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

Multiscale Extraction of Features from Medical Images

We present a fast and reliable algorithm, based on iso-surface techniques, to extract differential invariant features at increasing scales. We show that it automatically finds the connection order of singularities, hence it is easy to follow features across scales. As an example, we visualize the orbits of corner points, and compare some criterions to measure their significance