title: Substituting depth for intensity and real-time phosphene rendering: visual navigation under low vision conditions.
abstract: Navigation and way finding including obstacle avoidance is difficult when visual perception is limited to low resolution, such as is currently available on a bionic eye. Depth visualisation may be a suitable alternative. Such an approach can be evaluated using simulated phosphenes with a wearable mobile virtual reality kit. In this paper, we present two novel approaches: (i) an implementation of depth visualisation; and, (ii) novel methods for rapid rendering of simulated phosphenes with an empirical comparison between them. Our new software-based method for simulated phosphene rendering shows large speed improvements, facilitating the display in real-time of a large number of phosphenes with size and brightness dependent on pixel intensity, and with customised output dynamic range. Further, we describe the protocol, navigation environment and system used for visual navigation experiments to evaluate the use of depth on low resolution simulations of a bionic eye perceptual experience. Results for these experiments show that a depth-based representation is effective for navigation, and shows significant advantages over intensity-based approaches when overhanging obstacles are present. The results of the experiments were reported in [1], [2].
authors.affiliation: NICTA Canberra Research Laboratory, Tower A, 7 London Circuit, Canberra ACT 2600, Locked Bag 8001, Canberra ACT 2601, Australia.
authors.forename: Paulette
authors.initials: P
authors.lastname: Lieby
authors.forename: Nick
authors.initials: N
authors.lastname: Barnes
authors.forename: Chris
authors.initials: C
authors.lastname: McCarthy
authors.forename: Nianjun
authors.initials: N
authors.lastname: Liu
authors.forename: Hugh
authors.initials: H
authors.lastname: Dennett
authors.forename: Janine G
authors.initials: JG
authors.lastname: Walker
authors.forename: Viorica
authors.initials: V
authors.lastname: Botea
authors.forename: Adele F
authors.initials: AF
authors.lastname: Scott
mesh_terms: D000465:Algorithms; D003867:Depth Perception / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009068:Movement / Q000502:physiology*; D016011:Normal Distribution; D010719:Phosphenes / Q000502:physiology*; D013997:Time Factors; D015354:Vision, Low / Q000503:physiopathology*; D055815:Young Adult