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Desenvolvimento de um sistema de classificação de cores em tempo real para aplicações robóticas; Development of areal time color classifier to robotics applications

Penharbel, Éder Augusto
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 10/03/2008 PT
Relevância na Pesquisa
26.07%
Na visão computacional, a detecção de objetos é uma tarefa que tem signifgificativa importância. Podemos verificar isto através da existência de inúmeros métodos propostos na literatura. Cada um destes métodos se apóia em algumas características presentes na imagem para alcançar um desempenho eficiente. Considerando ambientes que utilizam cores para determinação de objetos presentes em uma imagem, é possível utilizá-las como características que permitam detectar os objetos. Neste trabalho, são investigados dois classificadores de cores. O primeiro é baseado em limiarização no espaço HSV e o segundo é constituído de um mapa auto-organizável para classificação dos pixels no espaço RGB. Objetivando a construção de um sistema classificador de cores eficiiente, capaz de processar vídeo em tempo real, é proposta uma técnica que se baseia no conceito de quantização. Outro aspecto investigado foi a detecção de movimento para evitar o processamento de pontos indesejados. O desempenho do sistema de classificação de cores é avaliado em um ambiente de futebol de robôs da categoria Mirosot, que é um ambiente dinâmico e que exige que todo o processamento da imagem seja rápido de modo a detectar corretamente todos objetos presentes em cada quadro. Os resultados mostram que o classificador de cores é capaz de detectar todos objetos no ambiente de futebol de robôs...

Mistura de cores: uma nova abordagem para processamento de cores e sua aplicação na segmentação de imagens; Colors mixture: a new approach for color processing and its application in image segmentation

Severino Junior, Osvaldo
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 28/05/2009 PT
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26.18%
Inspirado nas técnicas utilizadas por pintores que sobrepõem camadas de tintas de diversos matizes na geração de uma tela artística e também observando-se a distribuição da quantidade dos cones na retina do olho humano na interpretação destas cores, este trabalho propõe uma técnica de processamento de imagens baseada na mistura de cores. Trata-se de um método de quantização de cores estático que expressa a proporção das cores preto, azul, verde, ciano, vermelho, magenta, amarelo e branco obtida pela representação binária da cor que compõe os pixels de uma imagem RGB com 8 bits por canal. O histograma da mistura é denominado de misturograma e gera planos que interceptam o espaço RGB, definindo o espaço de cor HSM (Hue, Saturation and Mixture). A posição destes planos dentro do cubo RGB é modelada por meio da distribuição dos cones sensíveis aos comprimentos de onda curta (Short), média (Middle) e longa (Long) consideradas para a retina humana. Para demonstrar a aplicabilidade do espaço de cor HSM, é proposta, neste trabalho, a segmentação dos pixels de uma imagem digital em pele humana ou não pele com o uso dessa nova abordagem. Para análise de desempenho da mistura de cores foi implementado um método tradicional no espaço de cor RGB e também usando uma distribuição Gaussiana nos espaços de cores HSV e HSM. Os resultados obtidos demonstram o potencial da técnica que emprega a mistura de cores para a segmentação de imagens digitais coloridas. Verificou-se também que...

JSEG-based image segmentation in computer vision for agricultural mobile robot navigation

Lulio, Luciano C.; Tronco, Mario L.; Porto, Arthur J. V.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 240-245
ENG
Relevância na Pesquisa
46.07%
This project aims to apply image processing techniques in computer vision featuring an omnidirectional vision system to agricultural mobile robots (AMR) used for trajectory navigation problems, as well as localization matters. To carry through this task, computational methods based on the JSEG algorithm were used to provide the classification and the characterization of such problems, together with Artificial Neural Networks (ANN) for pattern recognition. Therefore, it was possible to run simulations and carry out analyses of the performance of JSEG image segmentation technique through Matlab/Octave platforms, along with the application of customized Back-propagation algorithm and statistical methods in a Simulink environment. Having the aforementioned procedures been done, it was practicable to classify and also characterize the HSV space color segments, not to mention allow the recognition of patterns in which reasonably accurate results were obtained.

ANN statistical image recognition method for computer vision in agricultural mobile robot navigation

Lulio, Luciano C.; Tronco, Mario L.; Porto, Arthur J. V.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 1771-1776
ENG
Relevância na Pesquisa
46.07%
The main application area in this project, is to deploy image processing and segmentation techniques in computer vision through an omnidirectional vision system to agricultural mobile robots (AMR) used for trajectory navigation problems, as well as localization matters. Thereby, computational methods based on the JSEG algorithm were used to provide the classification and the characterization of such problems, together with Artificial Neural Networks (ANN) for image recognition. Hence, it was possible to run simulations and carry out analyses of the performance of JSEG image segmentation technique through Matlab/Octave computational platforms, along with the application of customized Back-propagation Multilayer Perceptron (MLP) algorithm and statistical methods as structured heuristics methods in a Simulink environment. Having the aforementioned procedures been done, it was practicable to classify and also characterize the HSV space color segments, not to mention allow the recognition of segmented images in which reasonably accurate results were obtained. © 2010 IEEE.

Pattern recognition structured heuristics methods for image processing in mobile robot navigation

Lulio, Luciano C.; Tronco, Mario L.; Porto, Arthur J. V.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 4970-4975
ENG
Relevância na Pesquisa
46.07%
In this project, the main focus is to apply image processing techniques in computer vision through an omnidirectional vision system to agricultural mobile robots (AMR) used for trajectory navigation problems, as well as localization matters. To carry through this task, computational methods based on the JSEG algorithm were used to provide the classification and the characterization of such problems, together with Artificial Neural Networks (ANN) for pattern recognition. Therefore, it was possible to run simulations and carry out analyses of the performance of JSEG image segmentation technique through Matlab/Octave platforms, along with the application of customized Back-propagation algorithm and statistical methods as structured heuristics methods in a Simulink environment. Having the aforementioned procedures been done, it was practicable to classify and also characterize the HSV space color segments, not to mention allow the recognition of patterns in which reasonably accurate results were obtained. ©2010 IEEE.

The Herpes Simplex Virus Type 1 UL17 Gene Encodes Virion Tegument Proteins That Are Required for Cleavage and Packaging of Viral DNA

Salmon, Brandy; Cunningham, Charles; Davison, Andrew J.; Harris, Wendy J.; Baines, Joel D.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /05/1998 EN
Relevância na Pesquisa
16.3%
Previous studies have suggested that the UL17 gene of herpes simplex virus type 1 (HSV-1) is essential for virus replication. In this study, viral mutants incorporating either a lacZ expression cassette in place of 1,490 bp of the 2,109-bp UL17 open reading frame [HSV-1(ΔUL17)] or a DNA oligomer containing an in-frame stop codon inserted 778 bp from the 5′ end of the UL17 open reading frame [HSV-1(UL17-stop)] were plaque purified on engineered cell lines containing the UL17 gene. A virus derived from HSV-1(UL17-stop) but containing a restored UL17 gene was also constructed and was designated HSV-1(UL17-restored). The latter virus formed plaques and cleaved genomic viral DNA in a manner indistinguishable from wild-type virus. Neither HSV-1(ΔUL17) nor HSV-1(UL17-stop) formed plaques or produced infectious progeny when propagated on noncomplementing Vero cells. Furthermore, genomic end-specific restriction fragments were not detected in DNA purified from noncomplementing cells infected with HSV-1(ΔUL17) or HSV-1(UL17-stop), whereas end-specific fragments were readily detected when the viruses were propagated on complementing cells. Electron micrographs of thin sections of cells infected with HSV-1(ΔUL17) or HSV-1(UL17-stop) illustrated that empty capsids accumulated in the nuclei of Vero cells...

Herpes simplex virus type 1 glycoprotein K is not essential for infectious virus production in actively replicating cells but is required for efficient envelopment and translocation of infectious virions from the cytoplasm to the extracellular space.

Jayachandra, S; Baghian, A; Kousoulas, K G
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1997 EN
Relevância na Pesquisa
25.98%
We characterized the glycoprotein K (gK)-null herpes simplex virus type 1 [HSV-1] (KOS) delta gK and compared it to the gK-null virus HSV-1 F-gKbeta (L. Hutchinson et al., J. Virol. 69:5401-5413, 1995). delta gK and F-gKbeta mutant viruses produced small plaques on Vero cell monolayers at 48 h postinfection. F-gKbeta caused extensive fusion of 143TK cells that was sensitive to melittin, a specific inhibitor of gK-induced cell fusion, while delta gK virus did not fuse 143TK cells. A recombinant plasmid containing the truncated gK gene specified by F-gKbeta failed to rescue the ICP27-null virus KOS (d27-1), while a plasmid with the delta gK deletion rescued the d27-1 virus efficiently. delta gK virus yield was approximately 100,000-fold lower in stationary cells than in actively replicating Vero cells. The plaquing efficiencies of delta gK and F-gKbeta virus stocks on VK302 cells were similar, while the plaquing efficiency of F-gKbeta virus stocks on Vero cells was reduced nearly 10,000-fold in comparison to that of delta gK virus. Mutant delta gK and F-gKbeta infectious virions accumulated within Vero and HEp-2 cells but failed to translocate to extracellular spaces. delta gK capsids accumulated in the nuclei of Vero but not HEp-2 cells. Enveloped delta gK virions were visualized in the cytoplasms of both Vero and HEp-2 cells...

Herpesvirus gB-Induced Fusion between the Virion Envelope and Outer Nuclear Membrane during Virus Egress Is Regulated by the Viral US3 Kinase▿

Wisner, Todd W.; Wright, Catherine C.; Kato, Akihisa; Kawaguchi, Yasushi; Mou, Fan; Baines, Joel D.; Roller, Richard J.; Johnson, David C.
Fonte: American Society for Microbiology (ASM) Publicador: American Society for Microbiology (ASM)
Tipo: Artigo de Revista Científica
EN
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16.34%
Herpesvirus capsids collect along the inner surface of the nuclear envelope and bud into the perinuclear space. Enveloped virions then fuse with the outer nuclear membrane (NM). We previously showed that herpes simplex virus (HSV) glycoproteins gB and gH act in a redundant fashion to promote fusion between the virion envelope and the outer NM. HSV mutants lacking both gB and gH accumulate enveloped virions in herniations, vesicles that bulge into the nucleoplasm. Earlier studies had shown that HSV mutants lacking the viral serine/threonine kinase US3 also accumulate herniations. Here, we demonstrate that HSV gB is phosphorylated in a US3-dependent manner in HSV-infected cells, especially in a crude nuclear fraction. Moreover, US3 directly phosphorylated the gB cytoplasmic (CT) domain in in vitro assays. Deletion of gB in the context of a US3-null virus did not add substantially to defects in nuclear egress. The majority of the US3-dependent phosphorylation of gB involved the CT domain and amino acid T887, a residue present in a motif similar to that recognized by US3 in other proteins. HSV recombinants lacking gH and expressing either gB substitution mutation T887A or a gB truncated at residue 886 displayed substantial defects in nuclear egress. We concluded that phosphorylation of the gB CT domain is important for gB-mediated fusion with the outer NM. This suggested a model in which the US3 kinase is incorporated into the tegument layer (between the capsid and envelope) in HSV virions present in the perinuclear space. By this packaging...

Isolation and Preliminary Characterization of Herpes Simplex Virus 1 Primary Enveloped Virions from the Perinuclear Space▿

Padula, Maryn E.; Sydnor, Mariam L.; Wilson, Duncan W.
Fonte: American Society for Microbiology (ASM) Publicador: American Society for Microbiology (ASM)
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
26.08%
Herpes simplex virus 1 (HSV-1) nucleocapsids exit the nucleus by budding into the inner nuclear membrane, where they exist briefly as primary enveloped virions. These virus particles subsequently fuse their envelopes with the outer nuclear membrane, permitting nucleocapsids to then enter the cytoplasm and complete assembly. We have developed a method to isolate primary enveloped virions from HSV-1-infected cells and subjected the primary enveloped virion preparation to MALDI-MS/MS (matrix-assisted laser desorption ionization-tandem mass spectrometry) analyses. We identified most capsid proteins, a tegument protein (VP22), a glycoprotein (gD), and a cellular protein (annexin A2) in the primary enveloped virion preparation. We determined that annexin A2 does not play an essential role in infection under our experimental conditions. Elucidating the structure and biochemical properties of this unique virus assembly intermediate will provide new insights into HSV-1 biology.

Fusion between Perinuclear Virions and the Outer Nuclear Membrane Requires the Fusogenic Activity of Herpes Simplex Virus gB▿

Wright, Catherine C.; Wisner, Todd W.; Hannah, Brian P.; Eisenberg, Roselyn J.; Cohen, Gary H.; Johnson, David C.
Fonte: American Society for Microbiology (ASM) Publicador: American Society for Microbiology (ASM)
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
16.39%
Herpesviruses cross nuclear membranes (NMs) in two steps, as follows: (i) capsids assemble and bud through the inner NM into the perinuclear space, producing enveloped virus particles, and (ii) the envelopes of these virus particles fuse with the outer NM. Two herpes simplex virus (HSV) glycoproteins, gB and gH (the latter, likely complexed as a heterodimer with gL), are necessary for the second step of this process. Mutants lacking both gB and gH accumulate in the perinuclear space or in herniations (membrane vesicles derived from the inner NM). Both gB and gH/gL are also known to act directly in fusing the virion envelope with host cell membranes during HSV entry into cells, i.e., both glycoproteins appear to function directly in different aspects of the membrane fusion process. We hypothesized that HSV gB and gH/gL also act directly in the membrane fusion that occurs during virus egress from the nucleus. Previous studies of the role of gB and gH/gL in nuclear egress involved HSV gB and gH null mutants that could potentially also possess gross defects in the virion envelope. Here, we produced recombinant HSV-expressing mutant forms of gB with single amino acid substitutions in the hydrophobic “fusion loops.” These fusion loops are thought to play a direct role in membrane fusion by insertion into cellular membranes. HSV recombinants expressing gB with any one of four fusion loop mutations (W174R...

Herpes Simplex Virus 1 UL47 Interacts with Viral Nuclear Egress Factors UL31, UL34, and Us3 and Regulates Viral Nuclear Egress

Liu, Zhuoming; Kato, Akihisa; Shindo, Keiko; Noda, Takeshi; Sagara, Hiroshi; Kawaoka, Yoshihiro; Arii, Jun; Kawaguchi, Yasushi
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /05/2014 EN
Relevância na Pesquisa
16.37%
Herpesviruses have evolved a unique mechanism for nuclear egress of nascent progeny nucleocapsids: the nucleocapsids bud through the inner nuclear membrane into the perinuclear space between the inner and outer nuclear membranes (primary envelopment), and enveloped nucleocapsids then fuse with the outer nuclear membrane to release nucleocapsids into the cytoplasm (de-envelopment). We have shown that the herpes simplex virus 1 (HSV-1) major virion structural protein UL47 (or VP13/VP14) is a novel regulator for HSV-1 nuclear egress. In particular, we demonstrated the following: (i) UL47 formed a complex(es) with HSV-1 proteins UL34, UL31, and/or Us3, which have all been reported to be critical for viral nuclear egress, and these viral proteins colocalized at the nuclear membrane in HSV-1-infected cells; (ii) the UL47-null mutation considerably reduced primary enveloped virions in the perinuclear space although capsids accumulated in the nucleus; and (iii) UL47 was detected in primary enveloped virions in the perinuclear space by immunoelectron microscopy. These results suggested that UL47 promoted HSV-1 primary envelopment, probably by interacting with the critical HSV-1 regulators for viral nuclear egress and by modulating their functions.

Color Image Segmentation Based on Different Color Space Models Using Automatic GrabCut

Khattab, Dina; Ebied, Hala Mousher; Hussein, Ashraf Saad; Tolba, Mohamed Fahmy
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
25.96%
This paper presents a comparative study using different color spaces to evaluate the performance of color image segmentation using the automatic GrabCut technique. GrabCut is considered as one of the semiautomatic image segmentation techniques, since it requires user interaction for the initialization of the segmentation process. The automation of the GrabCut technique is proposed as a modification of the original semiautomatic one in order to eliminate the user interaction. The automatic GrabCut utilizes the unsupervised Orchard and Bouman clustering technique for the initialization phase. Comparisons with the original GrabCut show the efficiency of the proposed automatic technique in terms of segmentation, quality, and accuracy. As no explicit color space is recommended for every segmentation problem, automatic GrabCut is applied with RGB, HSV, CMY, XYZ, and YUV color spaces. The comparative study and experimental results using different color images show that RGB color space is the best color space representation for the set of the images used.

Interleukin-1α released from HSV-1 infected keratinocytes acts as a functional alarmin in the skin

Milora, Katelynn A.; Miller, Samantha L.; Sanmiguel, Julio C.; Jensen, Liselotte E.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 17/10/2014 EN
Relevância na Pesquisa
26.26%
Herpes simplex virus-1 (HSV-1) is a human pathogen that utilizes several strategies to circumvent the host immune response. An immune evasion mechanism employed by HSV-1 is retention of interleukin-1β (IL-1β) in the intracellular space, which blocks the pro-inflammatory activity of IL-1β. Here, we report that HSV-1 infected keratinocytes actively release the also pro-inflammatory IL-1α, preserving the ability of infected cells to signal danger to the surrounding tissue. The extracellular release of IL-1α is independent of inflammatory caspases. In vivo recruitment of leukocytes to early HSV-1 micro-infection sites within the epidermis is dependent upon IL-1 signalling. Following cutaneous HSV-1 infection, mice unable to signal via extracellular IL-1α exhibit an increased mortality rate associated with viral dissemination. We conclude that IL-1α acts as an alarmin essential for leukocyte recruitment and protective immunity against HSV-1. This function may have evolved to counteract an immune evasion mechanism deployed by HSV-1.

Herpes Simplex Virus 1 Us3 Deletion Mutant is Infective Despite Impaired Capsid Translocation to the Cytoplasm

Wild, Peter; Leisinger, Sabine; de Oliveira, Anna Paula; Schraner, Elisabeth M.; Kaech, Andres; Ackermann, Mathias; Tobler, Kurt
Fonte: MDPI Publicador: MDPI
Tipo: Artigo de Revista Científica
Publicado em 12/01/2015 EN
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16.29%
Herpes simplex virus 1 (HSV-1) capsids are assembled in the nucleus bud at the inner nuclear membrane into the perinuclear space, acquiring envelope and tegument. In theory, these virions are de-enveloped by fusion of the envelope with the outer nuclear membrane and re-enveloped by Golgi membranes to become infective. Us3 enables the nucleus to cytoplasm capsid translocation. Nevertheless, Us3 is not essential for the production of infective progeny viruses. Determination of phenotype distribution by quantitative electron microscopy, and calculation per mean nuclear or cell volume revealed the following: (i) The number of R7041(∆US3) capsids budding at the inner nuclear membrane was significantly higher than that of wild type HSV-1; (ii) The mean number of R7041(∆US3) virions per mean cell volume was 2726, that of HSV-1 virions 1460 by 24 h post inoculation; (iii) 98% of R7041(∆US3) virions were in the perinuclear space; (iv) The number of R7041(∆US3) capsids in the cytoplasm, including those budding at Golgi membranes, was significantly reduced. Cell associated R7041(∆US3) yields were 2.37 × 108 and HSV-1 yields 1.57 × 108 PFU/mL by 24 h post inoculation. We thus conclude that R7041(∆US3) virions, which acquire envelope and tegument by budding at the inner nuclear membrane into the perinuclear space...

3D visualization of an invariant display strategy for hyperspecteral imagery; Three-dimensional visualization of an invariant display strategy for hyperspecteral imagery

Kim, Kang Suk
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xvi, 88 p. : ill. (some col.)
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Approved for public release, distribution is unlimited; Spectral Imagery provides multi-dimensional data, which are difficult to display in standard three-color image formats. Tyo, et al. (2001) propose an invariant display strategy to address this problem. This approach is to mimic the dynamics of human perception. The dimensionality of the data are reduced by using a Principal Component (PC) transformation, and then displayed by making used of a Hue, Saturation, and Value (HSV) display transform. This study addresses the PC transformation strategy , looks for a global eigenvector via 3D visualization of HSV color space information, and examines the suggested algorithm to provide the most intuitive display. The user interface created in this thesis is capable of computing the necessary implementation of the proposed strategy, viewing selected Region of Interest (ROI) in HSV color space model in 3D, and viewing the 2D resultant image. A demonstration application uses Java language including Java2D, Xj3D Player, Document Object Model (DOM) Application Program Interfaces (API), and Extensible 3D Language (X3D). The Java2D API enables the user to load imagery, process data, and render results in a two-dimensional (2D) view. Xj3D and DOM APIs are introduced to visualize Tyo's invariant display strategy in three-dimensional (3D) views and then to save results as X3D scenes. These techniques appear to be inherently valuable and can serve as the basis for further research. Through this thesis...

Comparing the Performance of L*A*B* and HSV Color Spaces with Respect to Color Image Segmentation

Bora, Dibya Jyoti; Gupta, Anil Kumar; Khan, Fayaz Ahmad
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 04/06/2015
Relevância na Pesquisa
26.18%
Color image segmentation is a very emerging topic for image processing research. Since it has the ability to present the result in a way that is much more close to the human yes perceive, so todays more research is going on this area. Choosing a proper color space is a very important issue for color image segmentation process. Generally LAB and HSV are the two frequently chosen color spaces. In this paper a comparative analysis is performed between these two color spaces with respect to color image segmentation. For measuring their performance, we consider the parameters: mse and psnr . It is found that HSV color space is performing better than LAB.; Comment: 11 pages, 19 figures in International Journal of Emerging Technology and Advanced Engineering,Volume 5, Issue 2, February 2015

On fields inspired with the polar HSV -- RGB theory of Colour

Haluška, Ján
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 30/11/2015
Relevância na Pesquisa
25.98%
A three-polar, cf. T. Gregor, J. Halu\v{s}ka, Lexicographical ordering and field operations in the complex plane. Stud. Mat. 41(2014), 123--133., $HSV-RGB$ Colour space $\triangle$ was introduced and studied. It was equipped with operations of addition, subtraction, multiplication, and (partially) division. Achromatic Grey Hues form an ideal $\mathfrak{S}$. Factorizing $\triangle$ by the ideal $\mathfrak{S}$, we obtain a field $\triangle | \mathfrak{S}$. An element (i.e an individual Colour) in $\triangle | \mathfrak{S}$ is a triplet of three triangular coefficients. The set of all triangular coefficients is a subset of a semi-field of parabolic-complex functions. For the parabolic-complex number set, cf.~A. A. Harkin--J. B. Harkin, Geometry of general complex numbers. Mathematics magazine, 77(2004), 118--129.; Comment: in Press, in book: Jacek Hejduk, Stanis{\l}aw Kowalczyk, Ryszard J. Pawlak and Ma{\l}gorzata Turowska(eds.): Modern Real Analysis, Chapt. 6, Lodz University Press, Lodz 2015, pp. 69--88

A Second Order TV-type Approach for Inpainting and Denoising Higher Dimensional Combined Cyclic and Vector Space Data

Bergmann, Ronny; Weinmann, Andreas
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
25.93%
In this paper we consider denoising and inpainting problems for higher dimensional combined cyclic and linear space valued data. These kind of data appear when dealing with nonlinear color spaces such as HSV, and they can be obtained by changing the space domain of, e.g., an optical flow field to polar coordinates. For such nonlinear data spaces, we develop algorithms for the solution of the corresponding second order total variation (TV) type problems for denoising, inpainting as well as the combination of both. We provide a convergence analysis and we apply the algorithms to concrete problems.; Comment: revised submitted version

Novel and Tuneable Method for Skin Detection Based on Hybrid Color Space and Color Statistical Features

Azad, Reza; Shayegh, Hamid Reza
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 24/07/2014
Relevância na Pesquisa
25.78%
Skin detection is one of the most important and primary stages in some of image processing applications such as face detection and human tracking. So far, many approaches are proposed to done this case. Near all of these methods have tried to find best match intensity distribution with skin pixels based on popular color spaces such as RGB, CMYK or YCbCr. Results show these methods cannot provide an accurate approach for every kinds of skin. In this paper, an approach is proposed to solve this problem using statistical features technique. This approach is including two stages. In the first one, from pure skin statistical features were extracted and at the second stage, the skin pixels are detected using HSV and YCbCr color spaces. In the result part, the proposed approach is applied on FEI database and the accuracy rate reached 99.25 + 0.2. Further proposed method is applied on complex background database and accuracy rate obtained 95.40+0.31%. The proposed approach can be used for all kinds of skin using train stage which is the main advantages of it. Low noise sensitivity and low computational complexity are some of other advantages.; Comment: 2013 First International Conference on computer, Information Technology and Digital Media. arXiv admin note: substantial text overlap with arXiv:1407.6318

Hand Pointing Detection Using Live Histogram Template of Forehead Skin

Tofighi, Ghassem; Afarin, Nasser Ali; Raahemifar, Kamraan; Venetsanopoulos, Anastasios N.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 18/07/2014
Relevância na Pesquisa
25.88%
Hand pointing detection has multiple applications in many fields such as virtual reality and control devices in smart homes. In this paper, we proposed a novel approach to detect pointing vector in 2D space of a room. After background subtraction, face and forehead is detected. In the second step, forehead skin H-S plane histograms in HSV space is calculated. By using these histogram templates of users skin, and back projection method, skin areas are detected. The contours of hand are extracted using Freeman chain code algorithm. Next step is finding fingertips. Points in hand contour which are candidates for the fingertip can be found in convex defects of convex hull and contour. We introduced a novel method for finding the fingertip based on the special points on the contour and their relationships. Our approach detects hand-pointing vectors in live video from a common webcam with 94%TP and 85%TN.; Comment: Accepted for oral presentation in DSP2014