• Title/Summary/Keyword: False Region

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SIFT-based Stereo Matching to Compensate Occluded Regions and Remove False Matching for 3D Reconstruction

  • Shin, Do-Kyung;Lee, Jeong-Ho;Moon, Young-Shik
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.01a
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    • pp.418-422
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    • 2009
  • Generally, algorithms for generating disparity maps can be clssified into two categories: region-based method and feature-based method. The main focus of this research is to generate a disparity map with an accuracy depth information for 3-dimensional reconstructing. Basically, the region-based method and the feature-based method are simultaneously included in the proposed algorithm, so that the existing problems including false matching and occlusion can be effectively solved. As a region-based method, regions of false matching are extracted by the proposed MMAD(Modified Mean of Absolute Differences) algorithm which is a modification of the existing MAD(Mean of Absolute Differences) algorithm. As a feature-based method, the proposed method eliminates false matching errors by calculating the vector with SIFT and compensates the occluded regions by using a pair of adjacent SIFT matching points, so that the errors are reduced and the disparity map becomes more accurate.

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TRAUMATIC FALSE ANEURYSM OF THE LINGUAL ARTERY - A CASE REPORT- (설동맥에 발생한 외상성 위동맥류)

  • Min, Gyung-In;Lee, Ju-Hyun;Seo, Kyung-Suk;Kim, Chul-Hwan
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.27 no.6
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    • pp.551-555
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    • 2001
  • False aneurysms(Pseudoaneurysms) and arteriovenous fistulas have only rarely been reported in the facial region. In this region the false aneurysm arises most frequently in the superficial temporal and facial artery, but other branches of the external carotid are sometimes involved, including the maxillary and lingual artery. False aneurysms can be occurred by blunt trauma that either laceration or rupture the full thickness of the arterial wall. The diagnosis of a false arterial aneurysm can be often made solely on the basis of physical examination. Angiography is helpful for conformation, for delineating the lesion and its vascular supply, and for ruling out the presence of associated vascular lesions such as arteriovenous fistulas. Ultrasonography may also be useful in delineating lesions that are not easily accessible for physical examination. Treatment of false aneurysms is excision, ligation, and arterial embolization. This is a case of false aneurysm of the lingual artery after facial trauma caused by traffic accident. The lesion was successfully treated by embolization and ligation of the lingual and facial branches of the external carotid artery.

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AUTOMATIC MOTION DETECTION USING FALSE BACKGROUND ELIMINATION

  • Seo, Jin Keun;Lee, Sukho
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.17 no.1
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    • pp.47-54
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    • 2013
  • This work deals with automatic motion detection for with surveillance tracking that aims to provide high-lighting movable objects which is discriminated from moving backgrounds such as moving trees, etc. For this aim, we perform a false background region detection together with an initial foreground detection. The false background detection detects the moving backgrounds, which become eliminated from the initial foreground detection. This false background detection is done by performing the bimodal segmentation on a deformed image, which is constructed using the information of the dominant colors in the background.

Dyeing Properties of Nylon Textured Yarn according to False Twist Texturing Parameters(I) - Effect of Draw Ratio - (가연조건에 따른 나일론 섬유의 염색특성 (I) - 연신비의 영향 -)

  • Hu, Jong-Tea
    • Textile Coloration and Finishing
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    • v.20 no.2
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    • pp.47-52
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    • 2008
  • Nylon textured yarn is usually manufactured by disk type false twist texturing. Dyeing properties of nylon textured yam have not been studied yet. In this study, dyeing properties of nylon textured yam according to draw ratio out of process parameters were investigated. The fact that microstructure of nylon textured yarn in amorphous region particularly is transformed by draw ratio was confirmed indirectly by measurement of dyeing rate because dyeing rate was affected by the structure of amorphous region. Dyeing rate at draw ratio 1.29 was the lowest because the higher draw ratio increase amorphous orientation and disturb dye diffusion into amorphous region. The microstructure according draw ratio was indirectly confirmed by 5% strength, tenacity, elongation. But difference in K/S value and fastness was insignificant.

Detection Copy-Move Forgery in Image Via Quaternion Polar Harmonic Transforms

  • Thajeel, Salam A.;Mahmood, Ali Shakir;Humood, Waleed Rasheed;Sulong, Ghazali
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.8
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    • pp.4005-4025
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    • 2019
  • Copy-move forgery (CMF) in digital images is a detrimental tampering of artefacts that requires precise detection and analysis. CMF is performed by copying and pasting a part of an image into other portions of it. Despite several efforts to detect CMF, accurate identification of noise, blur and rotated region-mediated forged image areas is still difficult. A novel algorithm is developed on the basis of quaternion polar complex exponential transform (QPCET) to detect CMF and is conducted involving a few steps. Firstly, the suspicious image is divided into overlapping blocks. Secondly, invariant features for each block are extracted using QPCET. Thirdly, the duplicated image blocks are determined using k-dimensional tree (kd-tree) block matching. Lastly, a new technique is introduced to reduce the flat region-mediated false matches. Experiments are performed on numerous images selected from the CoMoFoD database. MATLAB 2017b is used to employ the proposed method. Metrics such as correct and false detection ratios are utilised to evaluate the performance of the proposed CMF detection method. Experimental results demonstrate the precise and efficient CMF detection capacity of the proposed approach even under image distortion including rotation, scaling, additive noise, blurring, brightness, colour reduction and JPEG compression. Furthermore, our method can solve the false match problem and outperform existing ones in terms of precision and false positive rate. The proposed approach may serve as a basis for accurate digital image forensic investigations.

A Shadow Region Suppression Method using Intensity Projection and Converting Energy to Improve the Performance of Probabilistic Background Subtraction (확률기반 배경제거 기법의 향상을 위한 밝기 사영 및 변환에너지 기반 그림자 영역 제거 방법)

  • Hwang, Soon-Min;Kang, Dong-Joong
    • Journal of Institute of Control, Robotics and Systems
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    • v.16 no.1
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    • pp.69-76
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    • 2010
  • The segmentation of moving object in video sequence is a core technique of intelligent image processing system such as video surveillance, traffic monitoring and human tracking. A typical method to segment a moving region from the background is the background subtraction. The steps of background subtraction involve calculating a reference image, subtracting new frame from reference image and then thresholding the subtracted result. One of famous background modeling is Gaussian mixture model (GMM). Even though the method is known efficient and exact, GMM suffers from a problem that includes false pixels in ROI (region of interest), specifically shadow pixels. These false pixels cause fail of the post-processing tasks such as tracking and object recognition. This paper presents a method for removing false pixels included in ROT. First, we subdivide a ROI by using shape characteristics of detected objects. Then, a method is proposed to classify pixels from using histogram characteristic and comparing difference of energy that converts the color value of pixel into grayscale value, in order to estimate whether the pixels belong to moving object area or shadow area. The method is applied to real video sequence and the performance is verified.

Removing False Contour Artifact for Bit-depth Expansion

  • Kim, Seyun;Choo, Sungkwon;Cho, Nam Ik
    • IEIE Transactions on Smart Processing and Computing
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    • v.2 no.2
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    • pp.97-101
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    • 2013
  • Bit-depth expansion is a process of enhancing the image quality by increasing the number of intensity levels. To solve this problem, a hybrid method is proposed, where the pixels are categorized into smooth and complex regions, and are processed using different methods. The pixels in the smooth region are reconstructed with a smooth prior, and a Bayesian estimator is used for the pixels in the complex region. The proposed method effectively removes the false contour artifacts while requiring less computation than conventional methods. In addition, the method shows good quantitative performance, and the PSNR gains over the best existing method are 1.45 dB and 0.26 dB for 4 bits and 3 bits expansion cases, respectively.

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Method of Human Detection using Edge Symmetry and Feature Vector (에지 대칭과 특징 벡터를 이용한 사람 검출 방법)

  • Byun, Oh-Sung
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.8
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    • pp.57-66
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    • 2011
  • In this paper, it is proposed for algorithm to detect human efficiently using a edge symmetry and gradient directional characteristics in realtime by the feature extraction in a single input image. Proposed algorithm is composed of three stages, preprocessing, region partition of human candidates, verification of candidate regions. Here, preprocessing stage is strong the image regardless of the intensity and brightness of surrounding environment, also detects a contour with characteristics of human as considering the shape features size and the condition of human for characteristic of human. And stage for region partition of human candidates has separated the region with edge symmetry for human and size in the detected contour, also divided 1st candidates region with applying the adaboost algorithm. Finally, the candidate region verification stage makes excellent the performance for the false detection by verifying the candidate region using feature vector of a gradient for divided local area and classifier. The results of the simulations, which is applying the proposed algorithm, the processing speed of the proposed algorithms is improved approximately 1.7 times, also, the FNR(False Negative Rate) is confirmed to be better 3% than the conventional algorithm which is a single structure algorithm.

Microcalcification Extraction by Using Automatic Thredholding Based on Region Growing (영역 성장법을 기반으로 자동적인 임계치 설정을 이용한 미세 석회화 추출)

  • 원철호;권용준;이정현;박희준;임성운;김명남;조진호
    • Journal of Biomedical Engineering Research
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    • v.25 no.4
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    • pp.235-242
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    • 2004
  • In this paper, we proposed the algorithm for detection of microtalcification by automatic threshold decision based on region growing method. The region for optimal threshold is grown from local maximum pixel by increasing repeatedly threshold in microralcification candidate region. Then, the optimal threshold is automatically decided at the maximum value of the contrast and edge sharpness in this region. Microcalcifications could be efficiently detected as satisfied result that true positive ratio is 81.5% and average false positive numbers are 1.1 about total 299 microcalcifirations in real image. In a result, we showed that this algorithm can be used to aid diagnostic-radiologist for the diagnosis of the early phase of breast cancer.

The Analysis of Types and Historical Review of False Sleeves (False Sleeves의 유형분석과 복식사적 고잘)

  • Kwon, Soo-Hyun;Kang, Soon-Che
    • Journal of the Korean Society of Costume
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    • v.60 no.10
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    • pp.163-179
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    • 2010
  • False sleeves are 'the sleeves that are attached to clothes but exist just as a part without any function to put arms in them.' They are different from sleeves to put arms in them and are to follow the trend or a way of wearing clothes. They are mostly found in medieval Europe's decorative sleeves named 'Hanging sleeves', but they are also found in Eastern region, too. They are found in sleeves that attached women's headgear in East and Middle Asia, and also in high-class male caftan in Ottoman Turk in the 16th and 17th century. False sleeves can be divided into two kinds by shapes. The first ones are the decorative sleeves of which trunk-shaped sleeves hang around the whole or part of the arm hole but have no function to put arms in them; this is called as 'sleeve-shaped False sleeves'. These sleeves are found in women's headgear in medieval Europe, Ottoman Turk, and East and Middle Asia. False sleeves in Europe and Ottoman Turk played a role in showing wealth and power while those in East and Middle Asia had a great role in highlighting the costume's decorative effect. The second ones are the sleeves hanging down from the arms by attaching long cloth to the arm hole, in design; these are named as 'cape-shaped False sleeves.' This style is found only in medieval Europe, and presumably, these cape-shaped false sleeves may have played a role in boasting of one's wealth and power.