Search results for "ndc"
showing 10 items of 1025 documents
Multidimensional Integral Imaging and Recognition in Degraded Environments
2018
We present an overview of our work on multidimensional integral imaging systems. Integral-imaging-based multidimensional optical sensing and imaging will be described for 3-D visualization, seeing through obscurations, material inspection, augmented reality, biomedical applications, and object recognition from microscales to long-range imaging.
Optical implementation of micro-zoom arrays for parallel focusing in integral imaging.
2010
We report 3D integral imaging with an electronically tunable-focal-length lens for improved depth of field. The micro-zoom arrays are generated and implemented based on the concept of parallel apodization. To the best of our knowledge, this is the first report of parallel dynamic focusing in integral imaging based on the use of micro-zoom arrays.
Full-parallax 3D display from the hole-filtered depth information
2015
In this paper we introduce an efficient hole-filling algorithm for synthetic generation of microimages that are displayed on an integral imaging monitor. We apply the joint bilateral filter and the median filter to the captured depth map. We introduce in any step of the iterative algorithm with the data from a new Kinect capture. As a result, this algorithm can improve the quality of the depth maps and remove unmeasured depth holes effectively. This refined depth information enables to create a tidy integral image, which can be projected into an integral imaging monitor. In this way the monitor can display 3D images with continuous views, full parallax and abundant 3D reconstructed scene fo…
Toward 3D integral-imaging broadcast with increased viewing angle and parallax
2018
Abstract 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 microim…
Three-dimensional imaging system with both improved lateral resolution and depth of field considering non-uniform system parameters
2018
In this paper, we propose a new 3D passive image sensing and visualization technique to improve lateral resolution and depth of field (DoF) of integral imaging simultaneously. There is a resolution trade-off between lateral resolution and DoF in integral imaging. To overcome this issue, a large aperture and a small aperture can be used to record the elemental images to reduce the diffraction effect and extend the DoF, respectively. Therefore, in this paper, we utilize these two pickup concepts with a non-uniform camera array. To show the feasibility of our proposed method, we implement an optical experiment. For comparison in details, we calculate the peak signal-to-noise ratio (PSNR) as th…
Depth rendering of large incoherent scenes from integral images
2016
Integral imaging is a technique that provides the spatial and angular information of three-dimensional (3D) scenes through a single shot. Taking advantage of this capability, different applications have been developed. Some of these applications are the 3D display and digital post-processing, in particular depth-reconstruction from integral images.
Gaze cueing in naturalistic scenes under top-down modulation – Effects on gaze behaviour and memory performance
2022
Humans as social beings rely on information provided by conspecifics. One important signal in social communication is eye gaze. The current study (n = 93) sought to replicate and extend previous findings of attentional guidance by eye gaze in complex everyday scenes. In line with previous studies, longer, more and earlier fixations for objects cued by gaze compared to objects that were not cued were observed in free viewing conditions. To investigate how robust this prioritization is against top-down modulation, half of the participants received a memory task that required scanning the whole scene instead of exclusively focusing on cued objects. Interestingly, similar gaze cueing effects oc…
Improving Karhunen-Loeve based transform coding by using square isometries
2002
We propose, for an image compression system based on the Karhunen-Loeve transform implemented by neural networks, to take into consideration the 8 square isometries of an image block. The proper isometry applied puts the 8*8 square image block in a standard position, before applying the image block as input to the neural network architecture. The standard position is defined based on the variance of its four 4*4 sub-blocks (quadro partitioned) and brings the sub-block having the greatest variance in a specific corner and in another specific adjoining corner the sub-block having the second variance (if this is not possible the third is considered). The use of this "preprocessing" phase was e…
Gait Analysis Using Multiple Kinect Sensors
2014
A gait analysis technique to model user presences in an office scenario is presented in this chapter. In contrast with other approaches, we use unobtrusive sensors, i.e., an array of Kinect devices, to detect some features of interest. In particular, the position and the spatio-temporal evolution of some skeletal joints are used to define a set of gait features, which can be either static (e.g., person height) or dynamic (e.g., gait cycle duration). Data captured by multiple Kinects is merged to detect dynamic features in a longer walk sequence. The approach proposed here was been evaluated by using three classifiers (SVM, KNN, Naive Bayes) on different feature subsets.
Laser Triangulation 3D Point Cloud Sensor with Long Range and Large Field of View
2020
This paper presents a point cloud sensor design based on laser triangulation. Both the camera axis and the laser axis are rotating, making it possible to scan on short and long range in high resolution. A third axis moves the laser and camera into a new plane. The design is tested on a working prototype. To the authors knowledge a similar design has not been presented before.