management
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    • v.41 no.3
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    • pp.405-412
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    • 2013
  • Purpose: In this paper, the improvement of the image quality is investigated. The image quality is degraded by the drift phenomenon of EO/IR (Electro-Optical/Infrared) device on UAV. The drift phenomenon means that the image of EO/IR equipment on UAV(Unmanned Aerial Vehicle) moves to the unintended direction. This phenomenon should be improved for successful flight mission. Methods: To improve the drift phenomenon, the drift compensation method, the combination algorithm of FMC(Forward Motion Compensation) and AMC(Angular Motion Compensation) method, are introduced to calculate pitch and azimuth angle. Result values of pitch and azimuth angle are used for the improvement of image quality in EO/IR control logic. Results: The image quality is quantitatively improved more than 15 times through field test data of flight. Conclusion: Using the drift compensation technique, the image quality for EO/IR equipment is improved over 15 times than existing methods. This means the user of UAV with EO/IR device can perform a successful mission by keeping the line of sight for the target accurately.

The Linkages among Restaurant Image, Food and Beverage Price, Value and Service Quality (레스토랑 이미지, 식음료 가격, 가치와 서비스 품질과의 관계)

  • Kang, Jong-Heon;Ko, Beom-Seok
    • Journal of the East Asian Society of Dietary Life
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    • v.17 no.2
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    • pp.266-273
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    • 2007
  • The purpose of this study was to measure the effects of service quality mediating the linkage among food and beverage price, restaurant image and value. A total of 273 questionnaires were completed. MANOVA, ANOVA and ANCOVA were used to measure the mediating effect of service quality on the relationships among food and beverage price, restaurant image, and value. The effects of food and beverage price and restaurant image on service quality and value were statistically significant. As expected, when food and beverage price and service quality were regressed on the value, the service quality was significant and the effect of the food and beverage price was reduced. Moreover, when restaurant image and service quality were regressed on the value, the restaurant image and service quality had a significant effects on value. The results demonstrated that service quality played a mediating role in the relationship between food and beverage price and value, and between restaurant image and value.

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