• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2022.06a
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• pp.146-149
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• 2022

기존 RDO(Rate Distortion Optimization) 기반 압축 방식은 압축 성능에 초점을 두기 때문에 영상 내 인지 특성이 무시될 수 있다. 따라서 RoI(Region of Interest)을 기반으로 압축률을 조절하는 연구가 고안[1, 2, 3, 4] 되었으며, HVS(Human Visual System) 관점에서 영상 내 중요한 부분에 대해 더 높은 품질로 영상을 압축하는 연구가 대부분이다. 최근 인공지능 기술이 발전함에 따라 지능형 영상 분석에 대한 수요가 증가하고 있으며, 이에 따라 머신 비전을 위한 영상 부호화 및 효율적인 전송에 대한 필요성이 대두되고 있다. 본 논문에서는 VVC(Versatile Video Coding)의 dQP(delta Quantization Parameter)를 활용하여 RoI(Region of Interest) 기반압축 방법을 제안하고, 두가지의 RoI 추출 방식을 소개한다. Detectron2 Faster R-CNN X101-FPN [5]의 첫번째 탐지기를 통해 후보 영역 기반 RoI 을 추출하고, 두번째 탐지기를 통해 객체 기반 RoI 을 추출하여, 영상 내 객체 부분과 비객체 부분으로 나누어 서로 다른 압축률로 압축을 수행하였으며, 이에 따른 성능을 비교하고자 한다.

• Journal of information and communication convergence engineering
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• v.22 no.1
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• pp.80-87
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• 2024

The Manchu language holds historical significance, but a complete dataset of Manchu script letters for training optical character recognition machine-learning models is currently unavailable. Therefore, this paper describes the process of creating a robust dataset of extracted Manchu script letters. Rather than performing automatic letter segmentation based on whitespace or the thickness of the central word stem, an image of the Manchu script was manually inspected, and one copy of the desired letter was selected as a region of interest. This selected region of interest was used as a template to match all other occurrences of the same letter within the Manchu script image. Although the dataset in this study contained only 4,000 images of five Manchu script letters, these letters were collected from twenty-eight writing styles. A full dataset of Manchu letters is expected to be obtained through this process. The collected dataset was normalized and trained using a simple convolutional neural network to verify its effectiveness.

• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.1
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• pp.43-47
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• 2013

Purpose: A duplicated ureter is congenital renal malformations with ureter in two. Patients with duplicated ureter are in force to $^{99m}Tc-DMSA$ scan at surgery before and after. In existing examination, at produce result after $^{99m}Tc-DMSA$ scan, didn't compare to upper pole and lower pole with malformed kidney and compared to only relative uptake ratio. Therefore, this study will examine about utility of set a partial region of interest and to functional recovery of renal cell through change of upper pole uptake ratio of malformed kidney by setting each partial region of interest in upper pole and lower pole of malformed kidney in $^{99m}Tc-DMSA$ examination in surgery before and after. Materials and Methods: Pediatric patients with malformed kidney of incomplete duplicated ureter, 15 patients were enrolled in this study. Scanning were scan 3 to 4 hours after injection of $^{99m}Tc-DMSA$ 1.5 ~ 1.9 MBq/kg. Region of interest were each set in normal kidney, upper pole and lower pole with malformed kidney. Region of interest were set with same condition and method to images of surgery before and after that radio technologist 1 person, resident of nuclear medicine 1 person and doctor of urology together. Therefore, this study were compared to uptake ratio (A: B: C) that normal kidney (A), lower pole of malformed kidney (B) and upper pole of malformed kidney (C) about uptake ratio changes of malformed kidney in follow-up examination of surgery before and after. Results: When compared to 15 patients, uptake ratios were increased 7 persons and decreased 8 persons. Among increased 7 persons, it were periods of follow-up examination that 2 persons were 14 months, 4 persons were 12 months and 1 person was 8 months after surgery. Among decreased 8 persons, it were periods of follow-up examination that 4 persons were 12 months 3 persons were 6 months and 1 persons were 4 months after surgery. Conclusion: Existing study could not see the exact uptake ratio changes of malformed kidney because using only the overall Left-Right kidney uptake ratios. But a setting partial region of interest was able to see exactly what changes in the uptake of each upper pole and lower pole of malformed kidney. Because recovery of renal parenchymal cells is difficult in an evaluation of short period of time, follow-up examination should be made in long period of time. How to set up partial region of interest be thought that it would be useful.

• Journal of Biomedical Engineering Research
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• v.26 no.5
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• pp.295-300
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• 2005

We introduce an x-ray micro tomography system capable of high resolution imaging of a local region inside a small animal. By combining two kinds of projection data, one from a full field-of-view (FOV) scan of the whole body and the other from a limited FOV scan of the region of interest, we have obtained zoomed-in images of the region of interest without any contrast a nomalies. We have integrated a micro tomography system using a micro-focus x-ray source, a $1248\times1248$ flat-panel x-ray detector, and a precision scan mechanism. Using the cross-sectional images taken with the zoom-in micro tomography system, we measured trabecular thicknesses of femur bones in postmortem rats. To compensate the limited spatial resolution in the zoom-in micro tomography images, we used the fuzzy distance transform for the calculation of the trabecular thickness. To validate the trabecular thickness measurement with the zoom-in micro tomography images, we compared the measurement results with the ones obtained from the conventional micro tomography images of the extracted bone samples.

• Journal of Biomedical Engineering Research
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• v.29 no.2
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• pp.107-113
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• 2008

We introduce a rotating-gantry-based x-ray micro-tomography system to be used for small animal imaging studies. It has the zoom-in imaging capability for high resolution imaging of a local region inside the animal subject without any contrast anomalies arising from truncation of the projection data. With the sliding mechanism mounted on the rotating gantry holding the x-ray source and the x-ray detector, we can control the magnification ratio of the x-ray projection data. By combining the projection data from the large field of view (FOV) scan of the whole animal subject and the projection data from the small FOV scan of the region of interest, we can obtain artifact-free zoomed-in images of the region of interest. For the acquisition of x-ray projection data, we use a $1248{\times}1248$ flat-panel x-ray detector with the pixel pitch of 100 mm. It has been experimentally found that the developed system has the spatial resolution of up to 121p/mm when the highest magnification ratio of 5:1 is applied to the zoom-in imaging. We present some in vivo rat femur images to demonstrate utility of the developed system for small animal imaging.

• Journal of KIISE:Computer Systems and Theory
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• v.37 no.5
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• pp.314-318
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• 2010

This paper proposes an image retrieval method based on the Multiple Region-of-Interest. In the proposed method, the image is segmented into blocks, among which the blocks overlapped with multiple ROIs are selected. The similarity of images is measured using the MPEG-7 dominant color descriptor(DCD) and considering the relative location of the overlapped blocks. The experimental results showed that the proposed method improves the retrieval performance than the previous methods using the global DCD or comparing the blocks at the same position. In addition, the method that considers the relative position of blocks overlapped with the multiple ROIs also showed a better performance than the existing methods.

• Journal of Korea Multimedia Society
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• v.21 no.8
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• pp.876-887
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• 2018

In this paper, we propose an robust CAMShift method to track stage objects with a camera. In order to solve the problem of tracking object misdetection in existing CAMShift technique, MBR region is detected to separate the background and the subject, and the subject size of the region of interest is calculated to solve the problem of erroneously detecting a large region having a similar color distribution ratio. Also, by applying the color corelogram and MB-LBP to the part that can not be solved by the color ratio and the size limitation, accurate texture tracking is enabled by reflecting the texture characteristics. Experimental results show that the proposed method has good tracking performance for objects that do not deviate from the size of the subject set in the area of interest and accurately extracts the texture characteristics of different subjects with similar color distribution ratios.

• The KIPS Transactions:PartB
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• v.13B no.3 s.106
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• pp.301-308
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• 2006

Currently, the preferred processing of a user-centered ROI(Region-of-Interest) or a specific region of image than the transmission and decompression of a full image is needed in different applications. This preferred processing has been actively studied about from the ROI coding methods in JPEG2000 standards to the new methods complementing them. But, there does not exist an ROI coding method suitable for all applications. Therefore, this study shows a criterion of selection according to the application requirements for applying an adequate ROI coding method in JPEG2000 applications, and shows the experimental results deciding efficient parameters in the selected methods.

• Journal of Information Technology and Architecture
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• v.10 no.1
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• pp.113-122
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• 2013

In this paper, we propose the method that automatically corrects the composition of a picture stylishly as well as reliably by cropping pictures based on the Rule of Thirds. The region of interest (ROI) is extracted from a picture by applying the Saliency Map and the Image Segmentation technology, the composition of the photo is amended based on this area to satisfy the Rule of Thirds. In addition, since the face region of the person is added to ROI by the Face Detection technique and the composition is amended by the various scenario according to ROI, the little more natural picture is acquired. The experimental result shows that the photo of the corrected composition was naturally amended compared with the original photo.

• Journal of the Korea Society of Computer and Information
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• v.21 no.11
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• pp.17-21
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• 2016

Heterogeneity assessment of tumor in oncology is important for diagnosis of cancer and therapy. The aim of this study was performed assess heterogeneity tumor region in PET image using texture analysis. For assessment of heterogeneity tumor in PET image, we inserted sphere phantom in torso phantom. Cu-64 labeled radioisotope was administrated by 156.84 MBq in torso phantom. PET/CT image was acquired by PET/CT scanner (Discovery 710, GE Healthcare, Milwaukee, WI). The texture analysis of PET images was calculated using occurrence probability of gray level co-occurrence matrix. Energy and entropy is one of results of texture analysis. We performed the texture analysis in tumor, liver, and background. Assessment textural features of region-of-interest (ROI) in torso phantom used in-house software. We calculated the textural features of torso phantom in PET image using texture analysis. Calculated entropy in tumor, liver, and background were 5.322, 7.639, and 7.818. The further study will perform assessment of heterogeneity using clinical tumor PET image.