Stereopsis, vertical disparity and relief transformations
J Gårding, J Porrill, J E W Mayhew, J P Frisby
Vision Research, vol. 35, no. 5, pp. 703-722, 1995.
The pattern of retinal binocular disparities acquired by a fixating
visual system depends on both the depth structure of the scene and the viewing
This paper treats the problem of interpreting the disparity pattern
in terms of scene structure
without relying on estimates of fixation position from eye movement control
and proprioception mechanisms.
We propose a sequential decomposition of this interpretation process into
disparity correctinadaEM>, whiCVAP/ch is used to compute
three-dimensional structure up to a relief transformation, and
disparity normalization, which is used to resolve the relief
ambiguity to obtain metric structure.
We point out that the disparity normalization stage can often be omitted,
since relief transformations preserve important properties such as
depth ordering and coplanarity.
Based on this framework we analyze three
previously proposed computational models of disparity processing;
the MLH model (Mayhew and Longuet-Higgins 1982),
the deformation model (Koenderink and van Doorn 1976)
and the polar angle disparity model (Weinshall
We show how these models are related, and argue that none of them
can account satisfactorily for available psychophysical data.
We therefore propose an alternative model, regional disparity
Using this model we derive predictions for a number of experiments
based on vertical disparity manipulations, and compare them to
available experimental data.
The paper is concluded with a summary and a discussion of the possible
architectures and mechanisms underlying stereopsis in the
human visual system.