TEMICS Research team
Digital image processing, modeling and communication
- Leader : Christine Guillemot
- Research center(s) : CRI Rennes - Bretagne Atlantique
- Field : Perception, Cognition, Interaction
- Theme : Vision, Perception and Multimedia Understanding
- Partner(s) : CNRS,Université Rennes 1
- Collaborator(s) : U. RENNES 1, CNRS, INRIA, INSA RENNES, CENTRALESUPELEC, ENS RENNES, INSTITUT MINES-TELECOM, UBS
Team presentationThe objectives of the project are to develop concepts and tools in the areas of modelling, coding, communication and watermarking of image and video information handled in multimedia communication.
Research themesMore specifically, our research activities address the following issues:
- interaction with content and navigation within a 3D representation of the scene captured by a monocular video sequence;
- image and video source representations that would be compact and robust to noise (packet losses, bit corruption) present on IP or wireless network infrastructures;
- watermarking for protection against illegal copies and for authentication.
In order to address the above issues, the project activities are structured in three main research themes :
- Analysis and modelling of video sequencess.
This first research line aims at studying suited models of representation for
image and video sources. When targeting interaction with the content, a phase
of analysis is required. This phase consists in segmenting video objects,
in extracting their main attributes (motion, texture, shape, orientation,
illumination, ...). Navigating within the scene captured by the video
sequence also requires the construction of a 3D model of the scene.
The models and attributes extracted must be easy to manipulate. When
targeting communication on narrow-band error-prone environments,
the representations of these models must be compact and resilient to
In order to allow for an easy
adaptation to variable constraints linked to the communication channel or to
the application, the specified models must be well suited for a granular
and hierarchical representation.
- Joint source and channel coding.
The advent of the Internet and of wireless communications, often
characterised by narrow-band, error and/or loss prone and heterogeneous
channels, is creating challenging problems in the area of video coding.
Design principles prevailing so far and stemming from Shannon's
source and channel separation theorem are being re-considered.
To minimize the impact of the transmission noise on the quality
of the reconstructed signal in order to optimize the end-to-end
quality of the transmission chain requires to abandon the
separation theorem and to consider instead joint source and channel
These solutions, considered as viable alternatives for
reliable communication over noisy and/or lossy channels,
go from a simple joint adjustment of source and channel
coding rates to the channel conditions, to a complete re-design
of the different operators of a coding scheme. The problematic
endorses various characteristics according to the type of
channel considered, its loss or error models and according
to the application configuration (e.g. real-time interactive or streaming).
Watermarking and information hiding refers to nearly invisible embedding of
a message within a host signal (text, audio, images or video).
It has gained considerable attention in the recent years as
a potential solution for a wide range of applications
protection, authentication, and steganography.
The watermarking problem can be viewed as a problem of communication
over a noisy transmission environment.
In the spirit of a communication problem one
then seeks the maximum rate of reliable transmission over any hiding and
The scientific background of TEMICS in both analysis and joint source and
channel coding allows to apprehend efficiently this problematic.
International and industrial relationsThe application domain is multimedia communication over IP and wireless networks with their multiple needs in terms of compression, of robust transmission and of advanced functionalities such as navigation, protection and authentication. In this application domain we have industrial collaborations with Thomson Multimedia, France Telecom, Celar We are also involved in national collaborative projects (RNRT COHRAINTE, COSOCATI, OSIAM, V2NET, VISI) and in European collaborative projects (IST-SONG, IST-OPENISE and IST-OZONE). The TEMICS project has also several accademical collaborations on a national level (L2S, I3S) and on an international level (University of illinois at Chicago, Université Catholique de Louvain-La-Neuve).
Keywords: Temics Videocommunication Image sequence Coding Multimedia Numerical television Videowatch Segmentation Motion Projective geometry Quantification Increased reality Networks Internet Quality of servic