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1.
Artigo em Inglês | MEDLINE | ID: mdl-36197859

RESUMO

As person parts are frequently misaligned between detected human boxes, an image representation that can handle this part misalignment is required. In this work, we propose an effective grouped attentive re-identification (GAReID) framework to learn part-aligned and background robust representations for person re-identification (ReID). Specifically, the GAReID framework consists of grouped high-order pooling (GHOP) and attentive high-order pooling (AHOP) layers, which generate high-order image and foreground features, respectively. In addition, a novel grouped Kronecker product (GKP) is proposed to use both channel group and shuffle strategies for high-order feature compression, while promoting the representational capabilities of compressed high-order features. We show that our method derives from an interpretable motivation and elegantly reduces part misalignments without using landmark detection or feature partition. This article theoretically and experimentally demonstrates the superiority of the GAReID framework, achieving state-of-the-art performance on various person ReID datasets.

2.
J Speech Lang Hear Res ; 64(9): 3685-3696, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34407380

RESUMO

Purpose During insertion of the cochlear implant electrode array, the tip of the array may fold back on itself and can cause serious complications to patients. This article presents a sensing system for cochlear implantation in a cochlear model. The electrode array fold-over behaviors can be detected by analyzing capacitive information from the array tip. Method Depending on the angle of the array tip against the cochlear inner wall when it enters the cochlear model, different insertion patterns of the electrode array could occur, including smooth insertion, buckling, and fold-over. The insertion force simulating the haptic feedback for surgeons and bipolar capacitance signals during the insertion progress were collected and compared. The Pearson correlation coefficient (PCC) was applied to the collected capacitive signals to discriminate the fold-over pattern. Results Forty-six electrode array insertions were conducted and the deviation of the measured insertion force varies between a range of 20% and 30%. The capacitance values from electrode pair (1, 2) were recorded for analyzing. A threshold for the PCC is set to be 0.94 that can successfully discriminate the fold over insertions from the other two types of insertions, with a success rate of 97.83%. Conclusions Capacitive measurement is an effective method for the detection of faulty insertions and the maximization of the outcome of cochlear implantation. The proposed capacitive sensing system can be used in other tissue implants in vessels, spinal cord, or heart.


Assuntos
Implante Coclear , Implantes Cocleares , Cóclea , Eletrodos Implantados , Humanos
3.
IEEE Trans Image Process ; 30: 2908-2922, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33560985

RESUMO

Despite the remarkable progress in recent years, person Re-Identification (ReID) approaches frequently fail in cases where the semantic body parts are misaligned between the detected human boxes. To mitigate such cases, we propose a novel High-Order ReID (HOReID) framework that enables semantic pose alignment by aggregating the fine-grained part details of multilevel feature maps. The HOReID adopts a high-order mapping of multilevel feature similarities in order to emphasize the differences of the similarities between aligned and misaligned part pairs in two person images. Since the similarities of misaligned part pairs are reduced, the HOReID enhances pose-robustness within the learned features. We show that our method derives from an intuitive and interpretable motivation and elegantly reduces the misalignment problem without using any prior knowledge from human pose annotations or pose estimation networks. This paper theoretically and experimentally demonstrates the effectiveness of the proposed HOReID, achieving superior performance over the state-of-the-art methods on the four large-scale person ReID datasets.


Assuntos
Identificação Biométrica/métodos , Aprendizado Profundo , Processamento de Imagem Assistida por Computador/métodos , Postura/fisiologia , Algoritmos , Bases de Dados Factuais , Humanos , Semântica
4.
Artigo em Inglês | MEDLINE | ID: mdl-25167151

RESUMO

Ultrasonic guided waves can be used to assess and monitor long elements of a structure from a single position. The greatest challenges for any guided wave system are the plethora of wave modes arising from the geometry of the structural element which propagate with a range of frequency-dependent velocities and the interpretation of these combined signals reflected by discontinuities in the structural element. In this paper, a novel signal processing technique is presented using a combination of frequency-sweep measurement, sampling rate conversion, and Fourier transform. The technique is applied to synthesized and experimental data to identify different modes in complex ultrasonic guided wave signals. It is demonstrated throughout the paper that the technique also has the capability to derive the time of flight and group velocity dispersion curve of different wave modes in field inspections.

5.
IEEE Trans Image Process ; 22(11): 4560, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24057007

RESUMO

In a previous paper, Chang et al. presented a method for iterative decoding of FEC-based multiple description codes in image transmission. In this correspondence, we clarify that an outer interleaver used in the above research was previously proposed for the iterative decoding and optimization of product codes in image transmission.

6.
IEEE Trans Image Process ; 22(9): 3636-47, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23751961

RESUMO

We propose a new gait recognition method that combines holistic and model-based features. Both types of features are extracted automatically from gait silhouette sequences and their combination takes place by means of a pair of hidden Markov models. In the proposed system, the holistic features are initially used for capturing general gait dynamics whereas, subsequently, the model-based features are deployed for capturing more detailed sub-dynamics by refining upon the preceding general dynamics. Furthermore, the holistic and model-based features are suitably processed in order to improve the discriminatory capacity of the final system. The experimental results show that the proposed method exhibits performance advantages in comparison with popular existing methods.


Assuntos
Marcha/fisiologia , Modelos Biológicos , Reconhecimento Automatizado de Padrão/métodos , Gravação em Vídeo/métodos , Algoritmos , Fenômenos Biomecânicos , Cabeça/fisiologia , Humanos , Perna (Membro)/fisiologia , Cadeias de Markov , Postura/fisiologia , Tronco/fisiologia , Caminhada/fisiologia
7.
IEEE Trans Image Process ; 21(4): 2256-68, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22194243

RESUMO

In this paper, we present a novel and efficient gait recognition system. The proposed system uses two novel gait representations, i.e., the shifted energy image and the gait structural profile, which have increased robustness to some classes of structural variations. Furthermore, we introduce a novel method for the simulation of walking conditions and the generation of artificial subjects that are used for the application of linear discriminant analysis. In the decision stage, the two representations are fused. Thorough experimental evaluation, conducted using one traditional and two new databases, demonstrates the advantages of the proposed system in comparison with current state-of-the-art systems.


Assuntos
Algoritmos , Inteligência Artificial , Marcha/fisiologia , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Técnica de Subtração , Imagem Corporal Total/métodos , Humanos , Aumento da Imagem/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
IEEE Trans Image Process ; 16(3): 731-40, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17357733

RESUMO

A new feature extraction process is proposed for gait representation and recognition. The new system is based on the Radon transform of binary silhouettes. For each gait sequence, the transformed silhouettes are used for the computation of a template. The set of all templates is subsequently subjected to linear discriminant analysis and subspace projection. In this manner, each gait sequence is described using a low-dimensional feature vector consisting of selected Radon template coefficients. Given a test feature vector, gait recognition and verification is achieved by appropriately comparing it to feature vectors in a reference gait database. By using the new system on the Gait Challenge database, very considerable improvements in recognition performance are seen in comparison to state-of-the-art methods for gait recognition.


Assuntos
Algoritmos , Inteligência Artificial , Biometria/métodos , Marcha/fisiologia , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Imagem Corporal Total/métodos , Simulação por Computador , Análise Discriminante , Humanos , Aumento da Imagem/métodos , Modelos Lineares , Modelos Biológicos , Modelos Estatísticos , Análise Numérica Assistida por Computador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador , Técnica de Subtração
9.
IEEE Trans Image Process ; 15(8): 2113-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16900669

RESUMO

We propose a novel scheme for error-resilient image transmission. The proposed scheme employs a product coder consisting of low-density parity check (LDPC) codes and Reed-Solomon codes in order to deal effectively with bit errors. The efficiency of the proposed scheme is based on the exploitation of determinate symbols in Tanner graph decoding of LDPC codes and a novel product code optimization technique based on error estimation. Experimental evaluation demonstrates the superiority of the proposed system in comparison to recent state-of-the-art techniques for image transmission.


Assuntos
Artefatos , Redes de Comunicação de Computadores , Compressão de Dados/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Processamento de Sinais Assistido por Computador , Algoritmos , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
IEEE Trans Image Process ; 15(1): 54-67, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16435536

RESUMO

The transmission of JPEG2000 images over wireless channels is examined using reorganization of the compressed images into error-resilient, product-coded streams. The product-code consists of Turbo-codes and Reed-Solomon codes which are optimized using an iterative process. The generation of the stream to be transmitted is performed directly using compressed JPEG2000 streams. The resulting scheme is tested for the transmission of compressed JPEG2000 images over wireless channels and is shown to outperform other algorithms which were recently proposed for the wireless transmission of images.


Assuntos
Algoritmos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Armazenamento e Recuperação da Informação/métodos , Processamento de Sinais Assistido por Computador , Telecomunicações , Gravação em Vídeo/métodos , Redes de Comunicação de Computadores , Gráficos por Computador , Análise Numérica Assistida por Computador
11.
IEEE Trans Image Process ; 14(11): 1890-901, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16279187

RESUMO

A novel image transmission scheme is proposed for the communication of set partitioning in hierarchical trees image streams over wireless channels. The proposed scheme employs turbo codes and Reed-Solomon codes in order to deal effectively with burst errors. An algorithm for the optimal unequal error protection of the compressed bitstream is also proposed and applied in conjunction with an inherently more efficient technique for product code decoding. The resulting scheme is tested for the transmission of images over wireless channels. Experimental evaluation clearly demonstrates the superiority of the proposed transmission system in comparison to well-known robust coding schemes.


Assuntos
Algoritmos , Redes de Comunicação de Computadores , Compressão de Dados/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Processamento de Sinais Assistido por Computador , Telecomunicações
12.
IEEE Trans Image Process ; 11(3): 234-42, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-18244627

RESUMO

A method is presented for the optimization of arbitrary quantizers by use of a compensating postfilter. It is shown that the resulting optimized quantizers fit the model of a linear time-invariant filter followed by additive noise uncorrelated with the input which also characterizes the optimal (Lloyd-Max) quantizers. On the basis of this model, an expression for the variance of the error of a subband coder using optimized quantizers is explicitly determined. Given analysis filters which statistically separate the subbands, it is shown that this variance is minimized if these synthesis filters are chosen, which would achieve perfect reconstruction in lossless coding. The globally optimum filter bank, minimizing the coder error variance, is further obtained by proper choice of its analysis filters. A novel method for the determination of optimal bit allocation to subbands of the filter banks with optimized quantizers is also developed. The results are evaluated experimentally by comparison of the optimum uniformly split subband image coding scheme to classical logarithmically-split filter bank (wavelet) coding methods.

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