Showing papers in "The Journal of The Institute of Image Information and Television Engineers in 2004"
TL;DR: This stereoscopic display using a parallax polarizer barrier can solve the pseudoscopic image problem and enables multiple observers to view 3D images without the need for special glasses.
Abstract: A display system that does not require the use of special glasses is a useful technology in 3D imaging. Conventional lenticular and parallax barrier display systems have disadvantages such as pseudoscopic images. This report describes the development of a stereoscopic display using a parallax polarizer barrier to eliminate the pseudoscopic viewing area. This 3D display can solve the pseudoscopic image problem and enables multiple observers to view 3D images without the need for special glasses.
28 citations
TL;DR: A new eye-gaze input system with multi-indicators utilizing a personal computer and a home video camera to detect eye- gaze under natural light and compensates for measurement errors caused by head movement is proposed.
Abstract: Many systems to aid communication have been developed for seriously physically handicapped people such as ALS patients. The eye-gaze input system is currently being evaluated as a novel interface; it can be used to operate a computer with eye movement only. Most conventional eye-gaze input systems use of an infrared ray on the eyes to detect eye-gaze. However, prolonged irradiation could damage the eyes. This paper proposes a new eye-gaze input system with multi-indicators utilizing a personal computer and a home video camera to detect eye-gaze under natural light. It detects both vertical and horizontal eye-gaze through simple image analysis, and does not require special image processing units or sensors. It also compensates for measurement errors caused by head movement, i.e., it can detect eye-gaze with a high degree of accuracy. Therefore, it is capable distinguishing many indicators and its applications are expected to be expanded.
18 citations
TL;DR: The developed system should be a useful tool for standardizing MPRT as a quality analysis method and obtain a factor for converting from CCD camera pixel number to moving picture response time scale.
Abstract: We have developed a system for measuring moving picture response time (MPRT), which is designed to provide an index of image quality of moving pictures displayed on LCDs. the system uses a new analysis method to provide accurate and reliable MPRT values. the originality is in the way. We obtain a factor for converting from CCD camera pixel number to moving picture response time scale. The developed system should be a useful tool for standardizing MPRT as a quality analysis method.
15 citations
TL;DR: The proposed offset-block matching for ray-space interpolation combines pixel-based and block-based matching methods by limiting the search area and obtains better results than conventional matching methods.
Abstract: In this research, we address the problem of finding the best correspondence in matching algorithms in the edge area and we propose offset-block matching for ray-space interpolation. Conventional block matching methods are pixel-based, block-based and hierarchical methods. The pixel-based matching method performs well and satisfactorily detects correspondence in the edge area, when the search area is small. Block-based matching methods detect better than pixel-based methods where is a large disparity, however the detecting of correspondence in the edge area is not as accurate. The hierarchical block matching method performs relatively well in all areas. The proposed offset-block matching however combines pixel-based and block-based matching methods by limiting the search area and obtains better results than conventional matching methods. The proposed method has simultaneous advantage of both the pixel-based and the block-based matching methods. Furthermore, this method is suitable for distributed architecture of a video rendering system like FTV, when we need real-time interpolation.
15 citations
14 citations
TL;DR: An overview of D-vision and the technologies used for the rendering and projection hardware is given and the effectiveness of the system is shown by comparing it with conventional immersive projection displays.
Abstract: The multi-projection display system \"D-vision\" has a hybrid curved screen for immersive virtual environments. The screen consists of differently shaped surface elements that are partial surfaces of such objects as planes, spheres, cylinders and tori. High-quality stereoscopic images are generated with 24 PCs and 24 projectors. Our rendering algorithm using image processing hardware and 3-D graphics hardware realizes a seamless and non-distorted projection on the hybrid screen. Distortion of the images observed by two or more users is also reduced by the characteristic seamless shape of the screen. In this paper, we give an overview of D-vision and the technologies used for the rendering and projection hardware. We also show the effectiveness of our system by comparing it with conventional immersive projection displays. キーワ-ド:マ ルチ プロジェ クシ ョン,没 入型デ ィスプ レイ,バ ー チャル リア リテ ィ,レ ンダ リング,PCク ラスタ
12 citations
TL;DR: This paper proposes a modeling method from multiple viewpoints that uses an approximate shape, obtained by the volume intersection method with restrictive conditions set by the stereo matching method to generate a fine, dynamic, 3D object.
Abstract: We are researching a modeling algorithm for the moving human body to generate a fine, dynamic, 3D object. In this paper, we propose a modeling method from multiple viewpoints. This modeling method uses an approximate shape, obtained by the volume intersection method with restrictive conditions set by the stereo matching method.In addition, in order to map the image texture on the surface of the dynamic 3D objects, we propose a vertex texture mapping method based on ray-casting. Our modeling experiments were performed using 19 Firewire cameras. We were able to confirm that the proposed methods are effective for generating fine, dynamic, 3D objects. The dynamic 3D object generated can be displayed as an “animation” by using a VRML browser.
12 citations
TL;DR: The four-imager pickup method has contributed to the reduction of the camera's signal process circuitry and suppresses the false color caused by the non-linearity and the pixel-count difference between green and red (or blue).
Abstract: An experimental ultrahigh-definition color video camera system with 7, 680 (H) x 4, 320 (V) pixels has been developed using four 8-million-pixel CCDs. Each 8-million-pixel CCD with a progressive scanning rate of 60 frames per second has 4, 046 (H) x 2, 048 (V) effective imaging pixels, each of which is 8.4 micron2. We applied the four-imager pickup method to increase the camera's resolution. This involves attaching the CCDs to a special color-separation prism. Two CCDs are used for the green image, and the other two are used for the red and blue images. The spatial image sampling pattern of these CCDs relative to the optical image is equivalent to one with 32 million pixels in the Bayer pattern color filter. The prototype camera attains a limiting resolution of more than 2, 700 TV lines both horizontally and vertically, which is higher than that of an 8-million-pixel CCD. The sensitivity of the camera is 2, 000 lux, F 2.8 at approx. 50 dB of dark-noise level on the HDTV format. This camera system also has a new contour compensation circuit. It suppresses the false color caused by the non-linearity and the pixel-count difference between green and red (or blue). The technique has contributed to the reduction of the camera's signal process circuitry.
10 citations
TL;DR: A compact three-dimensional (3-D) display using a depth-fused 3-D (DFD) visual illusion in which two overlapped images with edges displayed at different depths can be perceived as a 3- D image is developed.
Abstract: We have developed a compact three-dimensional (3-D) display using a depth-fused 3-D (DFD) visual illusion in which two overlapped images with edges displayed at different depths can be perceived as a 3-D image. To make the display compact, we utilize the apparent luminance summation using the summation of polarization-angle changes at two transparent liquid-crystal displays instead of direct luminance summation. This enables moving color 3-D images to be shown on a compact display. Our compact DFD display is promising for various applications, such as cellular phones, personal digital assistants, and computer monitors.
10 citations
TL;DR: An anisotropic extension is presented to a bilateral filter which is an edge-preserving nonlinear filter to enhance stripe patterns such as fingerprints and nonphotorealistic rendering for generating flow patterns in pictures.
Abstract: An anisotropic extension is presented to a bilateral filter which is an edge-preserving nonlinear filter. Spatially anisotropic weights are adjusted on the basis of the gradient tensor of the luminance at each pixel of an image. This anisotropic bilateral filter is applied to enhance stripe patterns such as fingerprints and nonphotorealistic rendering for generating flow patterns in pictures. Extension of the low-pass characteristics to a band-pass ones strengthens the stripe enhancement effect of the filter. キーワー ド:非 等方バ イラテラルフィルタ,エ ッジ保存縞模様強調,ノ ンフォ トリア リステ ィック レンダ リング
10 citations
TL;DR: A novel method for arbitrary view synthesis that allows viewers to virtually fly through in real soccer scenes, and an application for fly-through soccer match observation is introduced.
Abstract: This paper presents a novel method for arbitrary view synthesis that allows viewers to virtually fly through in real soccer scenes. Multiple cameras situated around a stadium capture the action, and images shot from arbitrary viewpoints are generated by viewpoint interpolation, using projective geometry between neighboring cameras. The scenes are segmented according to their geometric properties.Dense correspondence matching between real views automatically occurs by applying projective geometry to each region. Superimposing the intermediate view images, synthesized in every region completes the virtual views of the entire soccer scene. Camera calibrations can be reduced, and correspondence matching requires no manual operation, allowing the proposed method to be applied to dynamic events in a large space. In addition to the view synthesis technique, we introduce an application for fly-through soccer match observation. This technology will lead to the creation of new media that can be applied to a variety of entertainment, from concerts to sporting events.
TL;DR: This study measured accommodation responses to a prototype 3D display which can display 64 directional images simultaneously and were very similar to those obtained for real objects.
Abstract: One of the problems of conventional 3D displays is the danger of using the ocular function. Observers feel fatigue because accommodation responses do not correspond to convergence. We have already proposed a new 3D display technique to solve this problem by displaying high-density directional images. This technique can be implemented by using modified 2D aligned telecentric optical systems. This technique enables several people to observe 3D images simultaneously without wearing 3D glasses and also offers color and moving 3D images. In this study we measured accommodation responses to a prototype 3D display which can display 64 directional images simultaneously. Measured accommodation responses to the prototype 3D display were very similar to those obtained for real objects.
TL;DR: A watermarking module that incorporates three MAPCAs (media accelerated processors for comsumer appliances) as art of a real-time embedding system for standard TV.
Abstract: We have developed two types of real-time video watermarking systems using a VLIW-based media processor. One is an embedding system for HDTV (High-Definition TV), and the other is an embedding system for standard TV. These systems preserve the picture quality of each video frame by using motion estimation and contour detection that optimizes the strength of the watermark. We have developed a watermarking module that incorporates three MAPCAs (media accelerated processors for comsumer appliances) as art of a real-time embedding system for standard TV. For HDTV, we have developed a watermarking system with seven watermarking modules. The system divides an HDTV video into seven segments so that the seven independent modules work in parallel.
[...]
TL;DR: The method of selectively sharpening images based on a coupled nonlinear diffusion process that was composed of a non linear diffusion term, a fidelity term, and an isotropic peaking term was extended to the removal of blurs in images due to image motion.
Abstract: We previously presented a method of selectively sharpening images based on a coupled nonlinear diffusion process that was composed of a nonlinear diffusion term, a fidelity term, and an isotropic peaking term. It could sharpen blurred edges without increasing noise visibility. This paper extends our method to the removal of blurs in images due to image motion. Motion blur is not only shift-variant but also anisotropic. To adapt our method to motion de-blurring, we replaced our isotropic peaking term, with an anisotropic peaking term steered in the direction of motion. We then derived discrete calculus to adapt it to the direction of motion. Through experiments with a test image containing artificial motion-blurs, we quantitatively evaluated sharpening. Our method with the anisotropic peaking term performed better than our prototypal method with the isotropic peaking term, and was robust against errors in the direction of motion.
TL;DR: NHK has developed a new program production management system called Beatus, designed to implement a more efficient and creative production environment and store video materials containing metadata, cut by cut and develop an integrated archival data-base.
Abstract: In order to use video materials efficiently and create a variety of programs, the characteristics, descriptions, suitability of materials metadata is as important as the materials themselves. The framework needed to manage this metadata is very important. NHK has developed a new program production management system called Beatus. This system covers all processes from planning, gathering, scripting, editing, broadcasting, to archiving. It is designed to; (1) implement a more efficient and creative production environment; (2) store video materials containing metadata, cut by cut; (3) utilize one item in a variety of ways and (4) develop an integrated archival data-base. Beatus has already been introduced to NHK's production field, and many programs are currently being produced using Beatus.
TL;DR: This paper descrive a non-distorted image projection method for an immersive projection display with a curved screen that contains a precise geometry and color correction for preprocessing with a digital camera, and a real-time geometry correction with real- time 3D rendering techniques.
Abstract: Various shaped screens have bee recently used for immersive projection displays. The ability to project a non-distorted image on a curved screen from arbitrary viewpoints is highly desirable. However, in previous techniques, the shape of the screen has been restricted, and we required geometrical information about screens and projectors. In this paper, we descrive a non-distorted image projection method for an immersive projection display with a curved screen. This method contains two approaches : the first is a precise geometry and color correction for preprocessing with a digital camera, and the second is a real-time geometry correction with real-time 3D rendering techniques. These methods need only geometrical information about the screen, and achieve a high quality image correction in real-time. We also used this method in the actual immersive projection display, and evaluated its effectiveness in some experiments.
TL;DR: This work used an iterative algorithm to estimate the intensity variation curve parameters and a weighting function to reduce the effect of noise contained in the highlight regions and to compute the separation of the two components.
Abstract: Separating the diffuse and specular components from the reflection of a 3D object surface is very important for generating highly realistic synthesized images in computer graphics applications. Most research on this separation has con- sidered only the case in which an object is illuminated by a single point light source. However, when an object is illuminated by one source, it can be difficult or impossible to acquire the r texture information of some visible regions on the object surface because of shading. To overcome this problem, we used two point light sources to illuminate the object to reduce the shaded regions. We used an iterative algorithm to estimate the intensity variation curve parameters and to compute the separation of the two components. To improve the separation quality, we used a weighting function to reduce the effect of noise contained in the highlight regions. Experiments using both synthesized and real data demonstrated that our method is effective and produces clear separation.
TL;DR: Experimental results show that image degradation using the proposed watermarking method is less than that with the conventional method when the number of embedded bits is the same.
Abstract: Watermarking has a trade-off relation between the number of embedded bits in a digital signature and image degradation. Therefore, we propose a watermarking method that improves the relationship between the number of embedded bits and image degradation. Experimental results show that image degradation using the proposed method is less than that with the conventional method when the number of embedded bits is the same.
TL;DR: The basic performance of a high S/N ratio CMOS image sensor with a real-time object-categorizing function and capabilities of converting all pixels from analog to digital, object separation, and video image capture is demonstrated.
Abstract: We demonstrate the basic performance of a high S/N ratio CMOS image sensor with a real-time object-categorizing function. The sensor has capabilities of converting all pixels from analog to digital, object separation, and video image capture. The image sensor is expected to be utilized in the communication and storage application fields offering high quality and large volume image data.
TL;DR: The HVC has unique properties for detecting objects, and ground region extraction was easy, and in the experiments, it was confirmed that detecting objects using the HVC was easy and effective.
Abstract: We described various properties of a Horizon View Camera (HVC), which is a unique optical system composed of a camera and a mirror. The HVC makes it possible to direct the optical axis of the camera to the horizon using the mirror. The upper part of the image was the reflected image in the mirror. This image included only objects on the ground a part from the ground itself. Another low part is the direct image in front of the HVC. These were obtained by the HVC at the same time. The HVC, therefore, has unique properties for detecting objects, and ground region extraction was easy. We described the HVC's structure and properties, and detected objects using these properties. In the experiments, we confirmed that detecting objects using the HVC was easy and effective.
TL;DR: The discussion includes psychophysical experiments conducted to evaluate the display performance, and the design, implementation, and evaluation are reported, and past and present problems are enumerated.
Abstract: TWISTER (Telexistence Wide-angle Immersive STEReoscope) is a panoramic autostereo display designed for face-to-face telecommunications. This device works as a cylindrical display by rotating multiple display units around an observer and by presenting time-varying patterns. Panoramic autostereo vision is achieved by using a “rotating parallax barrier” method, the effectiveness of which was already reported. To date, we have succeeded in presenting panoramic stereo motion pictures using the third prototype TWISTER III. Its design, implementation, and evaluation are reported, and past and present problems are enumerated. The discussion includes psychophysical experiments conducted to evaluate the display performance. Issues on constructing panoramic stereo images are also described.
TL;DR: The fringe printer for printing digitally synthetic holograms was improved to increase its stability and resolution and had mechanisms incorporated to detect surface undulations in the recording materials and control the beam waist only on the surface.
Abstract: Our fringe printer for printing digitally synthetic holograms, which we reported in a previous article, was improved to increase its stability and resolution. The old model was capable of printing elliptical dots in a diameter of 2×4 μm by focusing the beam of a laser diode onto a hologram dry plate. However, active control to focus the laser beam was not taken into account in the design, and therefore, the resolution and the stability were limited. The new fringe printer has had mechanisms incorporated to detect surface undulations in the recording materials and control the beam waist only on the surface. These improvements made it possible to reduce the dot size to 1.5×3 μm and to keep the dots size within a large area.
TL;DR: Strokes were generated using anisotropic smoothing filters (ASF) for generating pencil drawings and oil paintings from photographs using a non-photorealistic rendering (NPR) method.
Abstract: We present a non-photorealistic rendering (NPR) method for generating pencil drawings and oil paintings from photographs. Strokes were generated using anisotropic smoothing filters (ASF). These filters were preliminarily reviewed and extended to NPR methods. In an NPR method for pencil drawings, the original photograph was transformed into a stippled image, which was then filtered by ASFs. Orientation of strokes was aligned with a gradient in luminance or with that of depth values. Cross-hatching type drawings and colored pencil drawings were also presented. In an NPR for oil paintings, random noises were added to the original photograph, which was then filtered by the ASF. Spatial weights in the filter were extended to bandpass characteristics for enhancing strokes. Two types of oil paintings were given. The first one used the gradient of the original photograph and another one used the gradient of the photograph after noise addition.
TL;DR: This paper examines a virtual image observing process using LED as a reference beam and analyzes the color characteristics of the process, showing excellent color characteristics.
Abstract: Electro holography is a technique that can reconstruct moving color 3D images. Recently, several methods using a white light source or laser waves have been tested. However, since the reconstructing waves are applied closely approximated to the plane waves, the system tends to be very complicated and, hence, difficult to make smaller. In this paper, we examine a virtual image observing process using LED as a reference beam and analyze the color characteristics of the process. The results showed excellent color characteristics.
TL;DR: Using computer simulation, it is confirmed that ICI cancellers based on MMSE can reduce the bit error rate more than ICI cancellers based on zero-forcing under the Doppler-spread channel.
Abstract: In OFDM transmission, a loss of sub-carrier orthogonality due to Doppler-spread channels leads to inter-carrier interference (ICI). This problem is especially severe in mobile reception environments. ICI causes significant degradation in bit error rate characteristics and its influence increases as the carrier frequency or velocity of the receiver increases. We propose a method to reduce ICI caused by the Doppler-spread channel. The transmission channel is modelled by a combination of multiple Doppler-shifted propagation paths and their parameters, such as attenuation, relative delay, and Doppler-shift, and are then estimated using scattered pilot symbols. The ICI is cancelled by multiplying the inverse matrix of the estimated channel matrix by the received OFDM symbol vector. However, the ICI canceller emphasizes a noise component, so it does not improve the bit error rate characteristics sufficiently. In this paper, we propose an ICI canceller based on MMSE that does not emphasize a noise component. Using computer simulation, we confirmed that ICI cancellers based on MMSE can reduce the bit error rate more than ICI cancellers based on zero-forcing under the Doppler-spread channel.
TL;DR: Three distributed solutions are proposed based on a parent node and child node framework that allows independent encoding of each view of multi-view images.
Abstract: This paper discusses new methods for coding of multi-view images. Three distributed solutions are proposed based on a parent node and child node framework. A parent node encodes the whole image whereas a child node only partially. The proposed scheme allows independent encoding of each view. Experimental results show good performance of the proposed architectures at low bit-rates.
TL;DR: It was clarified that highly biased electrodes of the DTB-CCD absorbed most of the generation-recombination (g-r) currents at Si-SiO2 interfaces beneath their electrodes and also the currents between electrodes with low biases and electrodes with high biases.
Abstract: We propose a new interline CCD (IL-CCD) image sensor which combines buried photodiodes and CCD registers driven through a barrier (DTB-CCD). The performance of the image sensor was simulated by three-dimensional numerical analyses, emphasizing on dark current and charge capacity. It was clarified that highly biased electrodes of the DTB-CCD absorbed most of the generation-recombination (g-r) currents at Si-SiO2 interfaces beneath their electrodes and also the currents between electrodes with low biases and electrodes with high biases. The g-r currents were reduced by several orders at the interface under electodes with low biases, because holes were introduced under the interface. Most of the reduced g-r currents are also absorbed into their respective electrodes. However, a small part of the g-r currents generated at the above three interfaces flew into a channel, going over the potential barrier between the bottom of the SiO2 layer and channel, to become a dark current. When the barrier height was increased, dark currents were significantly reduced. Therefore, the IL-CCD image sensor enables a device with very few dark currents. When a 8.3μm(H)×12μm(V) pixel includes two photodiodes and four transfer electrodes was used, more than 4.5~5.0×104 electrons were transferred from photodiodes to CCD registers by 0V to 9.5V and -5.8 to 0V transfer pulses. Additionally, 4.0×104 electrons were transferred in the CCD by -5.8V to 0 V amplitude using conventional 4-phase driving pulses. キ ー ワー ド:イ メ ー ジ セ ン サ,イ ン タ ライ ンCCD,埋 込 み ホ トダ イ オ ー ド,CCD driven through barrier,暗 電 流,Charge capacity
TL;DR: The developed and demonstrated the effectiveness of a CLI canceller is demonstrated and the measured and analytical results of the coupling, fluctuation and delay spread of CLI are described.
Abstract: Coupling loop interference (CLI) between transmitting and receiving antennas must be suppressed to achieve broadcast wave relay in single frequency network (SFN) for digital terrestrial broadcasting. To avoid this interference, we have developed and demonstrated the effectiveness of a CLI canceller. An important step toward to achieving a relay station in SFN is to understand the propagation characteristics of CLI. This paper describes the measured and analytical results of the coupling, fluctuation and delay spread of CLI.