Nicolas Gac

Professeur des universités, université Paris-Saclay
95 %
Libre accès
102
Documents
Identifiants chercheurs

Présentation

After an M.Sc. (2003) and a Ph.D. (2008) degrees, both in signal processing, from the Institut National Polytechnique de Grenoble, I joined in 2009 the University Paris-Saclay first at laboratory L2S as an associate professor and then in 2023 at SATIE as a full professor. I am teaching computer science for embedded systems at the faculty of science. At SATIE, my research interest is focused on algorithm-architecture co-design applied mainly for tomography reconstruction and radio astronomy on multi-GPU servers or FPGA boards.

Detailed CV : https://sdrive.cnrs.fr/s/foKxoD2FaKdwD8Y

Contact :
prenom.nom @ universite-paris-saclay.fr

Laboratoire SATIE / Bureau 2S-73
ENS Paris-Saclay
4 avenue des Sciences / 91 190 Gif-sur-Yvette

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Publications

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X-ray tomography reconstruction accelerated on FPGA through High-Level Synthesis tools

Daouda Diakite , Nicolas Gac

IEEE Transactions on Biomedical Circuits and Systems, 2023, pp.1-14. ⟨10.1109/TBCAS.2023.3258879⟩

Article dans une revue hal-04021970v1
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Fast Grid to Grid Interpolation for Radio Interferometric Imaging

Nicolas Monnier , François Orieux , Nicolas Gac , Cyril Tasse , Erwan Raffin et al.

Astronomy and Computing, 2023, 45, pp.100767. ⟨10.1016/j.ascom.2023.100767⟩

Article dans une revue hal-04264131v2
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Computing Large 2D Convolutions on GPU Efficiently with the im2tensor Algorithm

Mickael Seznec , Nicolas Gac , François Orieux , Alvin Sashala Naik

Journal of Real-Time Image Processing, 2022, 19, pp.1035-1047. ⟨10.1007/s11554-022-01240-0⟩

Article dans une revue hal-03742005v1
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Real-Time Optical Flow Processing on Embedded GPU: a Hardware-Aware Algorithm to Implementation Strategy

Mickaël Seznec , Nicolas Gac , François Orieux , Alvin Sashala Naik

Journal of Real-Time Image Processing, 2022, 19 (2), pp.317-329. ⟨10.1007/s11554-021-01187-8⟩

Article dans une revue hal-03457011v1
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ROHSA: Regularized Optimization for Hyper-Spectral Analysis

Antoine Marchal , Marc-Antoine Miville-Deschênes , François Orieux , Nicolas Gac , Charles Soussen et al.

Astronomy & Astrophysics - A&A, 2019, 626, pp.A101. ⟨10.1051/0004-6361/201935335⟩

Article dans une revue hal-02147300v1
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3D Tomography back-projection parallelization on Intel FPGAs using OpenCL

Maxime Martelli , Nicolas Gac , Alain Mérigot , Cyrille Enderli

Journal of Signal Processing Systems, 2019, 91 (7), pp.1939-8115. ⟨10.1007/s11265-018-1403-6⟩

Article dans une revue hal-01831884v1
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Error-Splitting Forward Model for Iterative Reconstruction in X-ray Computed Tomography and application with Gauss-Markov-Potts prior

Camille Chapdelaine , Ali Mohammad-Djafari , Nicolas Gac , Estelle Parra

IEEE Transactions on Computational Imaging, 2019, 5 (2), pp.317 - 332. ⟨10.1109/TCI.2018.2885432⟩

Article dans une revue hal-01948680v1
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Bayesian 3D X-ray Computed Tomography with a Hierarchical Prior model for Sparsity in Haar Transform domain

Li Wang , Ali Mohammad-Djafari , Nicolas Gac , Mircea Dumitru

Entropy, 2018, Special Issue "Probabilistic Methods for Inverse Problems", ⟨10.3390/e20120977⟩

Article dans une revue hal-01950706v1
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A 3D Bayesian Computed Tomography Reconstruction Algorithm with Gauss-Markov-Potts Prior Model and its Application to Real Data

Camille Chapdelaine , Ali Mohammad-Djafari , Nicolas Gac , Estelle Parra-Denis

Fundamenta Informaticae, 2017, 155 (4), pp.373-405. ⟨10.3233/FI-2017-1591⟩

Article dans une revue hal-01569332v1
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X-ray Computed Tomography using a sparsity enforcing prior model based on Haar transformation in a Bayesian framework

Li Wang , Ali Mohammad-Djafari , Nicolas Gac

Fundamenta Informaticae, 2017, 155 (4), pp.449-480. ⟨10.3233/FI-2017-1594⟩

Article dans une revue hal-01490523v1
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A robust super-resolution approach with sparsity constraint in acoustic imaging

Ning Chu , José Picheral , Ali Mohammad-Djafari , Nicolas Gac

Applied Acoustics, 2014, 76, pp.197-208. ⟨10.1016/j.apacoust.2013.08.007⟩

Article dans une revue hal-00794236v8
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Toward a numerical deshaker for PFS

Frédéric Schmidt , Irina Shatalina , Matthieu Kowalski , Nicolas Gac , Bortolino Saggin et al.

Planetary and Space Science, 2014, 91, pp.45 - 51. ⟨10.1016/j.pss.2013.11.012⟩

Article dans une revue hal-01102830v1
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Algorithmes de reconnaissance NCTR et parallélisation sur GPU

Thomas Boulay , Nicolas Gac , Ali Mohammad-Djafari , Julien Lagoutte

Traitement du Signal, 2013, 6, pp.309-342. ⟨10.3166/TS.30.309-342⟩

Article dans une revue hal-00930953v1
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Experimental results and first 22Na source image reconstruction by two prototype modules in coincidence of a liquid xenon positron emission tomograph for small animal imaging

M.L. Gallin-Martel , Yannick Grondin , Nicolas Gac , Y. Carcagno , L. Gallin-Martel et al.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2012, 682, pp.66-74. ⟨10.1016/j.nima.2012.04.006⟩

Article dans une revue hal-00703776v1
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High Speed 3D Tomography on CPU, GPU, and FPGA

Nicolas Gac , Stéphane Mancini , Michel Desvignes , Dominique Houzet

EURASIP Journal on Embedded Systems, 2008, 2008, http://www.hindawi.com/GetArticle.aspx?doi=10.1155/2008/930250. ⟨10.1155/2008/930250⟩

Article dans une revue hal-00367321v1
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Application d'un cache 2D prédictif à l'accélération de la rétroprojection TEP 2D

Stéphane Mancini , Nicolas Gac , Michel Desvignes , O. Bourrion , O. Rossetto

Traitement du Signal, 2006, 23, pp.Numéro 5-6

Article dans une revue hal-00122552v1
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Prototypage rapide d'un supercalculateur dédié à la radioastronomie

Nicolas Gac , Jean-François Nezan , André Ferrari , Chiara Ferrari , Martin Quinson et al.

L'Interdisciplinarité. Voyages au-delà des disciplines, CNRS Edition, 2023, 978-2-271-13983-2

Chapitre d'ouvrage hal-03704333v1
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Adéquation Algorithme Architecture pour la reconstruction 3D en imagerie médicale TEP

Nicolas Gac

Traitement du signal et de l'image [eess.SP]. Institut National Polytechnique de Grenoble - INPG, 2008. Français. ⟨NNT : ⟩

Thèse tel-00330365v1
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Extension du prototypage rapide pour les pipelines d’imagerie radioastronomique : Simulation avancée multi-nœud HPC

Ophélie Renaud , Sunrise Wang , Nicolas Gac , François Orieux

GRETSI 2025 - 30e Colloque sur le traitement du signal et des images, GRETSI - Groupe de Recherche en Traitement du Signal et des Images, Aug 2025, Strasbourg, France. pp.1-4

Communication dans un congrès hal-05216024v2
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SimSDP, a Rapid Prototyping tool for Radio Astronomy: From NenuFAR Experiments to SKAO-Scale Simulation

Ophélie Renaud , Nicolas Gac , François Orieux , Cedric Dumez-Viou

SiPS 2025 - 38th IEEE Workshop on Signal Processing Systems, Nov 2025, Hong Kong, China. pp.1-5

Communication dans un congrès hal-05260888v2
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Scalable Hydrodynamics on multiple Field-Programmable Gate Arrays (FPGAs)

François-Xavier Mordant , Charles Prouveur , Pascal Tremblin , Nicolas Gac

SC Workshops '25: Workshops of the International Conference for High Performance Computing, Networking, Storage and Analysis, Nov 2025, St Louis, United States. pp.1832-1841, ⟨10.1145/3731599.3767545⟩

Communication dans un congrès hal-05390519v1
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A practical HW-aware NAS flow for AI vision applications on embedded heterogeneous SoCs

Agathe Archet , Nicolas Ventroux , Nicolas Gac , François Orieux

18th Workshop on Design and Architectures for Signal and Image Processing (DASIP 2025), Jan 2025, Barcelone, Spain. pp.43-56, ⟨10.1007/978-3-031-87897-8_4⟩

Communication dans un congrès hal-04869471v1
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Dark-era : Dataflow Algorithm aRchitecture co-design of SKA pipeline for Exascale Radio Astronomy

Nicolas Gac , Ophélie Renaud

SaLF 2025 - 11th Annual conference on Science At Low Frequencies, Dec 2025, Orléans, France

Communication dans un congrès hal-05430702v1
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An Initial Framework for Prototyping the Radio-Interferometric Imaging Pipelines

Sunrise Wang , Nicolas Gac , Hugo Miomandre , Jean-François Nezan , Karol Desnos et al.

DASIP 2024 - Workshop on Design and Architectures for Signal and Image Processing, HiPEAC, Jan 2024, Munich, Germany. pp 56-67, ⟨10.1007/978-3-031-62874-0_5⟩

Communication dans un congrès hal-04361151v3

Projet ANR Dark-era : Adéquation Algorithme Architecture (A3) pour la radioastronomie

Nicolas Gac

Colloque national du GDR SoC2, Jun 2024, Toulouse, France

Communication dans un congrès hal-04611829v1
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Energy-efficient use of an embedded heterogeneous SoC for the inference of CNNs

Agathe Archet , Nicolas Ventroux , Nicolas Gac , François Orieux

2023 26th Euromicro Conference on Digital System Design (DSD), Sep 2023, Durrës, Albania

Communication dans un congrès hal-04148582v1
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Exploration d'architectures de réseaux de neurones pour la segmentation sémantique d'images aériennes

Agathe Archet , François Orieux , Nicolas Ventroux , Nicolas Gac

GRETSI 2023 - XXIXème Colloque Francophone de Traitement du Signal et des Images, Aug 2023, Grenoble, France

Communication dans un congrès hal-04148565v1
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Embedded AI performances of Nvidia's Jetson Orin SoC series

Agathe Archet , Nicolas Gac , François Orieux , Nicolas Ventroux

17ème Colloque National du GDR SOC2, Jun 2023, Lyon, France

Communication dans un congrès hal-04186977v1
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FPGA implementation of 2D Convolution using OneAPI and OpenCL

Daouda Diakite , Nicolas Gac

16ème Colloque National du GDR SOC2, Jun 2022, Strasbourg, France

Communication dans un congrès hal-03695100v1
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Premiers résultats de comparaison des outils oneAPI et OpenCL pour la convolution 2D sur FPGA

Daouda Diakite , Nicolas Gac

GRETSI 2022 - XXIIXème Colloque Francophone de Traitement du Signal et des Images, Sep 2022, Nancy, France

Communication dans un congrès hal-03695087v1
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MobileFlow : modèle et mise en œuvre pour une inférence de flot optique efficace

Mickael Seznec , Agathe Archet , Nicolas Gac , François Orieux , Alvin Sashala Naik

GRETSI 2022 - XXIIXème Colloque Francophone de Traitement du Signal et des Images, Sep 2022, Nancy, France

Communication dans un congrès hal-03695558v2
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Multi-core multi-node parallelization of the radio interferometric imaging pipeline DDFacet

Nicolas Monnier , David Guibert , Cyril Tasse , Nicolas Gac , François F. Orieux et al.

SiPS22-IEEE Workshop on Signal Processing Systems, Nov 2022, Rennes, France. ⟨10.1109/sips55645.2022.9919239⟩

Communication dans un congrès hal-03729202v1
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Fast Sky to Sky Interpolation for Radio Interferometric Imaging

Nicolas Monnier , François Orieux , Nicolas Gac , Cyril Tasse , Erwan Raffin et al.

29th IEEE International Conference on Image Processing (ICIP 2022), Oct 2022, Bordeaux, France. ⟨10.1109/ICIP46576.2022.9897317⟩

Communication dans un congrès hal-03725824v2
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Interpolation Rapide Sky to Sky pour l'Imagerie Radio Interférométrique

Nicolas Monnier , François F. Orieux , Nicolas Gac , David Guibert , Cyril Tasse et al.

GRETSI 2022 - XXIIXème Colloque Francophone de Traitement du Signal et des Images, Sep 2022, Nancy, France

Communication dans un congrès hal-03696220v1
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Memory prefetching for tomography acceleration on FPGAs through HLS tools

Daouda Diakite , Nicolas Gac

15ème Colloque National du GDR SOC2, Jun 2021, Rennes, France

Communication dans un congrès hal-03240542v1
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OpenCL FPGA Optimization guided by memory accesses and roofline model analysis applied to tomography acceleration

Daouda Diakite , Nicolas Gac , Maxime Martelli

31st International Conference on Field Programmable Logic and Applications (FPL), Aug 2021, Dresden (virtual), Germany. pp.109-114, ⟨10.1109/FPL53798.2021.00026⟩

Communication dans un congrès hal-03226257v2
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An efficiency-driven approach for real-time optical flow processing on parallel hardware

Mickael Seznec , Nicolas Gac , F. Orieux , A. Sashala Naik

IEEE International Conference on Image Processing (ICIP’2020), Oct 2020, Abu Dhabi, United Arab Emirates. ⟨10.1109/icip40778.2020.9191164⟩

Communication dans un congrès hal-02604755v1
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Data distribution on a multi-GPU node for TomoBayes CT reconstruction

Mohammed Chghaf , Nicolas Gac

The 26th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications, Aug 2020, Inconnu, South Korea

Communication dans un congrès hal-02586239v4
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An OpenCL pipeline implementation on Intel FPGA for 3D backprojection

Daouda Diakite , Maxime Martelli , Nicolas Gac

6th International Conference on Image Formation in X-Ray Computed Tomography, Aug 2020, Regensburg, Germany

Communication dans un congrès hal-02500994v2

Student Session: Data distribution on a multi-GPU node for TomoBayes CT reconstruction

Mohammed Chghaf , Nicolas Gac

2020 IEEE 26th International Conference on Embedded and Real-Time Computing Systems and Applications (RTCSA), Aug 2020, Gangnueng, South Korea. pp.1-2, ⟨10.1109/RTCSA50079.2020.9203709⟩

Communication dans un congrès hal-04539697v1
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GPU Acceleration : OpenACC for Radar Processing Simulation

Maxime Martelli , Cyrille Enderli , Nicolas Gac , Antoine Vermesse , Alain Mérigot

International Radar Conference, Sep 2019, Toulon, France. pp.1-6, ⟨10.1109/RADAR41533.2019.171296⟩

Communication dans un congrès hal-02129441v1
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Multi-streaming and multi-GPU optimization for a matched pair of Projector and Backprojector

Nicolas Georgin , Camille Chapdelaine , Nicolas Gac , Ali Mohammad-Djafari , Estelle Parra-Denis

The 2019 International Conference on Fully Three-Dimensional Image Reconstruction in Radiology and Nuclear Medicine, Jun 2019, Philadelphie, PA, United States. ⟨10.1117/12.2534108⟩

Communication dans un congrès hal-02070223v1
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Variational Bayesian approach in model-based iterative reconstruction for 3D X-ray computed tomography with Gauss-Markov-Potts prior

Camille Chapdelaine , Ali Mohammad-Djafari , Nicolas Gac , Estelle Parra-Denis

MaxEnt 2019 : Workshop on Bayesian Inference and Maximum Entropy Methods in Science and Engineering, Jun 2019, Garching/Munich, Germany. ⟨10.3390/proceedings2019033004⟩

Communication dans un congrès hal-02132706v1
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Accélération sur GPU d'une simulation radar avec OpenACC

Maxime Martelli , Cyrille Enderli , Nicolas Gac , Antoine Vermesse , Alain Mérigot

GRETSI 2019 - XXVIIème Colloque francophone de traitement du signal et des images, Aug 2019, Lille, France

Communication dans un congrès hal-02147363v1
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New GPU implementation of Separable Footprint (SF) Projector and Backprojector : first results

Camille Chapdelaine , Nicolas Gac , Ali-Mohammad Djafari , Estelle Parra-Denis

The Fifth International Conference on Image Formation in X-Ray Computed Tomography, May 2018, Salt Lake City, United States. pp.314-317

Communication dans un congrès hal-01745746v1
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Harnessing FPGAs potential with OpenCL

Maxime Martelli , Nicolas Gac , Alain Mérigot , Cyrille Enderli

13ème Colloque nationale du GDR SoC/SiP, Jun 2018, Paris, France

Communication dans un congrès hal-01841029v1
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A Study on Convolution Operator Using Half Precision Floating Point Numbers on GPU for Radioastronomy Deconvolution

Mickael Seznec , Nicolas Gac , André Ferrari , François Orieux

IEEE International Workshop on Signal Processing Systems (SiPS 2018), Oct 2018, Le Cap, South Africa. ⟨10.1109/sips.2018.8598342⟩

Communication dans un congrès hal-01837982v1
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Bayesian Inference with Error Variable Splitting and Sparsity Enforcing Priors for Linear Inverse Problems

Ali Mohammad-Djafari , Mircea Dumitru , Camille Chapdelaine , Nicolas Gac

26th European Signal Processing Conference (EUSIPCO 2018), Sep 2018, Rome, Italy. ⟨10.23919/eusipco.2018.8553335⟩

Communication dans un congrès hal-01837986v1
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Comparaison des performances d’algorithmes itératifs bayésiens basés sur trois classes de modèles a priori parcimonieux appliqués à la reconstruction tomographique

Mircea Dumitru , Li Wang , Nicolas Gac , Ali Mohammad-Djafari

26eme Colloque GRETSI Traitement du Signal & des Images, GRETSI 2017, Sep 2017, Juans-Les-Pins, France

Communication dans un congrès hal-01569349v1
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Joint Reconstruction and Segmentation of Real 3D Data in Computed Tomography thanks to a Gauss-Markov-Potts Prior Model,

Camille Chapdelaine , Ali Mohammad-Djafari , Nicolas Gac , Estelle Parra-Denis

Fully 3D, Jun 2017, Xian, China. pp.810-813

Communication dans un congrès hal-01569301v1
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A joint segmentation and reconstruction algorithm for 3D Bayesian Computed Tomography using Gaus-Markov-Potts Prior Model

Camille Chapdelaine , Ali Mohammad-Djafari , Nicolas Gac , Estelle Parra-Denis

The 42nd IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP 2017), Mar 2017, New Orleans, United States

Communication dans un congrès hal-01588443v1
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Reconstruction 3D en tomographie à rayons X à l'aide d'un modèle a priori hiérarchique utilisant la transformation de Haar

Li Wang , Nicolas Gac , Ali Mohammad-Djafari

26eme Colloque GRETSI Traitement du Signal & des Images, GRETSI 2017, Sep 2017, Juan-Les-Pins, France

Communication dans un congrès hal-01567888v1
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Bayesian X-ray Computed Tomography using a Three-level Hierarchical Prior Model

Li Wang , Ali Mohammad-Djafari , Nicolas Gac

AIP Conference, Bayesian inference and maximum entropy methods in science and engineering (Maxent 2016), Jul 2016, Gent, Belgium. ⟨10.1063/1.4985361⟩

Communication dans un congrès hal-01403790v1
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3D Tomography parallelization on FPGAs via HLS tools

Maxime Martelli , Nicolas Gac , Alain Mérigot , Cyrille Enderli

DASIP, Sep 2017, dresden, Germany. pp.1-6, ⟨10.1109/DASIP.2017.8122119⟩

Communication dans un congrès hal-01569320v1
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X-ray computed tomography simultaneous image reconstruction and contour detection using a hierarchical markovian model

Li Wang , Ali Mohammad-Djafari , Nicolas Gac

The 42nd IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP 2017), Mar 2017, New Orleans, United States. pp.6070-6074, ⟨10.1109/ICASSP.2017.7953322⟩

Communication dans un congrès hal-01490508v1
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3D X-ray Computed Tomography reconstruction using sparsity enforcing Hierarchical Model based on Haar Transformation

Li Wang , Ali Mohammad-Djafari , Nicolas Gac , Mircea Dumitru

The 2017 International Conference on Fully Three-Dimensional Image Reconstruction in Radiology and Nuclear Medicine, Jun 2017, Xi'an, China. pp.295-298

Communication dans un congrès hal-01490554v1
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Bayesian method with sparsity enforcing prior of dual-tree complex wavelet transform coefficients for X-ray CT image reconstruction

Li Wang , Ali Mohammad-Djafari , Nicolas Gac

25th European Signal Processing Conference (EUSIPCO 2017), Aug 2017, Kos island, Greece. ⟨10.23919/eusipco.2017.8081253⟩

Communication dans un congrès hal-01567875v1
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Unsupervised sparsity enforcing iterative algorithms for 3D image reconstruction in X-ray computed tomography

Mircea Dumitru , Nicolas Gac , Li Wang , Ali Mohammad-Djafari

The 2017 International Conference on Fully Three-Dimensional Image Reconstruction in Radiology and Nuclear Medicine, Jun 2017, Xi'an, China. pp.359-362

Communication dans un congrès hal-01568325v1
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Performance comparison of Bayesian iterative algorithms for three classes of sparsity enforcing priors with application in computed tomography

Mircea Dumitru , Wang Li , Nicolas Gac , Ali Mohammad-Djafari

2017 IEEE International Conference on Image Processing, Sep 2017, Beijing, China

Communication dans un congrès hal-01568337v1
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Model selection in the sparsity context for inverse problems in Bayesian framework

Mircea Dumitru , Li Wang , Ali Mohammad-Djafari , Nicolas Gac

37th International Workshop on Bayesian Inference and Maximum Entropy Methods in Science and Engineering, Jul 2017, Jarinu, Brazil. ⟨10.1007/978-3-319-91143-4_15⟩

Communication dans un congrès hal-01568318v1
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A Student-t based sparsity enforcing hierarchical prior for linear inverse problems and its efficient Bayesian computation for 2D and 3D Computed Tomography

Ali Mohammad-Djafari , Li Wang , Nicolas Gac , Folkert Bleichrodt

International traveling workshop on interactions between sparse models and technology, Aug 2016, AALBORG, Denmark

Communication dans un congrès hal-01403787v1
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Computed tomography reconstruction based on a hierarchical model and variational Bayesian method

Li Wang , Ali Mohammad-Djafari , Nicolas Gac , Mircea Dumitru

IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Mar 2016, Shanghai, China. pp.883-887, ⟨10.1109/ICASSP.2016.7471802⟩

Communication dans un congrès hal-01403784v1
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A hierarchical variational Bayesian approximation approach in acoustic imaging

Ning Chu , Ali Mohammad-Djafari , Nicolas Gac , José Picheral

34th International Workshop on Bayesian Inference and Maximun Entropy Methods in Science and Engineering (MaxEnt'14), Sep 2014, Amboise, France. pp.572 - 579, ⟨10.1063/1.4906024⟩

Communication dans un congrès hal-01103784v1
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Bayesian 3D X-ray computed tomography image reconstruction with a scaled Gaussian mixture prior model

Li Wang , Nicolas Gac , Ali Mohammad-Djafari

34th International Workshop on Bayesian Inference and Maximun Entropy Methods in Science and Engineering (MaxEnt'14), Sep 2014, Amboise, France. pp.556-563, ⟨10.1063/1.4906022⟩

Communication dans un congrès hal-01338706v1
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Aero-acoustics source separation with sparsity inducing priors in the frequency domain

Olivier Schwander , José Picheral , Nicolas Gac , Ali-Mohammad Djafari , Daniel Blacodon

34th International Workshop on Bayesian Inference and Maximun Entropy Methods in Science and Engineering (MaxEnt'14), Sep 2014, Amboise, France. pp.422 - 431, ⟨10.1063/1.4906006⟩

Communication dans un congrès hal-01103779v1
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A variational Bayesian approximation approach via a sparsity enforcing prior in acoustic imaging

Ning Chu , Ali Mohammad-Djafari , Nicolas Gac , José Picheral

WIO 2014, Jul 2014, Neuchâtel, Switzerland. pp.1 - 4, ⟨10.1109/WIO.2014.6933297⟩

Communication dans un congrès hal-01103751v1
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Convolution Models with Shift-invariant kernel based on Matlab-GPU platform for Fast Acoustic Imaging

Ning Chu , Nicolas Gac , José Picheral , Ali Mohammad-Djafari

ISAV 2014, Dec 2014, Tehran, Iran

Communication dans un congrès hal-01103819v1
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A simple and efficient super-short-scan algorithm of fan-beam reconstruction for multiple circular trajectories: solution towards the truncated data

Long Chen , Thomas Rodet , Nicolas Gac

The Third International Conference on Image Formation in X-Ray Computed Tomography , Jun 2014, Salt Lake City, United States. pp.212-215

Communication dans un congrès hal-01403846v1
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2D convolution model using (in)variant kernels for fast acoustic imaging

Ning Chu , Nicolas Gac , José Picheral , Ali Mohammad-Djafari

5 th Berlin Beamforming Conference 2014, Feb 2014, Berlin, Germany. 15 p

Communication dans un congrès hal-01083451v1
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A penalized weighted least-squares image reconstruction based on scatter correction methods for X-ray CT

Long Chen , Thomas Rodet , Nicolas Gac

2013 IEEE Nuclear Science Symposium and Medical Imaging Conference, Oct 2013, Seoul, South Korea. pp.2

Communication dans un congrès hal-00843508v1
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High-Dimensional Range Profile Geometrical Visualization and Performance Estimation of Radar Target Classification via a Gaussian Mixture Model

Thomas Boulay , Ali Mohammad-Djafari , Nicolas Gac , Julien Lagoutte

Geometric Science of Information, Aug 2013, Paris, France. pp.829-836, ⟨10.1007/978-3-642-40020-9_93⟩

Communication dans un congrès hal-00931023v1
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An efficient variational Bayesian inference approach via Studient's-t priors for acoustic imaging in colored noises

Ning Chu , Ali Mohammad-Djafari , José Picheral , Nicolas Gac

POMA - ICA 2013, Jun 2013, Montreal, Canada. 055031 (9p.)

Communication dans un congrès hal-00865786v2
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Analytical model and spectral correction of vibration effects on Fourier transform spectrometer

I. Shatalina , Frederic Schmidt , B. Saggin , Nicolas Gac , Matthieu Kowalski et al.

SPIE Remote sensing 2013, Sep 2013, Dresden, Germany. pp.88900S-88900S-9, ⟨10.1117/12.2028632⟩

Communication dans un congrès hal-00930996v1
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A Fuzzy-Logic based non cooperative target recognition

Thomas Boulay , Julien Lagoutte , Ali Mohammad-Djafari , Nicolas Gac

Signal Image Technology and Internet Based Systems 2012, Nov 2012, Naples, Italy. pp.410-145, ⟨10.1109/SITIS.2012.66⟩

Communication dans un congrès hal-00778560v1
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Accélération sur serveur multi-GPUs de la reconstruction 3D d'une mousse de nickel par méthodes itératives algébriques régularisées

Nicolas Gac , Alexandre Vabre , Ali Mohammad-Djafari , Fanny Buyens

23ème colloque GRETSI sur le traitement du signal et des images, Sep 2011, Bordeaux, France. pp.id455

Communication dans un congrès hal-00616941v1
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Algorithmes de Reconnaissance Non Coopérative de Cibles et implémentation sur GPU

Thomas Boulay , Nicolas Gac , Ali Mohammad-Djafari , Julien Lagoutte

GRETSI, Sep 2011, Bordeaux, France. pp.ID146

Communication dans un congrès hal-00617103v1
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Multi GPU parallelization of 3D bayesian CT algorithm and its application on real foam reonconstruction with incomplete data set

Nicolas Gac , Alexandre Vabre , Ali Mohammad-Djafari

Forum on recent developments in Volume Reconstruction techniques applied to 3D fluid and solid mechanics, Nov 2011, Poitiers, France. pp.35-38

Communication dans un congrès hal-00658653v1
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GPU implementation of a 3D bayesian CT algorithm and its application on real foam reconstruction

Nicolas Gac , Alexandre Vabre , Ali Mohammad-Djafari , Asier Rabanal , Fanny Buyens

The First International Conference on Image Formation in X-Ray Computed Tomography, Jun 2010, Salt Lake City, United States. pp.151-155

Communication dans un congrès hal-00504740v2
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Parallélisation sur GPU d'un algorithme de reconstruction 3D bayésien en tomographie X.

Nicolas Gac , Alexandre Vabre , Ali Mohammad-Djafari , Fanny Buyens , Samuel Legoupil

Développement d'applications de calcul intensif sur carte graphique pour l'imagerie moléculaire, May 2009, Obernai, France

Communication dans un congrès hal-00504759v1
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A Hardware Projector/Backprojector Pair for 3D PET Reconstruction

Nicolas Gac , Stéphane Mancini , Michel Desvignes , Florian de Boissieu , Anthonin Reilhac

SPIE Medical Imaging 2008, Feb 2008, San Diego, Californie, United States. pp.69132O, ⟨10.1117/12.770588⟩

Communication dans un congrès hal-00232621v1
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Algorithm Architecture Adequacy for High Speed 3D Tomography

Nicolas Gac , Stéphane Mancini , Michel Desvignes , Dominique Houzet

DASIP 2007 - Workshop on Design and Architectures for Signal and Image Processing, Nov 2007, Grenoble, France

Communication dans un congrès hal-00175732v1
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Hardware/software 2D-3D backprojection on a SoPC platform

Nicolas Gac , Stéphane Mancini , Michel Desvignes

ACM Symposium on Applied Computing, Apr 2006, Dijon, France. pp.222 - 228

Communication dans un congrès hal-00102903v1
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2D backprojection on a SOPC platform : first results

Stéphane Mancini , Nicolas Gac , Michel Desvignes

13 ème Forum Recherche en Génie Biologique et Médica, 2005, Nancy, France

Communication dans un congrès hal-00102911v1
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Rétroprojection 2D sur plateforme SOPC

Stéphane Mancini , Nicolas Gac , Michel Desvignes

GRETSI'05, Sep 2005, Louvain-la-neuve, Belgique. pp.783-786

Communication dans un congrès hal-00102907v1
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Etude d'un cache 2D adaptatif et prédictif pour le traitement d'image

Stéphane Mancini , Nicolas Gac , Michel Desvignes

Journées Francophones en Adéquation Algorithme Architecture, Jan 2005, Dijon, France. pp.JFAAA 2005

Communication dans un congrès hal-00102913v1
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Detection and Speech/Sound Segmentation in a Smart Room Environment

Michel Vacher , Dan Istrate , Jean-François Serignat , Nicolas Gac

Trends in Speech Technology, The 3rd International Conference on Speech Technology and Human-Computer Dialogue, IEEE, SpeD2005, May 2005, Cluj, Romania

Communication dans un congrès hal-01092602v1
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SimSDP, a Rapid Prototyping tool for Radio Astronomy: From NenuFAR Experiments to SKAO-Scale Simulation

Ophélie Renaud , Nicolas Gac , François Orieux , Cedric Dumez-Viou

SaLF 2025 - 11th Annual conference on Science At Low Frequencies, Dec 2025, Orleans (France), France. pp.1-1

Poster de conférence hal-05406207v1
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Les télélescopes SKA

Nicolas Monnier , Nicolas Gac , François Orieux

Fête de la science, Oct 2022, Saclay, France.

Poster de conférence hal-03825850v1
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Fast Sky to Sky Interpolation for Radio Interferometric Imaging

Nicolas Monnier , François Orieux , Nicolas Gac , Cyril Tasse , Erwan Raffin et al.

29th IEEE International Conference on Image Processing (ICIP 2022), Oct 2022, Bordeaux, France. IEEE, 2022 IEEE International Conference on Image Processing (ICIP), 2022, ⟨10.1109/ICIP46576.2022.9897317⟩

Poster de conférence hal-04696638v1
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Dataflow Algorithm aRchitecture co-design of SKA pipeline for Exascale Radio Astronomy

Daniel Charlet , Karol Desnos , Mickaël Dardaillon , André Ferrari , Chiara Ferrari et al.

ISC High Performance 2021, Jun 2021, Virtual conference, France. pp.1

Poster de conférence hal-03233205v2
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A new convolutions algorithm to leverage tensor cores

Mickael Seznec , Nicolas Gac , F. Orieux , A. Sashala Naik

GPU Technology Conference (GTC), May 2020, Silicon Valley, United States

Poster de conférence hal-02605077v1
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An OpenCL design for tomographic reconstruction on FPGA. Innovate Europe Design Contest Winners

Maxime Martelli , Mickael Seznec , Nicolas Heemeryck , Nicolas Gac

27th international conference on field programmable logic and applications, Sep 2017, Ghent, Belgium. 2017

Poster de conférence hal-01851828v1
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Parallelization on a 8-GPU server of iterative 3D reconstruction algorithm for dental X-ray tomography

Long Chen , Nicolas Gac , Thomas Rodet , Colombe Maury

PUMPS summer school, Jul 2012, Barcelone, Spain

Poster de conférence hal-01851992v1
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Implémentation et optimisation du calcul sur GPUs FERMI et non FERMI de la distance euclidienne entre des profils distance obtenus à partir de données radar dans le contexte NCTR

Thomas Boulay , Nicolas Gac , Ali Mohammad-Djafari , Julien Lagoutte

Ecole d’été GPU, Jun 2011, Grenoble, France

Poster de conférence hal-01851986v1
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[OMTE 2008/2009] GPU speed-up of a 3D Bayesian CT algorithm : reconstruction of a real foam

Nicolas Gac , Asier Rabanal , Alexandre Vabre , Ali Mohammad-Djafari

Forum Digiteo, Oct 2010, Palaiseau, France

Poster de conférence hal-01851994v1
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French SKA White Book - The French Community towards the Square Kilometre Array

F. Acero , J. -T. Acquaviva , R. Adam , N. Aghanim , Mark G. Allen et al.

C. Ferrari; G. Lagache; M.-A. Miville-Deschenes; L. Montier; E. Josselin; N. Vilmer; P. Zarka; S. Corbel; S. Vergani; S. Lambert; G. Theureau; S. Bosse; A. Ferrari; S. Gauffre; G. Marquette; J.-M. Martin; B. Semelin; M. Alves; K. Ferrière. 2018, ⟨10.48550/arXiv.1712.06950⟩

Ouvrages hal-01686223v1