10 research outputs found

    Face Detection Using Randomized Hough Transform (RHT) with Various Ellipses Segmentations

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    Face detection is one of earlier phase in face recognition process. This research aims to get the faces area on digital image without being affected by face orientation, lights condition, background and the expression. The detected face area is usually shaped by a rectangle. Many pixels on the rectangle are not part of face, especially at the four of the image corners. This research use an ellipse as replacement a rectangle. The detected face is shaped by ellipses with various sizes and orientations. The digital image segmentations is used to detect face candidates area. The ellipse is formed by using Randomized Hough Transform (RHT) method, which is influenced by the center point of ellipse candidates. RHT found three random pixels on segmented image. The rate of success of RHT is determined by segmentation results. The research result is tested by using various thresholds, and get the best accuracy at 74.4%. The rate of accuracy is measured by comparing between RHT ellipses shape and circle shape on OpenCV library as ground truth

    An Automatic Face Detection System for RGB Images

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    We propose a robust face detection approach that works for digital color images. Our automatic detection method is based on image skin regions, therefore a skin-based segmentation of RGB images is provided first. Then, we decide for each skin region if it represents a human face or not, using a set of candidate criteria, an edge detection process, a correlation based technique and a threshold-based method. A high face detection rate is obtained using the proposed method

    FACE LOCALIZATION AND DETECTION BASED ON SYMMETRY DETECTION AND TEXTURE FEATURES

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    Predefined pattern detection in large time series

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    Predefined pattern detection from time series is an interesting and challenging task. In order to reduce its computational cost and increase effectiveness, a number of time series representation methods and similarity measures have been proposed. Most of the existing methods focus on full sequence matching, that is, sequences with clearly defined beginnings and endings, where all data points contribute to the match. These methods, however, do not account for temporal and magnitude deformations in the data and result to be ineffective on several real-world scenarios where noise and external phenomena introduce diversity in the class of patterns to be matched. In this paper, we present a novel pattern detection method, which is based on the notions of templates, landmarks, constraints and trust regions. We employ the Minimum Description Length (MDL) principle for time series preprocessing step, which helps to preserve all the prominent features and prevents the template from overfitting. Templates are provided by common users or domain experts, and represent interesting patterns we want to detect from time series. Instead of utilising templates to match all the potential subsequences in the time series, we translate the time series and templates into landmark sequences, and detect patterns from landmark sequence of the time series. Through defining constraints within the template landmark sequence, we effectively extract all the landmark subsequences from the time series landmark sequence, and obtain a number of landmark segments (time series subsequences or instances). We model each landmark segment through scaling the template in both temporal and magnitude dimensions. To suppress the influence of noise, we introduce the concept oftrust region, which not only helps to achieve an improved instance model, but also helps to catch the accurate boundaries of instances of the given template. Based on the similarities derived from instance models, we introduce the probability density function to calculate a similarity threshold. The threshold can be used to judge if a landmark segment is a true instance of the given template or not. To evaluate the effectiveness and efficiency of the proposed method, we apply it to two real-world datasets. The results show that our method is capable of detecting patterns of temporal and magnitude deformations with competitive performance

    Geometrical-based lip-reading using template probabilistic multi-dimension dynamic time warping

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    By identifying lip movements and characterizing their associations with speech sounds, the performance of speech recognition systems can be improved, particularly when operating in noisy environments. In this paper, we present a geometrical-based automatic lip reading system that extracts the lip region from images using conventional techniques, but the contour itself is extracted using a novel application of a combination of border following and convex hull approaches. Classification is carried out using an enhanced dynamic time warping technique that has the ability to operate in multiple dimensions and a template probability technique that is able to compensate for differences in the way words are uttered in the training set. The performance of the new system has been assessed in recognition of the English digits 0 to 9 as available in the CUAVE database. The experimental results obtained from the new approach compared favorably with those of existing lip reading approaches, achieving a word recognition accuracy of up to 71% with the visual information being obtained from estimates of lip height, width and their ratio

    Scale And Pose Invariant Real-time Face Detection And Tracking

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    Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2008Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2008Bu çalışmada görüntü tabanlı en gözde ve en yeni yöntemlerden biri olan ve Adaboost algoritması, “Integral Görüntü” tekniği ve kaskat sınıflandırıcılara dayalı yöntem kullanılarak insan yüzünün bulunması ve izlenmesi gerçeklendi. Beş değişik poza (sol, sol+45°, ön yüz, sağ+45° ve sağ) ait insan yüzü bu yöntemle eğitildi. Ayrıca, kolay uygulanabilirliğinden ve gerçek zamanlı uygulamalardaki hızından dolayı, yüzün izlenmesi için CAMSHIFT algoritması kullanıldı. Görüntü işlemenin gerçek zamanlı uygulamalara kötü yöndeki etkisinden kaçınmak için paralel programlama gerçeklendi. Bunu sağlamak için iki iplikçik (ana ve çocuk) oluşturuldu. Çocuk iplikçik alınan görüntü çerçeveleri üzerinde yüzleri bulmaya çalışırken, ana iplikçik de gelen tüm görüntüleri çoçuk iplikçikten aldığı veriye göre işler ve bunu kullanıcı penceresine basar. Sonuç olarak, insan yüzlerini bulma ve izleme sistemi başarılı bi gerçeklendi ve üç farklı test kümesi ile bir video kümesindeki test sonuçlarına göre yüksek başarım oranı sağladığı görüldü.In this study, one of the most popular and recent appearance based face detection method used which is a combination of Adaboost algorithm, Integral Image and cascading classifiers. Faces are trained for five different poses (left, left+45°, front, right+45° and right). Also, CAMSHIFT algorithm is used for face tracking because of its speed and easy implementation for face. To avoid impact of image analysis’s computations on Real-time application, parallel processing methods were used. Two processes (main and child) were created for this purpose. Child process detects faces periodically on the given frame while the main one process all frames and displays the results of child process to the user screen. In conclusion, our face detection and tracking system has been implemented successfully and it has demonstrated significantly high detection/tracking rates based on the tests on three different image databases and one video database.Yüksek LisansM.Sc

    A Computer Vision Story on Video Sequences::From Face Detection to Face Super- Resolution using Face Quality Assessment

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    Robust object detection in the wild via cascaded DCGAN

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    This research deals with the challenges of object detection at a distance or low resolution in the wild. The main intention of this research is to exploit and cascade state-of-the-art models and propose a new framework for enabling successful deployment for diverse applications. Specifically, the proposed deep learning framework uses state-of-the-art deep networks, such as Deep Convolutional Generative Adversarial Network (DCGAN) and Single Shot Detector (SSD). It combines the above two deep learning models to generate a new framework, namely DCGAN-SSD. The proposed model can deal with object detection and recognition in the wild with various image resolutions and scaling differences. To deal with multiple object detection tasks, the training of this network model in this research has been conducted using different cross-domain datasets for various applications. The efficiency of the proposed model can further be determined by the validation of diverse applications such as visual surveillance in the wild in intelligent cities, underwater object detection for crewless underwater vehicles, and on-street in-vehicle object detection for driverless vehicle technologies. The results produced by DCGAN-SSD indicate that the proposed method in this research, along with Particle Swarm Optimization (PSO), outperforms every other application concerning object detection and demonstrates its great superiority in improving object detection performance in diverse testing cases. The DCGAN-SSD model is equipped with PSO, which helps select the hyperparameter for the object detector. Most object detectors struggle in this regard, as they require manual effort in selecting the hyperparameters to obtain better object detection. This research encountered the problem of hyperparameter selection through the integration of PSO with SSD. The main reason the research conducted with deep learning models was the traditional machine learning models lag in accuracy and performance. The advantage of this research and it is achieved with the integration of DCGAN-SSD has been accommodated under a single pipeline

    Structural health monitoring meets data mining

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    With the development of sensing and data processing techniques, monitoring physical systems in the field with a sensor network is becoming a feasible option for many domains. Such monitoring systems are referred to as Structural Health Monitoring (SHM) systems. By definition, SHM is the process of implementing a damage detection and characterisation strategy for engineering structures, which involves data collection, damage-sensitive feature extraction and statistical analysis. Most of the SHM process can be addressed by techniques from the Data Mining domain, so I conduct this research by combining these two fields. The monitoring system employed in this research is a sensor network installed on a Dutch highway bridge, which aims to monitor dynamic health aspects of the bridge and its long-term degradation. I have explored the specific focus of each sensor type under multiple scales, and analysed the dependencies between sensor types. Based on landmarks and constraints, I have proposed a novel predefined pattern detection method to select traffic events for modal analysis. I have analysed the influence of temperature and traffic mass on natural frequencies, and verified that natural frequencies decrease with temperature increases, but the influence of traffic mass is weaker than that of temperature.Chinese CSC Dutch STWAlgorithms and the Foundations of Software technolog
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