Video-rate computational super-resolution and integral imaging at longwave-infrared wavelengths

We report the first computational super-resolved, multi-camera integral imaging at long-wave infrared (LWIR) wavelengths. A synchronized array of FLIR Lepton cameras was assembled, and computational super-resolution and integral-imaging reconstruction employed to generate video with light-field imaging capabilities, such as 3D imaging and recognition of partially obscured objects, while also providing a four-fold increase in effective pixel count. This approach to high-resolution imaging enables a fundamental reduction in the track length and volume of an imaging system, while also enabling use of low-cost lens materials.Comment: Supplementary multimedia material in http://dx.doi.org/10.6084/m9.figshare.530302

Light field super resolution through controlled micro-shifts of light field sensor

Light field cameras enable new capabilities, such as post-capture refocusing and aperture control, through capturing directional and spatial distribution of light rays in space. Micro-lens array based light field camera design is often preferred due to its light transmission efficiency, cost-effectiveness and compactness. One drawback of the micro-lens array based light field cameras is low spatial resolution due to the fact that a single sensor is shared to capture both spatial and angular information. To address the low spatial resolution issue, we present a light field imaging approach, where multiple light fields are captured and fused to improve the spatial resolution. For each capture, the light field sensor is shifted by a pre-determined fraction of a micro-lens size using an XY translation stage for optimal performance

Micro Fourier Transform Profilometry (μ\muFTP): 3D shape measurement at 10,000 frames per second

Recent advances in imaging sensors and digital light projection technology have facilitated a rapid progress in 3D optical sensing, enabling 3D surfaces of complex-shaped objects to be captured with improved resolution and accuracy. However, due to the large number of projection patterns required for phase recovery and disambiguation, the maximum fame rates of current 3D shape measurement techniques are still limited to the range of hundreds of frames per second (fps). Here, we demonstrate a new 3D dynamic imaging technique, Micro Fourier Transform Profilometry ($\mu$FTP), which can capture 3D surfaces of transient events at up to 10,000 fps based on our newly developed high-speed fringe projection system. Compared with existing techniques, $\mu$FTP has the prominent advantage of recovering an accurate, unambiguous, and dense 3D point cloud with only two projected patterns. Furthermore, the phase information is encoded within a single high-frequency fringe image, thereby allowing motion-artifact-free reconstruction of transient events with temporal resolution of 50 microseconds. To show $\mu$FTP's broad utility, we use it to reconstruct 3D videos of 4 transient scenes: vibrating cantilevers, rotating fan blades, bullet fired from a toy gun, and balloon's explosion triggered by a flying dart, which were previously difficult or even unable to be captured with conventional approaches.Comment: This manuscript was originally submitted on 30th January 1

Toward 3D integral-imaging broadcast with increased viewing angle and parallax

We propose a new method for improving the observer experience when using an integral monitor. Our method permits to increase the viewing angle of the integral monitor, and also the maximum parallax that can be displayed. Additionally, it is possible to decide which parts of the 3D scene are displayed in front or behind the monitor. Our method is based, first, in the direct capture, with significant excess of parallax, of elemental images of 3D real scenes. From them, a collection of microimages adapted to the observer lateral and depth position is calculated. Finally, an eye-tracking system permits to determine the 3D observer position, and therefore to display the adequate microimages set. Summarizing, it is reported here, for the first time we believe, the application of eye-tracking technology to the display of integral images of 3D real scenes with bright background. Although we are reporting here only a proof-of-concept experiment, this result could have direct application in a close future for the broadcasting of 3D videos recorded in professional studio, for videoconferences or for on-line professional meetings

Post-production of holoscopic 3D image

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University LondonHoloscopic 3D imaging also known as “Integral imaging” was first proposed by Lippmann in 1908. It facilitates a promising technique for creating full colour spatial image that exists in space. It promotes a single lens aperture for recording spatial images of a real scene, thus it offers omnidirectional motion parallax and true 3D depth, which is the fundamental feature for digital refocusing. While stereoscopic and multiview 3D imaging systems simulate human eye technique, holoscopic 3D imaging system mimics fly’s eye technique, in which viewpoints are orthographic projection. This system enables true 3D representation of a real scene in space, thus it offers richer spatial cues compared to stereoscopic 3D and multiview 3D systems. Focus has been the greatest challenge since the beginning of photography. It is becoming even more critical in film production where focus pullers are finding it difficult to get the right focus with camera resolution becoming increasingly higher. Holoscopic 3D imaging enables the user to carry out re/focusing in post-production. There have been three main types of digital refocusing methods namely Shift and Integration, full resolution, and full resolution with blind. However, these methods suffer from artifacts and unsatisfactory resolution in the final resulting image. For instance the artifacts are in the form of blocky and blurry pictures, due to unmatched boundaries. An upsampling method is proposed that improves the resolution of the resulting image of shift and integration approach. Sub-pixel adjustment of elemental images including “upsampling technique” with smart filters are proposed to reduce the artifacts, introduced by full resolution with blind method as well as to improve both image quality and resolution of the final rendered image. A novel 3D object extraction method is proposed that takes advantage of disparity, which is also applied to generate stereoscopic 3D images from holoscopic 3D image. Cross correlation matching algorithm is used to obtain the disparity map from the disparity information and the desirable object is then extracted. In addition, 3D image conversion algorithm is proposed for the generation of stereoscopic and multiview 3D images from both unidirectional and omnidirectional holoscopic 3D images, which facilitates 3D content reformation

Symbiots: Conceptual interventions into energy systems

Symbiots set out to examine values such as ease-of-use, comfort, and rationality assumed within conventions of ‘good design’, in order to expose issues related to energy consumption and current human- (versus eco-) centered design paradigms. Exploring re-interpretations of graphical patterns, architectural configurations and electrical infrastructure typical in Swedish cities, Symbiots takes the form of a photo series in the genre of contemporary hyper-real art photography. Painting a vivid picture of alternatives to current local priorities around energy consumption, the three design concepts depicted are strangely familiar, alternatively humorous and sinister

Roadmap on 3D integral imaging: Sensing, processing, and display

This Roadmap article on three-dimensional integral imaging provides an overview of some of the research activities in the field of integral imaging. The article discusses various aspects of the field including sensing of 3D scenes, processing of captured information, and 3D display and visualization of information. The paper consists of a series of 15 sections from the experts presenting various aspects of the field on sensing, processing, displays, augmented reality, microscopy, object recognition, and other applications. Each section represents the vision of its author to describe the progress, potential, vision, and challenging issues in this field