• Title/Summary/Keyword: Region of interest (ROI)

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De-interlacing Algorithm Using Integral Projection-based Motion Estimation Considering Region Of Interest (관심영역 단위의 적분 프로젝션기반 움직임 추정을 사용한 순차주사화 알고리즘)

  • Kim, Young-Duk;Chang, Joon-Young;Kang, Moon-Gi
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.45 no.3
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    • pp.20-29
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    • 2008
  • In this paper, we propose a do-interlacing algorithm using integral projection-based motion estimation considering Region Of Interest(ROI). The proposed motion estimation method finds the motion of the given ROI accurately with low computational cost. In order to incorporate the motion estimation in do-interlacing, an entire image is first segmented into multiple ROIs according to the temporally predicted block-wise motion types and spatial positions. Then, motion vectors of respective ROIs are obtained by the integral projection method. In this paper, totally five ROIs, one for the global motion and four for the local motions, are made, and therefore, five motion vectors are produced for each field. By using the estimated motion vectors, motion compensation is performed for increasing the vortical resolution of the converted frames. Finally, do-interlaced frames are obtained by effectively combining the results of motion compensation and stable intra-field do-interlacing according to the reliability of motion compensation. Experimental results show that the proposed algorithm provides better image quality than existing algorithms in both subjective and objective measures.

Selective Encryption Scheme Based on Region of Interest for Medical Images (의료 영상을 위한 관심영역 기반 선택적 암호 기법)

  • Lee, Won-Young;Ou, Yang;Rhee, Kyung-Hyune
    • Journal of Korea Multimedia Society
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    • v.11 no.5
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    • pp.588-596
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    • 2008
  • For the patients' privacy, secure access control of medical images is essentially necessary. In this paper, two types of Region of Interest (ROI)-based selective encryption schemes are proposed, which concentrate on the security of crucial parts in medical images. The first scheme randomly inverts the most significant bits of ROI coefficients in several high frequency subbands in the transform domain, which only incurs little loss on compression efficiency. The second scheme employs a symmetric key encryption to encrypt selectively the ROI data in the final code-stream, which provides sufficient confidentiality. Both of two schemes are backward compatible so as to ensure a standard bitstream compliant decoder so the encrypted images can be reconstructed without any crash.

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Comparison of Hounsfield Units by Changing in Size of Physical Area and Setting Size o f Region o f Interest b y Using the CT Phantom Made with a 3D Printer (3D 프린터로 제작된 CT 팬톰을 이용한 물리적 관심영역과 설정 관심영역의 크기에 따른 하운스필드의 비교)

  • Seoung, Youl-Hun
    • Journal of radiological science and technology
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    • v.38 no.4
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    • pp.421-427
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    • 2015
  • In this study, we have observed the change of the Hounsfield (HU) in the alteration of by changing in size of physical area and setting size of region of interest (ROI) at focus on kVp and mAs. Four-channel multi-detector computed tomography was used to get transverse axial scanning images and HU. Three dimensional printer which is type of fused deposition modeling (FDM) was used to produce the Phantom. The structure of the phantom was designed to be a type of cylinder that contains 33 mm, 24 mm, 19 mm, 16 mm, 9 mm size of circle holes that are symmetrically located. It was charged with mixing iodine contrast agent and distilled water in the holes. The images were gained with changing by 90 kVp, 120 kVp, 140 kVp and 50 mAs, 100 mAs, 150 mAs, respectively. The 'image J' was used to get the HU measurement of gained images of ROI. As a result, it was confirmed that kVp affects to HU more than mAs. And it is suggested that the smaller size of physical area, the more decreasing HU even in material of a uniform density and the smaller setting size of ROI, the more increasing HU. Therefore, it is reason that to set maximum ROI within 5 HU is the best way to minimize in the alteration of by changing in size of physical area and setting size of region of interest.

The High-Speed Extraction of Interest Region in the Parcel Image of Large Size (대용량 소포영상에서 관심영역 고속추출 방법에 관한 연구)

  • Park, Moon-Sung;Bak, Sang-Eun;Kim, In-Soo;Kim, Hye-Kyu;Jung, Hoe-Kyung
    • The KIPS Transactions:PartD
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    • v.11D no.3
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    • pp.691-702
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    • 2004
  • In this paper, we propose a sequence of method which extrats ROIs(Region of Interests) rapidly from the parcel image of large size. In the proposed method, original image is spilt into the small masks, and the meaningful masks, the ROIs, are extracted by two criterions sequentially The first criterion is difference of pixel value between Inner points, and the second is deviation of it. After processing, some informational ROIs-the areas of bar code, characters, label and the outline of object-are acquired. Using diagonal axis of each ROI and the feature of various 2D bar code, the area of 2D bar code can be extracted from the ROIs. From an experiment using above methods, various ROIs are extracted less than 200msec from large-size parcel image, and 2D bar code region is selected by the accuracy of 100%.

The Study about the Differential compression based on the ROI(Region Of Interest) (ROI(Region Of Interest)기반의 차등적 이미지 압축에 관한 연구)

  • Yun, Chi-Hwan;Ko, Sun-Woo;Lee, Geun-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.3
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    • pp.679-686
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    • 2014
  • Recently, users can get countless images and videos by network. So, the compression technology of image and video is researched more and more. However, the situation which is the interested range of the image is occurred. For instance, since the region of face is more important than background, the image compression technology bases on the region of interest (ROI) is necessary, in the ATM environment. In this research, given the human visual system, which are not sensitive to illumination variations at very dark and light regions of image, we calculate the standard deviation of block and use this value to define the ROI. In encoding process, the relatively high quality can be obtained at the ROI and the relatively low quality can be obtained at the non ROI. In proposed scheme, the feature which is the encoding process according to subjectively image quality can be demonstrated. Finally, this proposed scheme is applied to JPEG standard. The experimental results demonstrate that proposed scheme can achieve better image quality at the high compression ratio.

Optimal ROI Determination for Obtaining PPG Signals from a Camera on a Smartphone

  • Lee, Keonsoo;Nam, Yunyoung
    • Journal of Electrical Engineering and Technology
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    • v.13 no.3
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    • pp.1371-1376
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    • 2018
  • Photoplethysmography (PPG) is a convenient method for monitoring a heart rhythm. In addition to specialized devices, smartphones can be used to obtain PPG signals. However, as smartphones are not intended for this purpose, optimization is required to efficiently obtain PPG signals. Determining the optimal region of interest (ROI) is one such optimization method. There are two significant advantages in employing an optimized ROI. One is that the computing load is decreased by reducing the image size used to extract the PPG signal. The other is that stronger and more reliable PPG signals are obtained by removing noisy regions. In this paper, we propose an optimal ROI determination method by recursively splitting regions to locate the region that produces the strongest PPG signal.

Real-time face tracking for high-resolution intelligent surveillance system (고해상도 지능형 감시시스템을 위한 실시간 얼굴영역 추적)

  • 권오현;김상진;김영욱;백준기
    • Proceedings of the IEEK Conference
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    • 2003.11a
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    • pp.317-320
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    • 2003
  • In this paper, we present real-time, accurate face region detection and tracking technique for an intelligent surveillance system. It is very important to obtain the high-resolution images, which enables accurate identification of an object-of-interest. Conventional surveillance or security systems, however, usually provide poor image quality because they use one or more fixed cameras and keep recording scenes without any clue. We implemented a real-time surveillance system that tracks a moving person using pan-tilt-zoom (PTZ) cameras. While tracking, the region-of-interest (ROI) can be obtained by using a low-pass filter and background subtraction. Color information in the ROI is updated to extract features for optimal tracking and zooming. The experiment with real human faces showed highly acceptable results in the sense of both accuracy and computational efficiency.

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An Efficient Partial Matching System and Region-based Representation for 2D Images (2D 영상의 효과적인 부분 정합 시스템과 영역기반 영상 표현)

  • Kim, Seon-Jong
    • Journal of Institute of Control, Robotics and Systems
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    • v.13 no.9
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    • pp.868-874
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    • 2007
  • This paper proposes an efficient partial matching system and representation by using a region-based method for 2D image, and we applied to an extraction of the ROI(Region of Interest) according to its matching score. The matching templates consist of the global pattern and the local one. The global pattern can make it by using region-based relation between center region and its rest regions in an object. And, the local pattern can be obtained appling to the same method as global, except relation between objects. As the templates can be normalized, we use this templates for extraction of ROI with invariant to size and position. And, our system operates only one try to match, due to normalizing of region size. To use our system for searching and examining if it's the ROI by evaluating the matching function, at first, we are searching to find candidate regions with the global template. Then, we try to find the ROI among the candidates, and it works this time by using the local template. We experimented to the binary and the color image respectively, they showed that the proposed system can be used efficiently for representing of the template and the useful applications, such as partially retrievals of 2D image.

A Study on High-Speed Extraction of Bar Code Region for Parcel Automatic Identification (소포 자동식별을 위한 바코드 관심영역 고속 추출에 관한 연구)

  • Park, Moon-Sung;Kim, Jin-Suk;Kim, Hye-Kyu;Jung, Hoe-Kyung
    • The KIPS Transactions:PartD
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    • v.9D no.5
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    • pp.915-924
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    • 2002
  • Conventional Systems for parcel sorting consist of two sequences as loading the parcel into conveyor belt system and post-code input. Using bar code information, the parcels to be recorded and managed are recognized. This paper describes a 32 $\times$ 32 sized mini-block inspection to extract bar code Region of Interest (ROI) from the line Charged Coupled Device (CCD) camera capturing image of moving parcel at 2m/sec speed. Firstly, the Min-Max distribution of the mini-block has been applied to discard the background of parcel and region of conveying belts from the image. Secondly, the diagonal inspection has been used for the extraction of letters and bar code region. Five horizontal line scanning detects the number of edges and sizes and ROI has been acquired from the detection. The wrong detected area has been deleted by the comparison of group size from labeling processes. To correct excluded bar code region in mini-block processes and for analysis of bar code information, the extracted ROI 8 boundary points and decline distribution have been used with central axis line adjustment. The ROI extraction and central axis creation have become enable within 60~80msec, and the accuracy has been accomplished over 99.44 percentage.

Generation of ROI Enhanced High-resolution Depth Maps in Hybrid Camera System (복합형 카메라 시스템에서 관심영역이 향상된 고해상도 깊이맵 생성 방법)

  • Kim, Sung-Yeol;Ho, Yo-Sung
    • Journal of Broadcast Engineering
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    • v.13 no.5
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    • pp.596-601
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    • 2008
  • In this paper, we propose a new scheme to generate region-of-interest (ROI) enhanced depth maps in the hybrid camera system, which is composed of a low-resolution depth camera and a high-resolution stereoscopic camera. The proposed method creates an ROI depth map for the left image by carrying out a three-dimensional (3-D) warping operation onto the depth information obtained from the depth camera. Then, we generate a background depth map for the left image by applying a stereo matching algorithm onto the left and right images captured by the stereoscopic camera. Finally, we merge the ROI map with the background one to create the final depth map. The proposed method provides higher quality depth information on ROI than the previous methods.