Raphaël Rème

Postdoctoral Researcher  ·  Institut Pasteur, Paris  ·  Biological Analysis Unit

I work on multiple object tracking (MOT) in biological microscopy images — in particular fluorescence imaging of neurons in small model organisms such as Hydra vulgaris. My research combines Bayesian filtering, optical flow, and self-supervised visual learning to build robust, accurate tracking pipelines for dense biological scenes.

Raphaël Rème
Journal articles
Automatic Monitoring of Neural Activity with Single-Cell Resolution in Behaving Hydra
Alison Hanson*, Raphael Reme*, Noah Telerman*, Wataru Yamamoto, Jean-Christophe Olivo-Marin, Thibault Lagache, Rafael Yuste
Scientific Reports, 2024
2024
Conference papers
SINETRA: A Versatile Framework for Evaluating Single Neuron Tracking in Behaving Animals
Raphael Reme*, Alasdair Newson, Elsa Angelini, Jean-Christophe Olivo-Marin, Thibault Lagache
IEEE 22nd International Symposium on Biomedical Imaging (ISBI), 2025
2025
Particle Tracking in Biological Images with Optical-Flow Enhanced Kalman Filtering
Raphael Reme*, Alasdair Newson, Elsa Angelini, Jean-Christophe Olivo-Marin, Thibault Lagache
IEEE International Symposium on Biomedical Imaging (ISBI), 2024
2024
Tracking Intermittent Particles with Self-Learned Visual Features
Raphael Reme*, Victor Piriou, Alison Hanson, Rafael Yuste, Alasdair Newson, Elsa Angelini, Jean-Christophe Olivo-Marin, Thibault Lagache
IEEE 20th International Symposium on Biomedical Imaging (ISBI), 2023
2023
To be published
Integrating Visual Features in Multiple Hypothesis Tracking through Self-Supervised Learning
Raphael Reme*, Alasdair Newson, Elsa Angelini, Jean-Christophe Olivo-Marin, Thibault Lagache
Accepted — IEEE International Symposium on Biomedical Imaging (ISBI) 2026
PDF To appear Code
2026

* Equal contribution.

Integrating Optical Flow within a Bayesian Framework for Multiple Object Tracking in Biological Imaging. Application to Neuron Tracking in Hydra.

Institut Pasteur & Télécom Paris  ·  2022–2025  ·  Supervisors: T. Lagache, J.-C. Olivo-Marin, A. Newson, E. Angelini

Understanding neuronal activity in behaving animals requires accurate tracking of large neuronal populations over time. In small model organisms such as Hydra vulgaris, calcium imaging enables the monitoring of hundreds of neurons simultaneously, but reliable tracking remains a major challenge due to strong body deformations, dense neuronal populations, and the intermittent detectability of neurons. This thesis develops three complementary contributions: (1) SINETRA, a versatile simulator generating annotated 2D/3D fluorescence videos for benchmarking neuron tracking algorithms; (2) KOFT / KOFT-MHT, Kalman-based trackers augmented with optical flow as a second sensor, embedded in a full Bayesian Multiple Hypothesis Tracking framework; (3) VEMC², a tracklet stitching method combining self-supervised visual features with positional cues to reconnect fragmented trajectories. The methods achieve substantial improvements in tracking accuracy, including a first-place ranking on the Cell Tracking Challenge Cell Linking Benchmark.

Keywords: Multiple Object Tracking · Bayesian models · Optical flow · Self-supervised learning · Fluorescence imaging · Calcium imaging · Hydra vulgaris
Download thesis PDF

ByoTrack

Python library for biological object tracking. Implements classic and state-of-the-art detection, segmentation and tracking methods.

🏆 1st — CTC Cell Linking Benchmark

Torch-KF

PyTorch implementation of Kalman filters with batch processing, CPU/GPU parallelisation, and support for smoothing.

Pylapy

Fast and Pythonic linear assignment problem solver.

Tps / Torch-Tps

Fast Thin Plate Spline implementation based on NumPy or PyTorch. Scikit-Learn-like API with CPU/GPU support.

Expyrun

Offline management of reproducible research experiments from YAML configuration files, with isolated source and dependencies.

PhD, Computer Vision & Tracking
Institut Pasteur / Télécom Paris, Paris
Biological object tracking. Application to Hydra vulgaris neurons.
2022 – 2025
MSc, Mathematics, Vision, Learning (MVA)
Institut Polytechnique de Paris
Graduated with Highest Honors.
2020 – 2021
MSc Engineering (Embedded Systems & Data Science)
Télécom Paris
2017 – 2021
Address
Institut Pasteur, 25 rue du Docteur Roux
75015 Paris, France