221 research outputs found
Image-based texture styling for motion effect rendering
No full textA motion platform provides the vestibular stimuli that elicit the sensations of self-motion and thereby improves the immersiveness. A representative example is a 4D Ride, which presents a video of POV shots and motion effects synchronized with the camera motion in the video. Previous research efforts resulted in a few automatic motion effect synthesis algorithms for POV shots. Although effective in generating gross motion effects, they do not consider fine features on the ground, such as a rough or bumpy road. In this paper, we propose an algorithm for styling the gross motion effects using a texture image. Our algorithm transforms a texture image into a high-frequency style motion and merges it with the original motion while respecting both perceptual and device constraints. A user study demonstrated that texture styling could increase immersiveness, realism, and harmony.1
Camera space synthesis of motion effects emphasizing a moving object in 4D films
No full textFour-dimensional (4D) films, which provide special physical effects to the audience with audiovisual stimuli, are gaining more popularity and acceptance. One of the most frequent 4D effects is the object-based motion effect, which refers to the vestibular stimulus generated by a motion chair to emphasize a moving object of interest, e.g., the flying iron man, displayed on the screen. In this paper, we present an algorithm for synthesizing convincing object-based motion effects automatically from a given object motion trajectory. While previous approaches use the 2D object position on the screen as input, our method takes the 3D position and orientation of the object in the camera space and computes its motion proxy that reflects both the object translation and rotation, as well as its size to the viewers' eyes. The proxy is determined based on the results of a perceptual experiment that presents an optimal additive rule of the translation and rotation information scaled by the object's visual size. The motion proxy is fed to a motion cueing algorithm (MCA) that computes the command using a washout filter or model predictive control. The most appropriate MCA for our purpose is selected from six candidates by a user study. We also consider the effects of visual perception by incorporating two types of motion field equations into the computation of the visually perceived velocity. The results of a user study indicate that our algorithm can generate compelling object-based motion effects that better enhance the 4D film viewing experience than the previous methods.1
Octave-Spanning Supercontinuum Generation in Thermally Deposited As2S3 Waveguide on Wet-etched SiO2 Structure
No full textWe report octave -spanning supercontinuum generation in etch -less As2S3 film waveguide platform. The spectrum is extended from 1.05 to 2.71 p.m pumped by 45 pJ pulse energy at 1.56 p.m telecommunication wavelength. (.0 2019 The Author(s
Improving viewing experiences of first-person shooter gameplays with automatically-generated motion effects
No full textIn recent times, millions of people enjoy watching video gameplays at an eSports stadium or home. We seek a method that improves gameplay spectator or viewer experiences by presenting multisensory stimuli. Using a motion chair, we provide the motion efects automatically generated from the audiovisual stream to the viewers watching a frst-person shooter (FPS) gameplay. The motion efects express the game character's movement and gunfre action. We describe algorithms for the computation of such motion efects developed using computer vision techniques and deep learning. By a user study, we demonstrate that our method of providing motion efects signifcantly improves the viewing experiences of FPS game-play. The contributions of this paper are with the motion synthesis algorithms integrated for FPS games and the empirical evidence for the benefts of experiencing multisensory gameplays.1
Motion Effects: Perceptual Space and Synthesis for Specific Perceptual Properties
No full textIEEEA motion effect, the vestibular stimulus generated by a moving chair, is crucial in improving user experiences in many virtual reality (VR) and entertainment applications. However, the perceptual characteristics of motion effects remain unexplored to a great extent. This paper constructs a perceptual space that accounts for many motion effects based on their perceptual distances and then demonstrates smooth–rough and irregular–regular as its two primary perceptual dimensions. An authoring space is constructed with these two pairs as the axes. We also present methods for synthesizing new motion effects with a specific property in the authoring space. The contributions of this work are with new insights into the perceptual characteristics of motion effects and the first design methods of motion effects achieving desired perceptual properties.11Nsciescopu
High-Performance and Compact Silicon Photonic 3-dB Adiabatic Coupler Based on Shortest Mode Transformer Method
No full textA 2 × 2 3-dB coupler is one of the essential photonic components, as a building block of Mach-Zehnder interferometers, to realize large-scale photonic integrated circuits. Unlike typical 2 × 2 3-dB couplers based on direction couplers or multimode interference couplers, adiabatic couplers offer various advantages such as broadband operation and superior fabrication tolerance thanks to their unique operating mechanism of adiabatic mode evolution. However, an adiabatic coupler typically requires a long device length for ideal adiabatic operation without the excitations of unwanted modes. Here, we report on a compact 2 × 2 3-dB adiabatic coupler designed using the shortest mode transformer method. By optimizing the profile of the waveguide widths and the gap spacing, the compact 3-dB coupler was designed with a short coupling length of 23.2 μm. The fabricated device exhibits a 3-dB splitting ratio with less than ± 0.3 dB power oscillation and a low excess loss of 0.23 dB over a broad wavelength range of 1485–1620 nm. To the best of our knowledge, our coupler has the shortest length among the adiabatic couplers with a minimum feature size of 200 nm, reported to date
Silicon Photonic MEMS Phase-Shifter
No full textWe present a design for an analog phase shifter based on Silicon Photonic MEMS technology. The operation principle is based on a two-step parallel plate electrostatic actuation mechanism to bring a vertically movable suspended tapered waveguide in a first step into proximity of the bus waveguide and to tune the phase of the propagating coupled mode in a second step by actuation of the suspended waveguide to tune the vertical gap. In the coupled state, the effective index of the optical supermode and the total accumulated phase delay can be varied by changing the vertical separation between the adiabatically tapered suspended and the fixed bus waveguides. Simulations predict that pi phase shift can be achieved with an actuation voltage of 19 V, corresponding to a displacement of 19 nm. With an adiabatic coupler geometry, the optical signal can be coupled between the moving waveguide and the bus waveguide with low loss in a wide wavelength range from 1.5 mu m to 1.6 mu m keeping the average insertion loss below 0.3 dB. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
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