Phase singularities in scale-space
نویسندگان
چکیده
This paper concerns the use of phase information from band-pass signals for the measurement of binocular disparity, optic ow, and image orientation. Towards this end, one of the important properties of band-pass phase information is its stability with respect to small geometric deformations and contrast changes. However, in particular regions phase can also be very unstable due to the occurrence of phase singularities. We discuss the existence of phase singularities, and their relation to the neighbourhoods where phase is unreliable. Moreover, we present a simple method for detecting these regions of instability.
منابع مشابه
Geometry of phase and polarization singularities, illustrated by edge diffraction and the tides
In complex scalar fields, singularities of the phase (optical vortices, wavefront dislocations) are lines in space, or points in the plane, where the wave amplitude vanishes. Phase singularities are illustrated by zeros in edge diffraction and amphidromies in the heights of the tides. In complex vector waves, there are two sorts of polarization singularity. The polarization is purely circular o...
متن کاملبررسی شکافتگی کوچک و دیگر تکینگیهای آینده عالم و برقراری قانون دوم ترمودینامیک در نظریه
The future singularities are possible in a universe that is described by F(R) theory. In previous studies the occurrence of the singularities in F(R) theory have been considered by using a special function for the Hubble parameter and calculating the F(R) function for each of the singularities. Using the specified Hubble parameter causes some difficulties in the study of the second law of therm...
متن کاملScale - Space Behaviour and Invariance Properties of Di erential Singularities ?
This article describes how a certain way of expressing low-level feature detectors, in terms of singularities of di erential expressions de ned at multiple scales in scale-space, simpli es the analysis of the e ect of smoothing. It is shown how such features can be related across scales, and generally valid expressions for drift velocities are derived with examples concerning edges, junctions, ...
متن کاملSpontaneous symmetry breaking and finite-time singularities in d-dimensional incompressible flows with fractional dissipation
We investigate the formation of singularities in incompressible flows governed by Navier-Stokes equations in d 2 dimensions with a fractional Laplacian |∇|α. We derive analytically a sufficient but not necessary condition for the solutions to remain always smooth and show that finite-time singularities cannot form for α αc = 1+ d/2. Moreover, initial singularities become unstable for α>αc. The ...
متن کاملScale - Space Behaviour and Invariance
This article describes how a certain way of expressing low-level feature detectors, in terms of singularities of diierential expressions deened at multiple scales in scale-space, simpliies the analysis of the eeect of smoothing. It is shown how such features can be related across scales, and generally valid expressions for drift velocities are derived with examples concerning edges, junctions ,...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Image Vision Comput.
دوره 9 شماره
صفحات -
تاریخ انتشار 1991