Three-dimensional displays suitable for human visual field characteristics

Today’s three-dimensional display systems provide new advantages to end-users; they are able to support an auto-stereoscopic, no-glasses, three-dimensional experience with significantly enhanced image quality over previous generation technology. There have been particularly rapid advances in personal auto-stereoscopic three-dimensional display for desktop users brought about because of the opportunity to combine micro-optics and LCD displays coinciding with the availability of low cost desktop image processing and three-dimensional computer graphics systems. In this chapter we concentrate our detailed technical discussion on personal three-dimensional displays designed for desktop use as these are particularly benefiting from new micro-optic elements. We emphasize the systems aspect of three-dimensional display design believing it is important to combine good optical design and engineering with the correct digital imaging technologies to obtain a high quality three-dimensional effect for end users. The general principles discussed will be applicable to the design of all types of stereoscopic three-dimensional display.

Characteristics of the human visual field are well known to be different in central (fovea) and peripheral areas. Existing computational models of visual saliency, however, do not take into account this biological evidence. The existing models compute visual saliency uniformly over the retina and, thus, have difficulty in accurately predicting the next gaze (fixation) point. This paper proposes to incorporate human visual field characteristics into visual saliency, and presents a computational model for producing such a saliency map. Our model integrates image features obtained by bottom-up computation in such a way that weights for the integration depend on the distance from the current gaze point where the weights are optimally learned using actual saccade data. The experimental results using a large number of fixation/saccade data with wide viewing angles demonstrate the advantage of our saliency map, showing that it can accurately predict the point where one looks next.

HVS theory plays important role in the application of digital image watermarking technique. When inserting watermarking, the visual masking feature of HVS could be fully used to design digital watermarking algorithm with good perceived performance. When extracting watermarking from the damaged image, human's visual feature could be combined to recover the damaged image so as to obtain better effect. This article combines with human visual feature to study digital watermarking technique, utilizes watermarking redundant technique to insert watermarking, extracts watermarking in line with the damage situation of watermarking, and combines with visual redundancy feature to achieve a image scrambling algorithm that is easy to recover and a recovery scheme for damaged scrambling image.

Spatial indexing technology is widely used in Geographic Information Systems (GIS) and spatial databases. As a data retrieval technology, spatial indexing is becoming increasingly important in the big-data age. The purpose of this study is to propose a unified indexing strategy for the mixed data of a future marine GIS. First, data organisation of the system is described. Second, the display condition of each type of data is introduced. These conditions are the basis for the construction of a unified indexing structure. Third, a unified indexing structure for mixed data is presented. The construction process and the search method of the indexing structure are described. Finally, we implement the indexing strategy in our system “Automotive Intelligent Chart Three-dimensional Electronic Chart Display and Information Systems” (AIC 3D ECDIS). Our strategy can provide fast and integrated data retrieval. The spatial indexing strategy we propose breaks through the limitation of data types in our system. It can also be applied in other GIS systems. With the advent of the big-data age, mixed data indexing will become more and more important.

Medical image enhancement is to process the image so that the result is more suitable than the original image for analysis and diagnosis. The information of image is acquired by the observer's eyes, so in the image processing, the human visual characteristics (HVC) as an important factor should be well thought of. In the paper, we study HVC from testing the distinguishability of gray scale and the sensitivity to the structure of image, analyze the physiological character and psychological characters of human vision, and summarize the laws of HVC. A new medical image enhancement method is presented based on HVC. It divides the image into the smooth areas and detail areas, and uses different processing methods for the areas according to HVC. Experiment results demonstrate that the method enhances the edge detail information, and improves the image quality, thereby increases the veracity of diagnoses, makes the treatment approach more exact.

This paper introduces a three-dimensional light field display system, which is composed of a high-speed projector, a directional scattering mirror, a circular stainless-steel bearing plate, a rotating shaft and a high-speed micro motor. The system reduces information redundancy and computational complexity by reconstructing the light intensity distribution of the observed object, thus generating a real three-dimensional suspended image. The experimental results show that the suspension three-dimensional image can be generated by properly adjusting the projection rate of the image and the rotation speed of the rotating mirror (i.e. the motor speed). The clarity and accuracy of a three-dimension display depending on the number of slices selected, meaning that the more slices can be projected per minute, the finer the three-dimension display. Finally, this study provides the basic parameter matching, which shows the feasibility of developing a real light field 3D display system with stable performance, strong portability, easy implementation, and low cost. In short, naked-eye 3D allows the observer to view objects from any angle and direction, without the need for any auxiliary tools (such as glasses, helmets, etc.).

This thesis describes the design, implementation and operation of the coefficient generator and cursor for a three-dimensional on-line laser display system called STEREOMATRIX.

II 三次元画像ディスプレイ方式および装置

We have previously proposed the thin natural three-dimensional (3D) display system based on the reconstruction of parallax rays. In order to display real 3D scene, applying image-based rendering technique, we have also proposed a camera system that captures light ray data needed for reconstructing 3D images by using parallax rays reconstruction method from multiple images captured from multiple viewpoints. However, to reconstruct a 3D image of a real 3D object, many multiple images are required, because 3D images with an image depth of 25 cm can be displayed by the prototype thin 3D display. In order to reduce the number of required images, we used an interpolation algorithm suitable for the thin 3D display. This paper describes a 3D camera system for the thin 3D display, and also describes the experimental results.

Development of a three-dimensional auditory display system : Wenzel, E.M., and Wightmanm, F.L., and Foster, S.H.SIGCHI Bull, 1988, 20.2, 52–57, 19 refs.

Surveillance video cameras capture large amounts of continuous video streams every day. To analyze or investigate any significant events, it is a laborious and boring job to identify these events from the huge video data if it is done manually. Existing approaches sometimes neglect key frames with significant visual contents and/or select some unimportant frames with low/no activity. To solve this problem, in this paper, a video summarization technique is proposed by combining three multimodal human visual sensitive features, such as foreground objects, motion information, and visual saliency. In a video stream, foreground objects are one of the most important pieces of a video as they contain more detailed information and play a major role in important events. Moreover, motion is another stimulus of a video that significantly attracts human visual attention. To obtain this, motion information is calculated in the spatial domain as well as the frequency domain. Spatial motion information can select object motion accurately; however, it is sensitive to illumination changes. On the other hand, frequency motion information is robust to illumination change, although it is easily affected by noise. Therefore, motion information in both the spatial and the frequency domains is employed. Furthermore, the visual attention cue is a sensitive feature to measure the indication of a user's attraction label for determining key frames. As these features individually cannot perform very well, they are combined to obtain better results. For this purpose, an adaptive linear weighted fusion scheme is proposed to combine the features to rank video frames for summarization. Experimental results reveal that the proposed method outperforms the state-of-the-art methods.

Product packaging design is a work that integrates graphic design and three-dimensional design. 3D visualization technology and digital virtual interaction technology in virtual reality are developing rapidly in packaging design applications. On the one hand, this study discusses the application of digital technology in the three-dimensional design of packaging structure, including packaging carton structure design, packaging container modeling design, and packaging two-dimensional visual design. On the other hand, this study studies the color correction algorithm of packaging design and proposes a color correction based on the visual characteristics of human eyes. The pattern search algorithm finds a local optimum, and the initial value affects the correction result. Therefore, inspired by the color perception properties of the human visual system, the image is corrected by combining visual multichannel and visual nonlinearity. The experimental results of the algorithm are more consistent with human visual perception.

An adaptive Fuzzy Inference Perceptual model has been proposed for watermarking of video streams. The model is designed to be adaptive to the human visual characteristics to attest the owner identification and discourage the unauthorized copying. The proposed model integrates the human visual characteristics of video motion sub-regions, in the frequency multi-resolution wavelet domain, with multi-dimensional fuzzy inference perceptual model. The designed fuzzy multi-variable input system inherits luminance, texture and gradient to generate an adaptive watermark embedding strength factor. Interacting motion estimation is applied for the selection of the candidate frames and sub-blocks. A fuzzy-based scheme has been proposed to generate a perceptual membership degree for strength watermark embedding factor for the selected candidate motion blocks. Experiments have been carried out with different benchmark test videos of different sizes, visual characteristics and sampling rates. Various sizes of watermark signatures have been applied on the model. Several experimental attacks have been applied such as frame dropping, frame averaging, JPEG compression, Gaussian noises. It manifests considerable robustness against various geometric and signal processing attacks. Several attacks have been applied to the proposed scheme and the experiments revealed promising results in terms of visual quality and extracted watermark distortion. In addition, the model has been compared with different other watermarking schemes in literature. The proposed model showed superior performance in terms of fidelity, robustness to attacks and high level of imperceptibility.

I investigate the optical transfer function of three-dimensional display systems. Moreover, I obtain an average sampled modulation transfer function describing discrete, sampled display systems and show that in the proper limit of geometrical optics it is equivalent to the shift-invariant optical transfer function. I apply the theory to describe holographic stereograms and discuss the effects of amplitude and phase filters on the optical resolution.

We propose a three-dimensional (3-D) holographic display system which consists of a phase-only spatial light modulator (SLM) and a modified 4-f system. The 3-D scene is generated from OpenGL, and the point source algorithm with anti-aliasing technique is used to generate the Fresnel hologram. A modified 4-f system is proposed to produce distortion-free magnification of the 3-D image and eliminate the zero-order interruption of the 3-D holographic imaging system. This method can make efficient utilization of the space-bandwidth product of the SLM, which promises the image quality and keeps the 3-D imaging zone unchanged. Numerical simulations and optical experiments are performed, and the results show that our proposed method can reconstruct enlarged 3-D optical image with correct magnification factor and low image noise.