Infrared face recognition: a comprehensive review of methodologies and databases

Automatic face recognition is an area with immense practical potential which includes a wide range of commercial and law enforcement applications. Hence it is unsurprising that it continues to be one of the most active research areas of computer vision. Even after over three decades of intense research, the state-of-the-art in face recognition continues to improve, benefitting from advances in a range of different research fields such as image processing, pattern recognition, computer graphics, and physiology. Systems based on visible spectrum images, the most researched face recognition modality, have reached a significant level of maturity with some practical success. However, they continue to face challenges in the presence of illumination, pose and expression changes, as well as facial disguises, all of which can significantly decrease recognition accuracy. Amongst various approaches which have been proposed in an attempt to overcome these limitations, the use of infrared (IR) imaging has emerged as a particularly promising research direction. This paper presents a comprehensive and timely review of the literature on this subject. Our key contributions are: (i) a summary of the inherent properties of infrared imaging which makes this modality promising in the context of face recognition, (ii) a systematic review of the most influential approaches, with a focus on emerging common trends as well as key differences between alternative methodologies, (iii) a description of the main databases of infrared facial images available to the researcher, and lastly (iv) a discussion of the most promising avenues for future research.Comment: Pattern Recognition, 2014. arXiv admin note: substantial text overlap with arXiv:1306.160

Biometric Systems

Biometric authentication has been widely used for access control and security systems over the past few years. The purpose of this book is to provide the readers with life cycle of different biometric authentication systems from their design and development to qualification and final application. The major systems discussed in this book include fingerprint identification, face recognition, iris segmentation and classification, signature verification and other miscellaneous systems which describe management policies of biometrics, reliability measures, pressure based typing and signature verification, bio-chemical systems and behavioral characteristics. In summary, this book provides the students and the researchers with different approaches to develop biometric authentication systems and at the same time includes state-of-the-art approaches in their design and development. The approaches have been thoroughly tested on standard databases and in real world applications

Development of Tissue Engineered Scaffolds for Cardiovascular Repair and Replacement in Pediatric Patients

Congenital Heart Diseases (CHD) are abnormalities present in the heart and great vessels at birth. It is one of the most frequently diagnosed congenital disorders, affecting approximately 40,000 live birth each year in the United States. The incidence of new CHD patients and the relative distribution of defects have not changed over time and remain a birth rate function. Out of the new patients found to have CHD each year, an estimated 2,500 patients have a defect that requires a substitute, non-native valve, or conduit artery to replace structures that are congenitally absent or hypoplastic. Materials in current use for conduit and valve replacement involve varying degrees of stiffness and flexibility, durability, calcification, susceptibility to infection, thrombosis, and a lack of growth potential for the replacement. Biomaterials developed using tissue engineering principles could overcome the limitations encountered with current strategies. This research aims to develop potentially superior valves and conduits using acellular xenograft tissues that are physically cross- linked to protect the Extracellular Matrix (ECM) from rapid degradation. The hypothesis is that such a replacement graft would allow cellular ingrowth of host cells and potentially enable regenerative growth and remodeling of the graft. A decellularization protocol was developed, and the most effective crosslinker protecting the extracellular matrix structure was identified. The decellularized scaffolds crosslinked with Penta galloyl glucose (PGG) were analyzed in-vitro for stability and mechanical properties, in subcutaneous rat and in valve replacement in sheep-models to determine the biocompatibility and functionality of the developed scaffolds. Tissue-engineered scaffolds prepared from decellularized PGG treated tissues were found to have mechanical properties comparable to that of native tissues, while being more resistant to enzymatic degradation. Subcutaneous implantation of scaffolds demonstrated their biocompatibility and superior resistance to calcification compared to currently available glutaraldehyde fixed tissues. The tissue-engineered conduits and valves implanted in large animal models also demonstrated adequate implant functionality, cellular infiltration, implant remodeling, and growth of the implants. PGG treated decellularized xenografts could be an effective replacement option for pediatric patients, reducing the need for reoperations required with current devices