Techniques of Binarization, Thinning and Feature Extraction Applied to a Fingerprint System

Abstract

A large volume of images of fingerprints are collected and stored to be used in various systems such as in access control and identification records (ID). Systems for automatic fingerprint recognition perform searches and comparisons with a database. Biometric recognition is based on two fundamental premises: the first is that digital printing must have permanent details, and the second is the information unit. From these premises, a system analyzes the fingerprint image to extract the information and then compares the data in the verification mode or identification mode. , Extraction techniques must be used to obtain the fingerprint data. These techniques use binarization, thinning and features extraction algorithms which are computational methods that can be applied to digital image processing used in scientific research and security issues. This paper presents a comparative analysis of four thresholding techniques (Niblack, Bernsen, Fisher, Fuzzy), two thinning techniques (Stentiford and Holt) and a feature extraction (Cross Number) technique to evaluate the best performance of the algorithms in fingerprint images. To develop this project a set of 160 fingerprint images was used in experiments and analysis. The results point out the positive and negative points of the different algorithms. The system was developed in the C/C++ language.

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Autonomous Underwater Vehicle to Inspect Hydroelectric Dams

Driven by the rising demand for underwater operations in the fields of dam structure monitoring, ecosystems of reservoir lakes from Hydropower Plants (HPP) and mining and oil, underwater robotics is increasing rapidly. The increase in exploration, prospecting, monitoring and security in lakes, rivers and sea, both in commercial applications such as scientific applications, has led large companies and research centers to invest in the development of underwater vehicles. The purpose of this work is to develop and evaluate the performance of a dedicated expert system for an Autonomous Underwater Vehicle (AUV) to inspect hydroelectric dams, focusing efforts on mechatronic project based on dimensioning structural elements and machinery and elaborating the sensory part, which includes navigation sensors and sensors of environment conditions, as well as its vision system to detect and measure cracks on hydroelectric dams. The integration of sensors in an intelligent platform provides a satisfactory control of the vehicle, allowing the movement of the submarine on the three spatial axes. Because of the satisfactory fast response of the sensors, it is possible to determine the acceleration and inclination besides his attitude in relation to the trajectory instantaneously taken, and geometry and depth of the cracks. This vehicle will be able to monitor the physical integrity of dams, making acquisition and storage of environment parameter such as temperature, dissolved oxygen, pH and conductivity as well as document images of the biota from reservoir lakes HPP, with minimized cost, high availability and low dependence on a skilled workforce to operate it.

http://www.ijcaonline.org/archives/volume101/number11/17728-8801

An OCR System for Numerals Applied to Energy Meters

This work describes a prototype of an OCR (Optical Character Recognition) system designed for reading digits of power measurement devices, using Artificial Neural Networks. The motivation for this work is the implementation of an alternative automatic measurement system to be used in a prepaid power system - SEPPRA. Prototype software using Computer Vision techniques and pattern recognition through Neural Networks is implemented in the C++/Windows platform. Considering this application, adaptive threshold methods are compared in order to choose the more appropriated algorithm of binarization. Several algorithms are implemented and evaluated under different conditions of zoom and camera focus. The system works satisfactorily and can be carried to other platforms, making possible its production in commercial scale. 

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The Modeling of Mosaic Generation System Using Coloured Petri Nets

A typical mobile robot is constituted by subsystems such as: perception, localization, navigation and movement control. The perception system is responsible to acquire data from the space where the robot is placed. This data, after being stored, is processed to be used to generate information on the location where the robot is placed, through its location system. The mosaic might be defined as a set of photos with approximate scale, in one specific region, cut and assembled, artistically or technically in a way to give the impression that the set of pictures is a single image. From the need of a mosaic generation system, it was performed a construction of a coloured Petri net to enable the modeling of a mosaic generation system. This work offers the mosaic generation system modeling using coloured Petri nets. The model was tested on the software CPN Tools through an exhaustive and random transitions fire. 

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pSnakes: um novo modelo de contornos ativos radial

Abstract

Active contours are image segmentation methods that minimize the total energy of the contour to be segmented. Among the active contour methods, the radial methods have lower computational complexity and can be applied in real time. This work aims to present a new radial active contour technique, called pSnakes, using the 1D Hilbert transform as external energy. The pSnakes method is based on the fact that the beams in ultrasound equipment diverge from a single point of the probe, thus enabling the use of polar coordinates in the segmentation. The control points or nodes of the active contour are obtained in pairs and are called twin nodes. The internal energies as well as the external one, Hilbertian energy, are redefined. The results showed that pSnakes can be used in image segmentation of short-axis echocardiogram images and that they were effective in image segmentation of the left ventricle. The echo-cardiologist's golden standard showed that the pSnakes was the best method when compared with other methods. The main contributions of this work are the use of pSnakes and Hilbertian energy, as the external energy, in image segmentation. The Hilbertian energy is calculated by the 1D Hilbert transform. Compared with traditional methods, the pSnakes method is more suitable for ultrasound images because it is not affected by variations in image contrast, such as noise. The experimental results obtained by the left ventricle segmentation of echocardiographic images demonstrated the advantages of the proposed model. The results presented in this paper are justified due to an improved performance of the Hilbert energy in the presence of speckle noise.

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ARTIGO ELSEVIER

DESENVOLVIMENTO DO PROJETO DE AUTOMAÇÃO PREDIAL NO SHOPPING IANDÊ: ESTUDO DE CASO

A automação dos sistemas prediais nos edifícios denominados inteligentes se tornou essencial na atualidade, pois oferece vantagens como segurança, conforto e rendimento. O presente trabalho visa o desenvolvimento do projeto de automação predial dos sistemas de iluminação, esgoto, drenagem, irrigação recalque e monitoração de temperatura de loja inseridos no Shopping Iandê previsto em contrato inicial entre a empresa contratada para implantação da automação e o cliente (shopping). A fundamentação teórica baseia-se nos conceitos e nas características das tecnologias do controlador lógico programável, do sistema SCADA e do protocolo MODBUS para efetuar o controle, a supervisão e a integração desses sistemas. Através da metodologia de estudo de caso descreveu-se de forma concisa o princípio de funcionamento dos sistemas automatizados e o aplicativo de supervisão elaborado para o projeto. Os resultados são estabelecidos dos testes preliminares realizados em bancadas, os quais analisam a lógica de programação dos controladores coerente com o desejado o comportamento dos sistemas, a comunicação em tempo real (online) entre os CLP e o SCADA e as animações, aos comandos e aos set points enviados pelo aplicativo de supervisão. A realização desse trabalho proporciona conhecimentos sobre as tecnologias envolvidas em um projeto prático, tendo a credibilidade para ser utilizado em outros projetos com a mesma finalidade. 

Autora: Enga. JANINE GOMES DE HOLANDA OLIVEIRA

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