Novel Depth Cues from Uncalibrated Near-field Lighting

1
Novel Depth Cues from Uncalibrated Near-field
Lighting Sanjeev J. Koppal and Srinivasa G.
Narasimhan
1. Plane-Scene Intersections
Light source moves in a line
Detect intensity maxima Results appear
similar to light-striping Intensity Maxima
in Lambertian Scenes
The intensity, E, at any time t for a lambertian
scene is given by
Scene
Input Images
Metal Office Desk Plane-Scene
Intersections
P
The location of the maxima is found by setting
the derivative to zero
Plane Perpendicular to source path.
Plane-Scene Intersections
The maxima location occurs at P if the light
source is close to scene and D is small.
Painted House Vertical and Horizontal
Intersections
2. Depth Ordering for Homogeneous Scenes
Light source moves in a plane
Integrate pixel intensities
Ordering as a pseudo depth
Overlapping Incident Angles
Scene
Input Images
Polyresin Statue Depth Ordering
Rendering
The integral of intensities at any scene point P,
consists of angles that either overlap with
those at scene point Q or are different
Right Plane
Left Plane
Depth Ordering
Image Plane
Evaluation using Renderings
3. Symmetry Pairs for Homogeneous Scenes
Light source moves in
Match identical intensities Method works
for isotropic BRDFs bisecting plane
Lambertian Torrance-Sparrow Scores
Oren-Nayar Scores
Depth Ordering
Correctly Ordered Fraction
Correctly Ordered Fraction
0.80
0.95
Scene
Input Images
0.75
0.65
0
1
Roughness
Roughness
0
1
Lambertian Torrance-Sparrow Scores
Oren-Nayar Scores
Plane-Scene Intersections
Plane Fit Error
Plane Fit Error
Metal Office Desk Symmetry Pairs
Symmetry Pairs
Roughness
Roughness