• 제목/요약/키워드: Evaluation of image quality

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A Trade-off Image Fusion Technique Using Fast Intensity-Hue-Saturation Transform (Fast IHS 변환을 이용한 trade-off 영상 융합기법)

  • Kim, Yong-Hyun;Kim, Youn-Soo
    • Aerospace Engineering and Technology
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    • v.8 no.2
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    • pp.26-32
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    • 2009
  • In the satellite image fusion, the most important point is to preserve both the spatial detail of panchromatic(PAN) image and the spectral information of multispectral(MS) image. Among various image fusion techniques, fusion technique using Intensity-Hue-Saturation(IHS) transform is widely used and it has advantage that computation is very simple. In this study, a fusion technique using fast IHS transform and trade-off parameter $\alpha^i$ proposed. Proposed fusion technique permits customization of the trade-off between the spectral information and spatial detail quality of the fused image through the evaluation of two quality indices: a spectral index(the spectral ERGAS) and a spatial one(the spatial ERGAS). Based on the result of experiment using IKONOS image, we confirmed the proposed fusion technique was more effective in preserving spatial detail and spectral information than existing fusion techniques using fast IHS transform.

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Dose and Image Assessment according to Radiologic Factors Variation at Digital Humerus X-ray Examination (디지털 환경에서 Humerus 검사 시 촬영인자 변화에 따른 선량 및 화질 평가)

  • Kim, Seong Min;Hong, Seon Sook;Lee, Kwan Sup;Ha, Dong Yun
    • Korean Journal of Digital Imaging in Medicine
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    • v.14 no.2
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    • pp.1-8
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    • 2012
  • Purpose : We aim at presenting the optimum radiologic factor through the evaluation of dose variation and of image quality through the use of a grid in Humerus examination and the change of dose because of the change of radiologic factor. Materials and Methods : We divided it in 3 cases: when using a grid or not and when using IP(Image Plate) in a digital system. Also, as fixing kVp to 70kVp it changed mAs, and fixing mAs to 10 it changed kVp, we put up resolution chart and Burger rose phantom on the acrylic phantom of 7cm (the same level of Humerus) to evaluate the dose and image. We used Image J program to evaluate the quantitative resolution of the obtained image, and made the qualitative evaluation and statistical analysis of the image saved in PACS for 20 radiologic technologist with more than 10 years of experience in order of evaluate its contrast. We used SPSS10(SPSS Inc. Chicago, Illinois) for statistical analysis. Results : We observed the analytic result of resolution by the change of kVp that it was $4.539dGycm^2$ in 60kVp and $757.472dGycm^2$ in 75kVp, which increased about 64.6% of dose, while for the resolution it had the pixel value 30.7% better with 851 in 60kVp than 651 in 75kVp. Also, we analyzed the result of resolution by the change of mAs that it was $3.106dGycm^2$ in 5mAs, and $12.470dGycm^2$ in 20mAs, which increased about 400% of dose, while for the resolution DR had 678 in 5mAs, and 724 in 20mAs that increased about 6.8% of resolution. We made the qualitative evaluation of contrast by the change of kVp that DR showed the higher quality than CR, but the contrast by the change of kVp had no special different at the moment of visual evaluation, nor statistically significant difference(P>0.05). We observed the qualitative evaluation of contraste by the change of mAs that the contrast increased as DR increased mAs, and had statistically significant difference(P<0.05). On the other hand, CR had no significant difference for more than 10mAs nor statistically significant difference(P>0.05). Conclusion : In case of some patients with radiographic exposure by the repeated examination such as emergent patient or Follow up patient, they are considered to try to limit the use of a grid, to set kVp under 65kVp in fixed mode, to select less than 10mAs and to reduce the possibility of patient being bombed.

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Dose and Image Evaluation of Pediatric Head Image according to CT Scan Mode and kVp Changes (CT Scan Mode와 관전압 변경에 따른 소아 두부 영상의 선량 및 영상평가)

  • Byeong-Je Kim;Dong-Hyun Kim
    • Journal of the Korean Society of Radiology
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    • v.17 no.6
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    • pp.801-808
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    • 2023
  • In order to minimize radiation exposure and secure diagnostic value images during CT examination of the head of children, the usefulness of volume axial mode is evaluated through comparison and analysis of exposure dose and images of volume axial mode, high pitch mode, and helical mode. Image evaluation and dose evaluation were performed in CT high pitch mode, helical mode, and volume axial mode for infants under the age of 1 according to the voltages of 70, 80, and 100 kVp tubes. The image evaluation was conducted by comparing image quality by setting ROI for each image, calculating SNR and CNR, using ONE-WAY (ANOVA) to evaluated statistical significance, and cross-examining the dose evaluation using DLP values displayed in the Dose Report. When inspected using volume axial mode, DLP values were generally low, and SNR and CNR values differed by ROI and kVp. When volume axial mode evaluated the quality of the image compared to other scan modes, the difference is not uniform. For the reason, certain modes are not considered excellent, but the exposure dose was reduced the most in terms of dose. In addition, the point that the volume axial mode can be examined at its original location, short scanning time and needless of table movement is useful for CT tests for children under 1 year of age with high radiation sensitivity.

Methodology on measuring the quality of service in telecommunications (통신에 있어서 서비스품질 측정방법)

  • 이영환;권세혁
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.33A no.10
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    • pp.28-39
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    • 1996
  • The methodology is suggested to measure the quality of service in telecommunications. Through questionnaire, the subjective evaluation of users is surveyed, and quantified by MOS method. The MOS mehtod has some problems in interpretation which are mentioned in this paper. The cumulative percent curve is proposed to evaluate the quality of service. As an example, the image quality of G3 facsimile is measured.

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Quantitative Analysis of Landscape in Tokyusan National Park (덕유산 국립공원 경관에 대한 계량적 분석)

  • 김세천
    • Korean Journal of Environment and Ecology
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    • v.7 no.2
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    • pp.231-240
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    • 1994
  • The purpose of this study is to suggest the objective basic data for applying to development and conservation management of the national park through the quantitative analysis of the visual quality included in the and physical environment of the Tokyusan National Park. For this, spatial images and structures, of natural elements have been analyzed by factor analysis algorithm, and degree of visual quality has been measured mainly through questionnaries. Result of this study can be summarized as follows. Factors covering the spatial image of the Tokyusan National Park landscape have been found to be the overall synthetic evaluation, appeal, spatial, natural quality and dignity factors such as the overall synthetic evaluation, spatial and appeal yield high factor scores. The main factors determining the degree of visual quality are the clearness valley, peculiarity of configuration, natural of trail, harmony of suitable artificial planting and temple.

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Quantitative Evaluation Method for Etch Sidewall Profile of Through-Silicon Vias (TSVs)

  • Son, Seung-Nam;Hong, Sang Jeen
    • ETRI Journal
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    • v.36 no.4
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    • pp.617-624
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    • 2014
  • Through-silicon via (TSV) technology provides much of the benefits seen in advanced packaging, such as three-dimensional integrated circuits and 3D packaging, with shorter interconnection paths for homo- and heterogeneous device integration. In TSV, a destructive cross-sectional analysis of an image from a scanning electron microscope is the most frequently used method for quality control purposes. We propose a quantitative evaluation method for TSV etch profiles whereby we consider sidewall angle, curvature profile, undercut, and scallop. A weighted sum of the four evaluated parameters, nominally total score (TS), is suggested for the numerical evaluation of an individual TSV profile. Uniformity, defined by the ratio of the standard deviation and average of the parameters that comprise TS, is suggested for the evaluation of wafer-to-wafer variation in volume manufacturing.

Evaluation of the Noise Power Spectrum by Using American College of Radiology Phantom for Magnetic Resonance Imaging (자기공명영상에서 ACR 팬텀을 이용한 잡음전력스펙트럼 평가)

  • Jung-Whan Min;Hoi-Woun Jeong
    • Journal of radiological science and technology
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    • v.47 no.1
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    • pp.21-28
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    • 2024
  • This study was purpose to quantitative evaluation of comparison of the image intensity uniformity and noise power spectrum (NPS) by using American college of radiology (ACR) phantom for magnetic resonance imaging (MRI). The MRI was used achiva 3.0T MRI and discovery MR 750, 3.0T, the head and neck matrix shim SENSE head coil were 32 channels receive MR coil. The MRI was used parameters of image sequence for ACR standard and general hospital. NPS value of the ACR standard T2 vertical image in GE equipment was 7.65E-06 when the frequency was 1.0 mm-1. And the NPS value of the ACR hospital T1 region of interest (ROI) 9 over all vertical image in Philips equipment was 9E-08 when the frequency was 1.0 mm-1 and the NPS value of the hospital T2 ROI 9 over all vertical image in Philips equipment was 1.06E-07 when the frequency was 1.0 mm-1. NPS was used efficiently by using a general hospital vertical sequence more than the standard vertical sequence method by using the ACR phantom. Furthermore NPS was the quantitative quality assurance (QA) assessment method for noise and image intensity uniformity characteristics was applied mutatis mutandis, and the results values of the physical imaging NPS of the 3.0T MRI and ACR phantom were presented.

Development of On-line Quality Sorting System for Dried Oak Mushroom - 3rd Prototype-

  • 김철수;김기동;조기현;이정택;김진현
    • Agricultural and Biosystems Engineering
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    • v.4 no.1
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    • pp.8-15
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    • 2003
  • In Korea, quality evaluation of dried oak mushrooms are done first by classifying them into more than 10 different categories based on the state of opening of the cap, surface pattern, and colors. And mushrooms of each category are further classified into 3 or 4 groups based on its shape and size, resulting into total 30 to 40 different grades. Quality evaluation and sorting based on the external visual features are usually done manually. Since visual features of mushroom affecting quality grades are distributed over the entire surface of the mushroom, both front (cap) and back (stem and gill) surfaces should be inspected thoroughly. In fact, it is almost impossible for human to inspect every mushroom, especially when they are fed continuously via conveyor. In this paper, considering real time on-line system implementation, image processing algorithms utilizing artificial neural network have been developed for the quality grading of a mushroom. The neural network based image processing utilized the raw gray value image of fed mushrooms captured by the camera without any complex image processing such as feature enhancement and extraction to identify the feeding state and to grade the quality of a mushroom. Developed algorithms were implemented to the prototype on-line grading and sorting system. The prototype was developed to simplify the system requirement and the overall mechanism. The system was composed of automatic devices for mushroom feeding and handling, a set of computer vision system with lighting chamber, one chip microprocessor based controller, and pneumatic actuators. The proposed grading scheme was tested using the prototype. Network training for the feeding state recognition and grading was done using static images. 200 samples (20 grade levels and 10 per each grade) were used for training. 300 samples (20 grade levels and 15 per each grade) were used to validate the trained network. By changing orientation of each sample, 600 data sets were made for the test and the trained network showed around 91 % of the grading accuracy. Though image processing itself required approximately less than 0.3 second depending on a mushroom, because of the actuating device and control response, average 0.6 to 0.7 second was required for grading and sorting of a mushroom resulting into the processing capability of 5,000/hr to 6,000/hr.

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360° Projection Image Analysis Method for the Calibration (보정을 위한 고해상도 360° 프로젝션 영상 분석 방법)

  • Han, Jung-Soo;Kim, Gui-Jung
    • Journal of Digital Convergence
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    • v.13 no.12
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    • pp.203-208
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    • 2015
  • Image degradation will occur depending on hardware characteristics according to the lapse of time between beam projectors when multivision system is installed in the Theme park/Exhibition/Science Museum. In this paper, we have researched the 10-bit High-depth and high-resolution $360^{\circ}$ projection image analysis technique to solve the problems of quality and the maintenance of the theater. The goal is to minimize the economic losses and the development of special theater calibration system that can efficiently support a quality of an image. We proposed the method of image analysis technology, and explained the detailed functions and evaluation methods for image analysis technique. Evaluation method included the performance items, and proposed reasonable value to the experimental method and the goal value.

A Study on the Positioning of Brand Image of Ready-made Lady Wear (여성기성복 상표이미지의 포지셔닝에 관한 연구)

  • Kim Hae Jung;Lim Sook Ja
    • Journal of the Korean Society of Clothing and Textiles
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    • v.16 no.2
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    • pp.263-275
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    • 1992
  • This study intends to provide strategic positioning of brand image analysed from the view point of perceptual dimensions of clothing consumers. Consumers are segmented on the basis of the attributes of brand image, and in each segment, perceptual map is composed according to multidimensional scaling. The results are as follows; 1. According to the Benefit Segmentation, it is statistically significant that the consumers are divided into 'product-factor oriented group 'and' image-factor oriented group'. 2. From the analysis of perceptual map upon the 'similarity of brand image,'image-factor oriented group 'perceives more differently than 'product-factor oriented group' 3. From the analysis of perceptual map with the evaluation of attributes of brand image, price, promotion and design are significant determinants in 'total consumer group'. In addition, store image is significant determinant in' image-factor oriented group' and quality is significant determinant in' product-factor oriented group'. According to the evaluation of consumers on 8 brands with determining attribute-vector, ranks of brands in each segment are similar in the vector of price and promotion but different in the vector of design between segment groups. 4. From the analysis of perceptual map upon the preference of brand image, the distribution of preference and position of ideal point are different between segment groups. 5. With evaluation of purchase habit, statistically significant differences are found between groups segmented in the degree of importance of attributes, purchasing motive, purchasing time, sources of information and expenses for clothes.

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