First Person Omnidirectional Video: System Design and Implications for

First Person Omnidirectional Video: System Design and Implications for Immersive Experience TVX 2015

Introduction Recording and sharing own experience completely has been an ultimate goal of media technology Omni-Directional Video (ODV) Capturing, displaying, interaction and control interface First person Omni-Directional Video (FODV) play important role in various applications E.g., entertainment, sports viewing, education and simulation training, news casting and therapy

Difficulties Design of capturing device for FODV wearable omnidirectional camera attached to the head no existing solution to satisfy all of robustness, wearability and eye-level position Quality of the first-person video from wearable cameras often shaky due to the body movement during capturing viewers often feel dizzy gets worse when the visual experience is immersive on a large screen or HMD Cybersickness

Contributions System design including capturing device and image processing for stabilizing FODV An investigation of cybersickness and user experience of the system Design implications for FODV from series of demo and workshop with their proposed FODV system

System Design JackIn Head system headgear with multiple cameras to capture omnidirectional video image processing for FODV stabilization the streaming video data and a playback system with screen or HMD

Headgear with Omnidirectional Camera Design considerations lower center of balance Captured environment should be close to the first person viewpoint Existing USB camera module has limitation in terms of image quality and video frame rate Each camera capture 960x1440 pixel, 100 fps

Image Stabilization for First Person ODV Calculates rotation then eliminate its rotation Re-produce smoothed rotation to follow the wears head direction with variable parameter Parameter depends on video context zero or quite small independent view (intense motion) larger value smoothed view (daily activities)

Evaluation of Cybersickness Scenarios Scenario (A): Walking in the town Scenario (B): Ball sports, watching to trace the ball Scenario (C): Ball sports, watching to trace another player

Experiment setup Participants perform six tasks in total (nonstabilization/stablization) A-N, A-S, B-N, B-S, C-N, C-S Each task is two minutes with a recovery time of 30 minutes interval Before and after each task, filled out a simulator sickness questionnaire (SSQ) the degree to which the participant felt nausea, oculomotor discomfort, disorientation, and general cybersickness 12 volunteers aged 20-38

Experiment Results The stabilization lessened the instances of cybersickness in each scenario There was a significant difference, between A-N and A-S, also between C-N and C-S

Analyses and Observations Active viewing behavior or not Without stabilization, strong disorientation when sudden motion in the direction opposite to their intention occurred (A, C) Stabilization would be a beneficial feature in FODV application Synchronization and asyncronization synchronization in motion of FODV and the spectator will lead lessen cybersickness, and also produce more realistic sensations (B)

Analyses and Observations (cont.) Existence of first person head direction is an important indication of awareness, and was eliminated by stabilization visualization of the wearer’s head direction in the immersive view can address this problem Cybersickness induced by translational movement even after stabilization the viewer expects to experience acceleration from the visual motion caused temporal cybersickness vertical translational motion, which cannot be eliminated by current stabilization process

Setup of Workshop 50 people HMD with head tracking and 15 inch laptop screen Activities Virtual travel: realistic feeling, revisit Virtual gymnastics: with vs. without gymnastics experience Virtual flying experience of the paraglider: virtual tutorial

Technical Challenges headgear should be less weighted and more suitable for wear, and even flexible form factor The stabilization should be improved in terms of compensating for the translational acceleration and vibration noise Realtime

Design Implications The risk of cybersickness even with footage of walking activities stabilization Overlaying ego-motion of the wearer in omnidirectional video will help the spectator to understand what the wearer was watching and doing

Design Implications (cont.) Synchronization of motion will lessen the induction of cybersickness, but also will produce an immersive realistic sensation adaptive control of stabilization will be one of possible application to increase immersion Viewing angle information of spectators The collected date of those information will generate meaningful information about social interest in ODV

Conclusion Omnidirectional video is one of promising media and have capability to capture an immersive first person experience Aimed to provide a solution for existing problems and to explore design implications Capturing device and image stabilization to alleviate cybersickness Evaluating and summarized the findings and insight into design implications Contribute a further exploration of first person omnidirectional video and expand the eco-system of interactive experience of various media