Tali Treibitz (Electrical Engineering, Technion)
Wednesday, 11.11.2009, 11:30
Images taken through a medium may suffer from poor visibility and loss of
contrast. Light passing through undergoes absorption and scattering.
Wavelength dependent attenuation causes changes in color and brightness. In
addition, light that is scattered back from the medium into the camera
(backscatter) veils the object, degrading visibility and contrast. Low
signal to noise ratio imposes resolution limits, even if there is no blur.
Moreover, refraction between the medium and the camera (in air) causes
geometric distortions that harm geometric reconstruction. Nevertheless,
there is a strong need to perform vision tasks in such media. Thus, in this
work, we look both at photometric and geometrical aspects of imaging in
In the talk I give an overview of our contributions in this subject:
- Resolution limits imposed by noise
- Geometry limits: The non-single viewpoint nature of imaging systems
looking into water through a flat glass.
- Polarization-based removal of backscatter.
All the above is demonstrated in field experiments underwater and in haze.
* A PhD research under the supervision of Prof. Yoav Y. Schechner