F. J. Díaz-Pernas
University of Valladolid
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by F. J. Díaz-Pernas.
Computer Methods and Programs in Biomedicine | 2014
D. González-Ortega; F. J. Díaz-Pernas; Mario Martínez-Zarzuela; M. Antón-Rodríguez
In this paper, a 3D computer vision system for cognitive assessment and rehabilitation based on the Kinect device is presented. It is intended for individuals with body scheme dysfunctions and left-right confusion. The system processes depth information to overcome the shortcomings of a previously presented 2D vision system for the same application. It achieves left and right-hand tracking, and face and facial feature detection (eye, nose, and ears) detection. The system is easily implemented with a consumer-grade computer and an affordable Kinect device and is robust to drastic background and illumination changes. The system was tested and achieved a successful monitoring percentage of 96.28%. The automation of the human body parts motion monitoring, its analysis in relation to the psychomotor exercise indicated to the patient, and the storage of the result of the realization of a set of exercises free the rehabilitation experts of doing such demanding tasks. The vision-based system is potentially applicable to other tasks with minor changes.
Neurocomputing | 2009
M. Antón-Rodríguez; F. J. Díaz-Pernas; J. F. Díez-Higuera; Mario Martínez-Zarzuela; D. González-Ortega; D. Boto-Giralda
The aim of this paper is to outline a multiple scale neural model to recognise colour images of textured scenes. This model combines colour and textural information in order to recognise colour texture images through the operation of two main components: a segmentation component composed of the colour opponent system (COS) and the chromatic segmentation system (CSS); and a recognition component formed by an ARTMAP-based neural network with scale and orientation-invariance properties. Segmentation is achieved by perceptual contour extraction and diffusion processes on the colour opponent channels based on the human psychophysical theory of colour perception. This colour regions enhancement along with their local textural features constitutes the recognition pattern to be sent to the supervised neural classifier. The CSS accomplishes the colour region enhancement through a multiple scale loop of oriented filters and competition-cooperation mechanisms. Afterwards, the neural architecture performs an attentive recognition of the scene using those oriented filters responses and the chromatic diffusions. Some comparative tests with other models are included in order to prove the recognition capabilities of this neural architecture and how the use of colour information encourages the texture classification and the accuracy of the boundary detection.
international conference on informatics in control, automation and robotics | 2008
D. Boto-Giralda; M. Antón-Rodríguez; F. J. Díaz-Pernas; J. F. Díez-Higuera
In this chapter, a neural network model is presented for forecasting the average speed values at highway traffic detectors locations using the Fuzzy ARTMAP theory. The performance of the model is measured by the deviation between the speed values provided by the loop detectors and the predicted speed values. Different Fuzzy ARTMAP configuration cases are analysed in their training and testing phases. Some ad-hoc mechanisms added to the basic Fuzzy ARTMAP structure are also described to improve the entire model performance. The achieved results make this model suitable for being implemented on advanced traffic management systems (ATMS) and advanced traveller information system (ATIS).
Journal of Network and Computer Applications | 2010
D. González-Ortega; F. J. Díaz-Pernas; Mario Martínez-Zarzuela; M. Antón-Rodríguez; J. F. Díez-Higuera; D. Boto-Giralda
In this paper, a marker-free computer vision system for cognitive rehabilitation tests monitoring is presented. The system monitors and analyzes the correct and incorrect realization of a set of psicomotricity exercises in which a hand has to touch a facial feature. The monitoring requires different human body parts detection and tracking. Detection of face, eyes, nose, and hands is achieved with a set of classifiers built independently based on the AdaBoost algorithm. Comparisons with other detection approaches, regarding performance and applicability to the monitoring system, are presented. Face and hands tracking is accomplished through the CAMShift algorithm with independent and adaptive two-dimensional histograms of the chromaticity components of the TSL color space for the pixels inside these three regions. The TSL color space was selected after a study of five color spaces regarding skin color characterization. The system is easily implemented with a consumer-grade computer and a camera, unconstrained background and illumination and runs at more than 23 frames per second. The system was tested and achieved a successful monitoring percentage of 97.62%. The automation of the human body parts motion monitoring, its analysis in relation to the psicomotricity exercise indicated to the patient and the storage of the result of the realization of a set of exercises free the rehabilitation experts of doing such demanding tasks. The vision-based system is potentially applicable to other human-computer interface tasks with minor changes.
international work-conference on the interplay between natural and artificial computation | 2011
Mario Martínez-Zarzuela; F. J. Díaz-Pernas; M. Antón-Rodríguez; F. Perozo-Rondón; D. González-Ortega
Face detection is a time consuming task in computer vision applications. In this article, an approach for AdaBoost face detection using Haar-like features on the GPU is proposed. The GPU adapted version of the algorithm manages to speed-up the detection process when compared with the detection performance of the CPU using a well-known computer vision library. An overall speed-up of × 3.3 is obtained on the GPU for video resolutions of 640×480 px when compared with the CPU implementation. Moreover, since the CPU is idle during face detection, it can be used simultaneously for other computer vision tasks.
VISUAL'05 Proceedings of the 8th international conference on Visual Information and Information Systems | 2005
D. González-Ortega; F. J. Díaz-Pernas; J. F. Díez-Higuera; Mario Martínez-Zarzuela; D. Boto-Giralda
In this paper we present a computer vision architecture to detect and track the face and hands of a human being in real time from a video sequence captured by a webcam. The architecture has a first preprocessing stage, including a color filtering module, a motion filtering module, a color-based segmentation, a processing channels merge module and, finally, a contour search and discrimination module. The aim of the first stage is to discard the image regions which are highly unlikely to correspond with skin. Thus, the second stage of the architecture is a previously trained Fuzzy ARTMAP multiscale neural network module which only processes those image regions selected by the preprocessing stage, which are fully expected to be skin. The neural networks make the last decision about face and hand detection. After that, the architecture tracks the trajectories which face and hands follow.
International Journal of Knowledge Society Research | 2012
M. Antón-Rodríguez; M. A. Pérez-Juárez; F. J. Díaz-Pernas; F.J. Perozo-Rondón; Mario Martínez-Zarzuela; D. González-Ortega
New educational trends demand learning processes that fulfill the requirements and interests of students. In this sense, developing new activities focused on specific themes for the open source e-learning platform Moodle, provides the added value of offering their integrated use in the learning environment. Basing on this assumption, Moodle applications for checking JavaScript and PHP codes have been developed, allowing improving the learning process in web programming University courses. These applications offer the students information about the committed errors and about the key terms of the programming language. Moreover, they also gather information about the type of errors committed by each student so that the teacher can graphically observe which concepts are more problematic and need to be clarified. The paper also describes the result of a qualitative analysis of its use in several courses offered in study programmes of the University of Valladolid.
international work conference on the interplay between natural and artificial computation | 2009
F. J. Díaz-Pernas; M. Antón-Rodríguez; J. F. Díez-Higuera; Mario Martínez-Zarzuela; D. González-Ortega; D. Boto-Giralda
This paper presents a supervised neural architecture, called SOON, for texture classification. Multi-scale Gabor filtering is used to extract the textural features which shape the input to a neural classifier with orientation invariance properties in order to accomplish the classification. Three increasing complexity tests over the well-known Brodatz database are performed to quantify its behavior. The test simulations, including the entire texture album classification, show the stability and robustness of the SOON response.
intelligent data engineering and automated learning | 2009
D. González-Ortega; F. J. Díaz-Pernas; Mario Martínez-Zarzuela; M. Antón-Rodríguez; J. F. Díez-Higuera; D. Boto-Giralda
In this paper we present a fast and robust nose detection and tracking application which runs on a consumer-grade computer with video input from an inexpensive Universal Serial Bus camera. Nose detection is based on the AdaBoost algorithm with Haar-like features. A detailed study was developed to select the positive and negative training samples and the parameters of the detector. Pyramidal Lucas-Kanade optical flow tracking algorithm is applied to the nostrils from a previous nose detection in a frame of a video sequence. Tracking takes 2 ms and is robust to different face positions, backgrounds and illumination. The nose detection and tracking application can be used alone or integrated in a hand-free vision-based Human-Computer Interface.
Applications of Artificial Neural Networks in Image Processing | 1996
J. F. Díez-Higuera; F. J. Díaz-Pernas; Juan Lopez-Coronado
We are interested in designing a neural network system for automatic chromosome. The goal of this approach is to make the chromosome regions more salient and more interpretable to human skilled technicians than they are in the original imagery. The proposed segmentation model is based upon the biologically derived boundary contour system (BCS) of Grossberg and Mingolla. The practical application of the model to real images raises an important problem. The boundaries generated by BCS have a sizable thickness that is a function of the contrast gradient between two adjacent regions. In order to solve this problem we propose the use of a feedback diffusion. The image resultant of the diffusion is fed back to the simple cell layer. Furthermore, the boundary representation is also fed back to the boundary segmentation stage. In this way, the boundaries are adapted to the variations produced by the feedback diffusion, achieving a gradual boundary thinning. We also propose a modificated diffusive filling-in equation for obtaining better results in homogeneous regions. The behavior of the Grossberg-Todorovics equation reduces the homogenizing of the regions contained inside the boundaries. In order to solve this problem we introduce a new parameter, rho, called recovery parameter. This parameter regulates the activity variation margin of a node with respect to its initial value. With regard to the improvement in homogenizing, with a value for parameter rho near to zero, the resulting regions present a plain surface, making easy the chromosome bands separation.