Multispectral Imaging using a Stereo Camera: Concept, Design and Assessment

This is the copy of journal's version originally published in EURASIP Journal on Advances in Signal Processing 2011:57. Reprinted with permission of EURASIP: http://asp.eurasipjournals.com/This paper proposes a one-shot six-channel multispectral color image acquisition system using a stereo camera and a pair of optical filters. The two filters from the best pair selected from among readily available filters such that they modify the sensitivities of the two cameras in such a way that they produce optimal estimation of spectral reflectance and/or color are placed in front of the two lenses of the stereo camera. The two images acquired from the stereo camera are then registered for pixel-to-pixel correspondence. The spectral reflectance and/or color at each pixel on the scene are estimated from the corresponding camera outputs in the two images. Both simulations and experiments have shown that the proposed system performs well both spectrally and colorimetrically. Since it acquires the multispectral images in one shot, the proposed system can solve the limitations of slow and complex acquisition process and costliness of the state of the art multispectral imaging systems, leading to its possible uses in widespread applications

Different Points of a Continuum? Cross Sectional Comparison of the Current and Pre-contact Psychosocial Problems among the Different Categories of Adolescents in Institutional Care in Nigeria

<p>Abstract</p> <p>Background</p> <p>The combination of adverse social indicators and a predominantly youthful population puts Nigeria, and indeed many countries of sub-Sahara Africa, at the risk of explosion in the number of youth coming in contact with the juvenile justice system. Despite this risk, custodial childcare systems in the region are still poorly developed with both juvenile offenders and neglected adolescents coming in contact with the systems being kept in the same incarcerating facility. The needs of these different groups of adolescents may be different. Knowing their common and unique needs can inform common prevention strategies and ensure that specific service-needs of different categories of adolescents in institutional custody are met.</p> <p>Methods</p> <p>Data on the family background, pre-contact social circumstance, neurological and anthropometric profiles, and certain aspects of mental health of adolescents drawn from two juvenile justice institutions in Nigeria were obtained. The results for the adolescents on ‘criminal code’ and those admitted as a case of child neglect were compared using chi-square and odd ratios.</p> <p>Results</p> <p>Participants were 211 adolescents comprising of 158 on ‘criminal code’ and 53 declared as ‘neglected’. A lot of similarities were found. For instance, the prevalence of parental separation, family transition, experience of street-life and lifetime exposure to traumatic events and posttraumatic stress was equally high among the two groups of adolescents. The adolescents on ‘criminal code’ however had significantly higher prevalence of conduct and alcohol/substance use disorders while the child neglect group had poorer anthropometric profiles and higher prevalence of neurological disorders.</p> <p>Conclusions</p> <p>Child neglect and juvenile delinquency in Nigeria may truly be different points of a continuum. There are however fundamental differences that can warrant specific prevention strategies and tailor-made service provision while in custodial care.</p