Meet Benjamin Girault, Assistant Professor in Computer Science

Benjamin Girault joined ENSAI in the fall as an Assistant Professor in the Computer Science department. He teaches the Relational Databases and Object-Oriented Programming courses while carrying on his research on graph signal processing.  

Before arriving at ENSAI, Benjamin Girault was a postdoctoral researcher in computer science and a computer scientist at the University of Southern California (USC) in Los Angeles. During these four years, he worked on graph signal processing and on human behavioral intelligence.

He holds a PhD in computer science from École Normale Supérieure de Lyon, on the subject of stationary graph signals (a model for random graph signals). Returning to Rennes after all this time abroad feels like a homecoming, as he was born and educated here until he left for university studies.

Working on Graph Signal Processing

Benjamin Girault’s main research area is called Graph Signal Processing. This area is at the interface between computer science and signal processing.

In computer science, complex discrete structures are modeled by graphs linking entities (vertices) together (using edges).
We can cite transportation networks, computer networks, social networks, or brain neural networks as structures naturally described by graphs. On the other hand, signal processing is the area that analyzes and processes data, usually on regular latices such as time (time series) or space (images), oftentimes through decomposition of those signals.

Graph signal processing combines those two fields into a field where Benjamin Girault is interested in analyzing and processing data (graph signals) lying on discrete structures (graphs) through the decomposition of this data given the graph.

In this field, his main focus is random graph signals, where the statistics of the random graph signals are taken into account to derive efficient decompositions and methods.

On researching and teaching

Part of Benjamin Girault’s attraction to research results from his studies during his time at École Normale Supérieure de Cachan (now École Normale Supérieure de Paris-Saclay), where courses naturally lead students to research.

However, he is also drawn to the process of exploring open questions, finding more open questions to solve, and ultimately advancing science. This curiosity to explore and share knowledge translates to his teaching.

“In my opinion, teaching is an integral part of research, whether it is teaching undergraduate or graduate courses, or advising PhD students. Teaching has always been something I wanted to do”.

A maker

As the saying goes, it can’t be all work and no play… Benjamin Girault has many hobbies.

“A hobby that can be surprising to someone who does not know me is that of “maker”. As far back as I can remember, I have always been drawn to the process of building new things. In today’s terms, this means things like wood working, metal working, 3D printing, or electronics. Nowadays, the online maker community is really large, and building new complex objects such as home furniture, or smart home devices, or just repairing appliances is becoming easier”.

Welcome to ENSAI!

Find out more about Benjamin Girault and research at ENSAI