Department of Electrical and Computer Engineering,
Engineering Science Building,
The University of Texas at Austin,
Austin, TX 78712-1084 USA
bevans@ece.utexas.edu -
bovik@ece.utexas.edu
Lossy video compression methods often rely on modeling the
abilities and limitations of the intended receiver, the Human
Visual System (HVS), to achieve the highest possible compression
with as little effect on perceived quality as possible. Foveation,
which is non-uniform resolution perception of the visual stimulus
by the HVS due to the non-uniform density of photoreceptor cells
in the eye, has been demonstrated to be useful for reducing bit
rates beyond the abilities of uniform resolution video coders. In
this work, we present real-time foveation techniques for low bit
rate video coding. First, we develop an approximate model for
foveation. Then, we demonstrate that foveation, as described by
this model, can be incorporated into standard motion compensation
and Discrete Cosine Transform (DCT) based video coding techniques
for low bit rate video coding, such as the H.263 or MPEG-4 video
coding standards, without incurring prohibitive complexity
overhead. We demonstrate that foveation in the DCT domain can
actually result in computational speedups. The techniques
presented can be implemented using the baseline modes in the video
coding standards and do not require any modification to, or post
processing at, the decoder.