The FERET database and evaluation procedure for face-recognition algorithms

Three-dimensional (3D) displays have become important for many applications including vision research, operation of remote devices, medical imaging, surgical training, scientific visualization, virtual prototyping, and more. In many of these applications, it is important for the graphic image to create a faithful impression of the 3D structure of the portrayed object or scene. Unfortunately, 3D displays often yield distortions in perceived 3D structure compared with the percepts of the real scenes the displays depict. A likely cause of such distortions is the fact that computer displays present images on one surface. Thus, focus cues-accommodation and blur in the retinal image-specify the depth of the display rather than the depths in the depicted scene. Additionally, the uncoupling of vergence and accommodation required by 3D displays frequently reduces one's ability to fuse the binocular stimulus and causes discomfort and fatigue for the viewer. We have developed a novel 3D display that presents focus cues that are correct or nearly correct for the depicted scene. We used this display to evaluate the influence of focus cues on perceptual distortions, fusion failures, and fatigue. We show that when focus cues are correct or nearly correct, (1) the time required to identify a stereoscopic stimulus is reduced, (2) stereoacuity in a time-limited task is increased, (3) distortions in perceived depth are reduced, and (4) viewer fatigue and discomfort are reduced. We discuss the implications of this work for vision research and the design and use of displays.

Vergence-accommodation conflicts hinder visual performance and cause visual fatigue.

Three central problems in the recent literature on visual attention are reviewed. The first concerns the control of attention by top-down (or goal-directed) and bottom-up (or stimulus-driven) processes. The second concerns the representational basis for visual selection, including how much attention can be said to be location- or object-based. Finally, we consider the time course of attention as it is directed to one stimulus after another.

VISUAL ATTENTION: Control, Representation, and Time Course

A wavelet-based image fusion tutorial

Immersion is the subjective impression that one is participating in a comprehensive, realistic experience. Interactive media now enable various degrees of digital immersion. The more a virtual immersive experience is based on design strategies that combine actional, symbolic, and sensory factors, the greater the participant's suspension of disbelief that she or he is "inside" a digitally enhanced setting. Studies have shown that immersion in a digital environment can enhance education in at least three ways: by allowing multiple perspectives, situated learning, and transfer. Further studies are needed on the capabilities of immersive media for learning, on the instructional designs best suited to each type of immersive medium, and on the learning strengths and preferences these media develop in users.

https://science.sciencemag.org/content/sci/323/5910/66.full.pdf

Immersive interfaces for engagement and learning.

An image sensor comprised of an array of photo elements (pixels) includes a device for randomly addressing individual pixels and a device for selectively varying the number of pixels which can be read out on any one reading cycle. The random addressing of pixels enables the readout of pixels located in selected regions of interest. Limiting the readout of the images to areas of interest allows an increase in the frame rate of the images. Relatively large groups of pixels can be read out simultaneously and the resulting signals can be merged into superpixel signals to provide high speed data capture, albeit at relatively lower resolution, since there will be a reduced number of data samples in each image. This feature is useful to rapidly scan and analyze a scene being viewed in order to locate an area of interest. Once an area of interest is located, the number of pixels read out on each cycle may be reduced to provide a higher resolution, lower speed, readout of the area of interest.

Multiple resolution image sensor

/pdf/handbook-of-virtual-environments-5brgdjv4t8.pdf

Handbook of virtual environments

Identifying the Involvement of Multiple Carnivore Taxa with Archaeological Bone Assemblages

This paper presents initial results in a study comparing the effectiveness of visible and infra-red (IR) imagery for detecting and recognizing faces in areas where personnel identification is critical, (e.g. airports and secure buildings). We compare the effectiveness of visible versus IR imagery by running three face recognition algorithms on a database of images collected for this study. There are both IR and visible images for each person in the database collected using the same scenarios. We used three very different feature-extraction and decision-making algorithms for our study to insure that the comparisons would not depend on a particular processing technique. We also present recognition results when visible and infra-red decision metrics are fused. The recognition results show that both visible and IR imagery perform similarly across algorithms and that fusion of IR and visible imagery as a viable means of enhancing performance beyond that of either acting alone. We examine the relative importance of different regions of the face for recognition. We also discuss practical issues of implementation, along with plans for the next phase of the study, face detection in an uncontrolled environment. Preliminary face detection results are presented.

Comparison of visible and infra-red imagery for face recognition

Energy dispersive x-ray diffraction spectra are obtained from numerous volume elements within an object. A feature set such as a set of cepstrum coefficients is extracted from each spectrum and classified by a trained classifier such as a neural network to provide an indication of whether or not contraband such as explosives is present in the volume element. Indications for adjacent volume elements are evaluated in conjunction with one another, as by an erosion process, to suppress isolated indications and thereby suppress false alarms.

Joseph Wilder

Papers

Multiple resolution image sensor

Handbook of virtual environments

Identifying the Involvement of Multiple Carnivore Taxa with Archaeological Bone Assemblages

Comparison of visible and infra-red imagery for face recognition

Analysis methods for energy dispersive X-ray diffraction patterns