Radiometric Compensation of Nonlinear Projector Camera Systems by Modeling Human Visual Systems

Radiometric compensation is the process of adjusting the luminance and colour output of images on a display to compensate for non-uniformity of the display. In the case of projector-camera systems, this non-uniformity can be a product of both the light source and of the projection surface. Conventional radiometric compensation techniques have been demonstrated to compensate the output of a projector to appear correct to a camera, but a camera does not possess the colour sensitivity and response of a human. By correctly modelling the interaction between a projector stimulus and camera and human colour responses, radiometric compensation can be performed for a human tristimulus colour model rather than that of the camera. The result is a colour gamut which is seen to be correct for a human viewer but not necessarily the camera. A novel radiometric compensation method for projector-camera systems and textured surfaces is introduced based on the human visual system (HVS) colour response. The proposed method for modelling human colour response can extend established compensation methods to produce colours which are human-perceived to be correct (egocentric modelling). As a result, this method performs radiometric compensation which is not only consistent and precise, but also produces images which are visually accurate to an external colour reference. Additionally, conventional radiometric compensation relies on a solution of a linear system for the colour response of each pixel in an image, but this is insufficient for modelling systems containing a nonlinear projector or camera. In the proposed method, nonlinear projector output or camera response has been modelled in a separable fashion to allow for the linear system solution for the human visual space to be applied to nonlinear projector-camera systems. The performance of the system is evaluated by comparison with conventional solutions in terms of computational speed, memory requirements, and accuracy of the colour compensation. Studies include the qualitative and quantitative assessment of the proposed compensation method on a variety of adverse surfaces, with varying colour and specularity which demonstrate the colour accuracy of the proposed method. By using a spectroradiometer outside of the calibration loop, this method is shown to produce generally the lowest average radiometric compensation error when compared to compensation performed using only the response of a camera, demonstrated through quantitative analysis of compensated colours, and supported by qualitative results

How giving help to others can help young people deal with their own addiction.

ddiction is a significant problem among adolescents – it reduces academic performance, increases the likelihood of injury or criminal behavior, and has been estimated to cost US society as much as $500 billion every year. In new research, which builds on the idea that social connection and helping others can have benefits, Byron R. Johnson, Maria E. Pagano, Matthew T. Lee, and Stephen G. Post studied the effects of social isolation on young people who were being treated for alcohol and drug addiction. They find that socially estranged juveniles were more likely to relapse into addiction post-treatment, but also that those who gave help to others as part of the program were less likely to relapse and to commit crimes

Velir Web Tracking System

This project consisted of the design and development of a business reporting software to be used by Velir Studios. The software tool allows the employees at Velir Studios to quickly and effectively obtainimportant business information such as employee time cards, project budgets and resource allocation, invoice reporting and project burn-rate trends. By implementing this piece of software, Velir employees will be able to quickly export the data they wish to access into an excel document without having to manually enter each piece of information separately. The addition of the reporting software into the Velir management department will not only expedite the overall reporting process but will save them time and money in the future

Anatomic Fat Depots and Coronary Plaque Among Human Immunodeficiency Virus-Infected and Uninfected Men in the Multicenter AIDS Cohort Study.

Methods.  In a cross-sectional substudy of the Multicenter AIDS Cohort Study, noncontrast cardiac computed tomography (CT) scanning for coronary artery calcium (CAC) scoring was performed on all men, and, for men with normal renal function, coronary CT angiography (CTA) was performed. Associations between fat depots (visceral adipose tissue [VAT], abdominal subcutaneous adipose tissue [aSAT], and thigh subcutaneous adipose tissue [tSAT]) with coronary plaque presence and extent were assessed with logistic and linear regression adjusted for age, race, cardiovascular disease (CVD) risk factors, body mass index (BMI), and human immunodeficiency virus (HIV) parameters. Results.  Among HIV-infected men (n = 597) but not HIV-uninfected men (n = 343), having greater VAT was positively associated with noncalcified plaque presence (odds ratio [OR] = 1.04, P < .05), with a significant interaction (P < .05) by HIV serostatus. Human immunodeficiency virus-infected men had lower median aSAT and tSAT and greater median VAT among men with BMI <25 and 25-29.9 kg/m(2). Among HIV-infected men, VAT was positively associated with presence of coronary plaque on CTA after adjustment for CVD risk factors (OR = 1.04, P < .05), but not after additional adjustment for BMI. There was an inverse association between aSAT and extent of total plaque among HIV-infected men, but not among HIV-uninfected men. Lower tSAT was associated with greater CAC and total plaque score extent regardless of HIV serostatus. Conclusions.  The presence of greater amounts of VAT and lower SAT may contribute to increased risk for coronary artery disease among HIV-infected persons

Fast Radiometric Compensation for Nonlinear Projectors

Radiometric compensation can be accomplished on nonlinearprojector-camera systems through the use of pixelwise lookup ta-bles. Existing methods are both computationally and memory inten-sive. Such methods are impractical to be implemented for currenthigh-end projector technology. In this paper, a novel computation-ally efficient method for nonlinear radiometric compensation of pro-jectors is proposed. The compensation accuracy of the proposedmethod is assessed with the use of a spectroradiometer. Experi-mental results show both the effectiveness of the method and thereduction in compensation time compared to a recent state-of-the-art method

Constraints for Time-Multiplexed Structured Light with a Hand-held Camera

Multi-frame structured light in projector-camera systems affords high-density and non-contact methods of 3D surface reconstruction. However, they have strict setup constraints which can become expensive and time-consuming. Here, we investigate the conditions under which a projective homography can be used to compensate for small perturbations in pose caused by a hand-held camera. We synthesize data using a pinhole camera model and use it to determine the average 2D reprojection error per point correspondence. This error map is grouped into regions with specified upper-bounds to classify which regions produce sufficiently minimal error to be considered feasible for a structured-light projector-camera system with a hand-held camera. Empirical results demonstrate that a sub-pixel reprojection accuracy is achievable with a feasible geometric constraint

Inflammatory Markers Associated With Subclinical Coronary Artery Disease: The Multicenter AIDS Cohort Study.

BackgroundDespite evidence for higher risk of coronary artery disease among HIV+ individuals, the underlying mechanisms are not well understood. We investigated associations of inflammatory markers with subclinical coronary artery disease in 923 participants of the Multicenter AIDS Cohort Study (575 HIV+ and 348 HIV- men) who underwent noncontrast computed tomography scans for coronary artery calcification, the majority (n=692) also undergoing coronary computed tomography angiography.Methods and resultsOutcomes included presence and extent of coronary artery calcification, plus computed tomography angiography analysis of presence, composition, and extent of coronary plaques and severity of coronary stenosis. HIV+ men had significantly higher levels of interleukin-6 (IL-6), intercellular adhesion molecule-1, C-reactive protein, and soluble-tumor necrosis factor-α receptor (sTNFαR) I and II (all P<0.01) and a higher prevalence of noncalcified plaque (63% versus 54%, P=0.02) on computed tomography angiography. Among HIV+ men, for every SD increase in log-interleukin-6 and log intercellular adhesion molecule-1, there was a 30% and 60% increase, respectively, in the prevalence of coronary stenosis ≥50% (all P<0.05). Similarly, sTNFαR I and II in HIV+ participants were associated with an increase in prevalence of coronary stenosis ≥70% (P<0.05). Higher levels of interleukin-6, sTNFαR I, and sTNFαR II were also associated with greater coronary artery calcification score in HIV+ men (P<0.01).ConclusionsHigher inflammatory marker levels are associated with greater prevalence of coronary stenosis in HIV+ men. Our findings underscore the need for further study to elucidate the relationships of inflammatory pathways with coronary artery disease in HIV+ individuals

Positive Criminology and Rethinking the Response to Adolescent Addiction: Evidence on the Role of Social Support, Religiosity, and Service to Others

Adolescent addiction has emerged as a major public health problem. The greatest increase in alcohol and other drug use disorders can be found among youth. Concurrently, technological advances in policing coupled with aggressive prosecuting and sentencing practices have contributed to the growth of America’s correctional system. The assertive response of policing, courts, and corrections, however, have not prevented the dramatic rise of adolescent addiction. Unfortunately, there is no national data tracking addicted youth in the criminal justice system to evaluate what works when it comes to youth with addiction. This article reviews justice system responses to adolescent offenders with addiction, and promising approaches engaging juveniles in programmatic components of Alcoholics Anonymous (AA). This study highlights the role of spirituality, service to others, and social support in maintaining sobriety, reducing arrests, and lowering recidivism for adolescents court-referred to treatment. Recommendations for improving the response to adolescent offenders with addiction are offered