Depth Cues What is a cue –Independent source of information about depth (when interpreted) –Cue types Monocular static Monocular dynamic Binocular Metric, relative, ordinal
Possible Cue List Accomodation/ Convergence Arial perspective Stereopsis Height in visual field Motion disparity Occlusion Relative Size Relative density Linear Perspective Shading/shadows Texture gradients Kinetic depth (depth from motion) Dynamic occlusion (accretion deletion) Gravity
Range of Cue Effectiveness
Cue strength
Occlusion
Relative Size
Eye Height h
Atmospheric Perspective
Motion Parallax
Convergence Known angle, inter-ocular separation, Known angle => Depth of fixation point
Accommodation/Blur 1)Knowing your current focal length 2)Blur gradient
Stereo Disparity
Texture Gradient Size, Shape (compression), Density Knill, 1998
Perspective
Shadows/Interreflections
Shadows
Gravity Acceleration profile => Size + Depth Can affect scale of whole layout
Cue Combination Weighted combination (weak fusion) of estimates Cooperative combination –Disambiguation (cue promotion) –No indendepent estimates are possible Suppression (Veto)
What’s wrong? Ron Davis Six-Ninths Blue, 1966 Ames Room
Quant. Immersion Why did we read this? 1)controlled evaluation of performance in VR 2) Illustrates problems in purely empirical approach to quantifying cue effects in VR. 3) Cue du jour: Head movements
Problems Shows difficulties in direct empirical approach. –Can’t test everything –Prediction? What prediction? Quant. Immersion? Hey, wait a minute. Did they ever measure immersion?
Horopter