• Title/Summary/Keyword: Image comparison

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Distance Measurement Based on Structured Light Image for Mobile Robots (이동로봇을 위한 구조광 영상기반 거리측정)

  • Yi, Soo-Yeong;Hong, Young-Jin;Suh, Jin-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.16 no.1
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    • pp.18-24
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    • 2010
  • In this paper, we address an active ranging system based on laser structured light image for mobile robot application. Since the burdensome correspondence problem is avoidable, the structured light image processing has efficient computation in comparison with the conventional stereo image processing. By using a cylindrical lens in the laser generation, it is possible to convert a point laser into a stripe laser without motorized scan in the proposed system. In order to achieve robustness against environmental illumination noise, we propose an efficient integro-differential image processing algorithm. The proposed system has embedded image processing module and transmits distance data to reduce the computational burden in main control system.

Product image evaluation technique using fuzzy-weighted checklist (모호가중점검목록을 이용한 제품의 감성파악)

  • 박경수;정광태
    • Journal of the Ergonomics Society of Korea
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    • v.15 no.1
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    • pp.15-26
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    • 1996
  • When a product is designed, it is important to consider its image on consumers. In this study, we developed a technique to measure product image. Because human image of a product is very subjective and fuzzy, it is difficult to measure easily. To deal with this difficulty effectively, we used fuzzy- weighted checklist. The fuzzy-weighted checklist presents a fuzzy version of the weighted checklist technique for evaluating or comparing complex systems or subjects. In this technique, we used a pairwise comparison method to obtain the relative importance weights of image factors. Also, we used linguistic ratings to obtain the scores of image factors for a product. Then, we synthesized the scores of image factors to obtain a fuzzy composite score and its linguistic approximation. The entire procedure of this technique was written in quick Basic. As an example, this techinque is applied to car evaluation. The results show that this technique can be effectively used to the quqntitative evaluation of huamn image.

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The Preoperative Diagnosis of Thyroid Cancer in $^{18}F$-FDG PET/CT Dual Time Imaging of SUV and Evaluation of Radioactivity Measurement (갑상선암 수술 전 진단목적의 $^{18}F$-FDG PET/CT Dual Time Point영상에서 SUV값과 방사능 농도 측정법의 유용성 평가)

  • Lee, Hyun-Kuk;Khang, Hyun Soo;Yang, Seoung-Oh;Han, Man-Seok
    • The Korean Journal of Nuclear Medicine Technology
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    • v.16 no.2
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    • pp.99-105
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    • 2012
  • Purpose : This study is designed to compare two parameters reflecting $^{18}F$-FDG uptake, SUV and radioactivity, for diagnosis of thyroid cancer in dual time $^{18}F$-FDG PET/CT imaging and to find which parameter is more useful to decide whether the tumor is malignant or not. Materials and Methods : We performed retrospective study for 40 patients. All patients are diagnosed as primary thyroid cancer and examined $^{18}F$-FDG PET/CT. First, we got the dispersion of scattering beam of neck and lung apex to set a background and compared each dispersion, mean value, standard deviation of maxSUV and radioactivity. Also, mean maxSUV, ${\Delta}maxSUV$, ${\Delta}maxBq$/ml(%) and radioactivity between groups according to lesion's size based on biopsy are compared with independent-sample t-test. Results : the values that were from maxSUV and radioactivity measurement technique were compensated and calculated to practical values for mean comparison and patients were divided to two groups based on tumor size, Group1 ($size{\leq}1$ cm, n=21), Group2 (size>1 cm, n=19) for accurate comparison. In Group1, maxSUV (semi-quantitative analysis) was increased from $5.64{\pm}5.85$ (1.89~17.84) at first image to $5.90{\pm}5.01$ (1.95~18.22) at second image and radioactivity (Bq/ml) (quantitative analysis) showed similar increase from $5.93{\pm}6.38$ (2.50~16.75) at first image to $6.01{\pm}5.25$ (2.66~16.58) at second image. In Group2, TFmaxSUV was $10.54{\pm}14.36$ (2.54~33.89) in true first image, TSmaxSUV was $9.85{\pm}12.88$ (2.62~26.20) in true second image separately. The maxSUV showed a significant difference in the mean comparison between the two groups (p=0.035) But, mean radioactivity (Bq/ml) was $5.93{\pm}6.38$ (4.81~40.99) in true first image, $6.01{\pm}5.25$ (4.51~36.93) in true second image and didn't show a significant difference statistically (p=0.126) Conclusion : In diagnosis of thyroid tumor, SUV and radioactivity depending on $^{18}F$-FDG uptake showed high similarity with coefficient of determination (R2=0.939) and malignant evaluation results using dual time also showed similar aspect. Radioactivity for evaluation of malignant tumor didn't show better specificity or sensitivity than maxSUV.

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Effects of Hair Colors on the Image - Centered on Female Collegians in Their 20s -

  • Li, Eun-Ji;Shim, Boo-Ja
    • Journal of Fashion Business
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    • v.8 no.3
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    • pp.49-58
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    • 2004
  • In the modern society, already a popular and public part of fashion, hair coloring has the effect of optical illusion on image. This study therefor aims to reveal the effects of varied and fashionable hair coloring on the body images. This is a combination of an actual examination and an experimental study. In order to know the effects of hair colors on body image, 230 female collegians residing in Busan were given a questionnaire on the reality of hair dyeing. Based on the actual research, one subject was selected and stimuli were manufactured. The analysis and examination of the effects of hair dyeing have produced the following conclusions. (1) As a result of dispersion analysis about the image effect according to hair colors, a meaningful difference is recognized in the item and indicates that hair color variation influences the image effect. (2) As a result, extracting the factors that hair colors can influence the image, 3 factors were extracted. The first factor is an intellectual image, the second factor is an active image, and the third factor is a comfortable image. (3) Image effect in hair colors are as same next. Red and Orange color clearly indicate the image of 'charismatic', 'lively', 'positive', 'active', 'light' and 'gorgeous'. Blue and Green color indicates the image of 'unfriendly', 'hard', 'cold' and 'uneasy'. White color indicates the image of 'unfriendly', 'charismatic', 'gorgeous' and 'impure' then Black color has images of 'friendly', 'intellectual', 'indignified' and 'pure'. In other words, the result indicates rather a different tendency comparison with the general color image.

A Study on the Analysis Method of City Image : Focusing on the Image Comparison between Cities by MDS (도시 이미지 분석 기법에 관한 연구 : MDS(Multidimensional Scaling)에 의한 도시 간 이미지 비교)

  • 임승빈;최형석;변재상
    • Journal of the Korean Institute of Landscape Architecture
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    • v.32 no.1
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    • pp.47-56
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    • 2004
  • Rapid economic development in Korea caused functions of city functions such as concentration of population, deterioration of the quality of living environment and traffic congestion. Korean cities have lost their identity becausr they are merged functionally and physically with neighboring cities, forming one mesa-city. Unified shape and disorganized streets of cities often cause confusion among foreigners and visitors. It is very difficult for them to find their image in strange cities. It is, however, important to correctly analyze the image and meaning of cities for understanding its identity. The purpose of this study is to develop a method to analyze the city image by focusing on some of the main cities in Korea. For this purpose, the adjective questionnaire and multi-dimension scaling (MDS) are applied to the analysis of city image. Image analysis graph by MDS can visually present the general and integrate images. The results of this study are summarized as follows: The important factors for interpretation of city image are historical and industrial character. Seoul, Taegu and Pusan have industrial and complex city images. Kongju has historical city image, while Changwon has a modern image. Chuncheon belongs to a soft and small image. Each city has an alternative solution against a negative image, according to the image analysis graph.

Designation of a Road in Urban Area Using Rough Transform

  • Kim, Joon-Cheol;Park, Sung-Mo;Lee, Joon-whoan;Jeong, Soo
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.766-771
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    • 2002
  • Automatic change detection based on the vector-to-raster comparison is hard especially in high-resolution image. This paper proposes a method to designate roads in high-resolution image in sequential manner using the information from vector map in which Hough transform is used for reliability. By its linearity, the road of urban areas in a vector map can be easily parameterized. Following some pre-processing to remove undesirable objects, we obtain the edge map of raster image. Then the edge map is transformed to a parameter space to find the selected road from vector map. The comparison is done in the parameter space to find the best matching. The set of parameters of a road from vector map is treated as the constraints to do matching. After designating the road, we may overlay it on the raster image for precise monitoring. The results can be used for detection of changes in road object in a semi-automatic fashion.

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Accuracy Comparison of Direct Georeferencing and Indirect Georeferencing in the Mobile Mapping System

  • Bae Sang-Keun;Kim Byung-Guk;Sung Jung-Gon
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.656-660
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    • 2004
  • The Mobile Mapping System is an effective method to acquire the position and image data using vehicle equipped with the GPS (Global Positioning System), IMU (Inertial Measurement Unit), and CCD camera. It is used in various fields of road facility management, map update, and etc. In the general photogrammetry such as aerial photogrammetry, GCP (Ground Control Point)s are needed to compute the image exterior orientation elements (the position and attitude of camera). These points are measured by field survey at the time of data acquisition. But it costs much time and money. Moreover, it is not possible to make sufficient GCP as much as we want. However Mobile Mapping System is more efficient both in time and money because it can obtain the position and attitude of camera at the time of photographing. That is, Indirect Georeferencing must use GCP to compute the image exterior orientation elements, but on the other hand Direct Georeferencing can directly compute the image exterior orientation elements by GPS/INS. In this paper, we analyze about the positional accuracy comparison of ground point using the Direct Georeferencing and Indirect Georeferencing.

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Performance Comparison of Frequency-Based Watermarking Methods (주파수 기반 워터마킹 기법의 성능 비교)

  • Yim, Kyoung-Jin;Choi, Tae-Young
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.38 no.5
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    • pp.65-76
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    • 2001
  • In this paper, performance of frequency-based watermarking methods is compared, which are used to protect copyright of image data. For performance comparison of each transform method, a test image is transformed into frequency domain by a full- and block-discrete cosine transforms and wavelet transform, and after general image processing, robustness of each transform is evaluated with using the same watermark signals. Simulation results show that the watermarking method based on DCTs are more robust than WT. Especially, $8{\times}8$ BDCT is most robust for JPEG lossy compression and sharpening, while $8{\times}8$ FDCT is best. for smoothing and scaling. In addition, watermarking based on BDCT shows decreasing robustness for a larger block size, compared with general image processing.

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Comparison of Edge Localization Performance of Moment-Based Operators Using Target Image Data

  • Seo, Suyoung
    • Korean Journal of Remote Sensing
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    • v.32 no.1
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    • pp.13-24
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    • 2016
  • This paper presents a method to evaluate the performance of subpixel localization operators using target image data. Subpixel localization of edges is important to extract the precise shape of objects from images. In this study, each target image was designed to provide reference lines and edges to which the localization operators can be applied. We selected two types of moment-based operators: Gray-level Moment (GM) operator and Spatial Moment (SM) operator for comparison. The original edge localization operators with kernel size 5 are tested and their extended versions with kernel size 7 are also tested. Target images were collected with varying Camera-to-Object Distance (COD). From the target images, reference lines are estimated and edge profiles along the estimated reference lines are accumulated. Then, evaluation of the performance of edge localization operators was performed by comparing the locations calculated by each operator and by superimposing them on edge profiles. Also, enhancement of edge localization by increasing the kernel size was also quantified. The experimental result shows that the SM operator whose kernel size is 7 provides higher accuracy than other operators implemented in this study.