25 research outputs found
SIP COMPRESSION
The wired line network has been well studied and widely used for a long
time. Most of its protocols are so successful that passed the test of
time. There are many
similar tasks in mobile and wired line environment, and we would like
to achieve compatible, inter-working solutions. So it is a plausible
idea to use the protocols of the wired line network in mobile
environment too. However, the mobile and wired line environment differ
significantly; mainly the bandwidth is different in the two networks.
Although the difference is going to be smaller with the help of new
generation of mobile networks, it will
still remain significant. An acceptable solution is to compress these
protocols. We have not found such a solution in the literature
so our opinion is that this article is the first dealing with SIP compression.
We have created a demonstration
system, which connects two SIP user agents to each
other and ensures the compression and decompression of the
messages between them.
In this article we show our development about adapting various compressing
algorithms for SIP compression, and we evaluate them
A Fully Three-Dimensional Method for Facial Reconstruction Based on Deformable Models
International audienceTwo facial models corresponding to two deceased subjects have been manually created and the two corresponding skulls have been dissected and skeletonized. These pairs of skull/ facial data have been scanned with a CT scanner, and the computed geometric three-dimensional models of both skulls and facial tissue have been built. One set of skull/facial data will be used as a reference set whereas the second set is used as ground truth for validating our method. After a semi-automatic face-skull registration, we apply an original computing global parametric transformation T that turns the reference skull into the skull to be reconstructed. This algorithm is based upon salient lines of the skull called crest lines: more precisely the crest lines of the first skull are matched to the crest lines of the second skull by an iterative closest point algorithm. Then we apply this algorithm to the reference face to obtain the "unknown" face to be reconstructed. The reliability and difficulties of this original technique are then discussed
Iso-surface Extraction in n-D applied to Tracking Feature Curves across Scale
International audienceno abstrac
Iso-surface Extraction in 4D with Applications related to Scale Space
We present a method for extracting iso-surfaces and their intersections in 4D. Our work is a significant extension of the 3D Marching Lines algorithm with new orientation and implementation considerations. As a practical tool, it can be applied to track efficiently space curves, defined by differential invariants, across increasing scale
Following Feature Lines Across Scale
We present an algorithm to extract space curves, defined by differential invariants, at increasing scales. The algorithm uses an extension of the 3D Marching Lines that allows us to search for iso-surfaces and their intersections in spaces of arbitrary dimension. Specifically, we have implemented a 4D extension that we apply to track lines efficiently on iso-surfaces. We show that it automatically finds the connection order of singularities. As an example we visualize the development of parabolic and crest lines across scale
Stability of Corner Points in Scale Space: The Effect of Small Non-Rigid Deformations
International audienceno abstrac