Julian Tachella
@tachellajulian.bsky.social
260 followers 140 following 68 posts
CNRS research scientist, based at ENS de Lyon I'm interested in AI for imaging inverse problems Looking to hire phds/postdocs! 🇦🇷🇬🇧🇫🇷 Website: https://tachella.github.io/ Deepinverter: https://deepinv.github.io/
Posts Media Videos Starter Packs
Pinned
tachellajulian.bsky.social
🚀 Do you want to learn about self-supervised learning for inverse problems?

▶️ Check out the 3-hour tutorial presented by Mike Davies (University of Edinburgh) and myself (CNRS, ENS Lyon), covering all the recent advances in a unified and simplified framework!

youtube.com/playlist?lis...
Self-Supervised Learning for Inverse Problems - YouTube
Tutorial by Julián Tachella (CNRS, ENS Lyon) & Mike Davies (University of Edinburgh) given at the University of Edinburgh, February 2025.I. "Introduction"II....
youtube.com
tachellajulian.bsky.social
Read more about this new feature in the docs: deepinv.github.io/deepinv/user...

and check out a Jupyter notebook demo: deepinv.github.io/deepinv/auto...

This is a great example of the under-the-hood features that make large-scale training seamless with the library!
Unfolded Algorithms — deepinv 0.3.4 documentation
deepinv.github.io
tachellajulian.bsky.social
The new feature leverages closed-form formulas for computing gradients without storing intermediate steps, only requiring an additional call to the least squares solver.
tachellajulian.bsky.social
DeepInverse provided access to state-of-the-art matrix-free least squares solvers (eg, conjugate gradient, BiCGStab, lsqr, etc), but backproping through their steps required significant memory and slowed down training.
tachellajulian.bsky.social
Many reconstruction models rely on a differentiable least squares solver, such as unfolded networks with proximal steps or reconstruct-anything-model.
tachellajulian.bsky.social
🔎 A focus on the new implicit backprop for least squares solvers (by Minh Hai Nguyen), which unlocks training in large-scale imaging settings:
Unfolded Algorithms — deepinv 0.3.4 documentation
deepinv.github.io
tachellajulian.bsky.social
🚀 New Features:

- Implicit backprop for least squares solvers

- noise statistics for SAR imaging

- Multi-coil MRI coil-map estimation acceleration via CuPy

- RicianNoise model

- Self-supervised super-resolution loss
Unfolded Algorithms — deepinv 0.3.4 documentation
deepinv.github.io
tachellajulian.bsky.social
❔ Uncertainty Quantification
- coverage plots + conformal prediction
🏫 Trainer v2!
tachellajulian.bsky.social
💥 Self-supervised learning
- Noise2Self
- MERLIN for SAR
tachellajulian.bsky.social
📖 Datasets
- PETRIC challenge dataset
- BSD500 dataset
- Calgary MRI dataset
tachellajulian.bsky.social
🚀 More optimizers
- implicit differentiation for linear solvers
- more noisy data fidelities for diffusion
- SPECT preconditioned reconstruction
- phase unwrapping reconstruction
tachellajulian.bsky.social
🖼️ More image priors/regularizers
- latent diffusion models
- general restoration models for PnP
- complex wavelets prior
- weakly convex regularisers
tachellajulian.bsky.social
🌌 Large-scale imaging:
- multi-GPU distributed denoising/reconstruction
- 3D TV/TGV denoising in example
- 3D DRUNet
tachellajulian.bsky.social
🔬 New forward operators
- ultrasound physics
- MRI-NUFFT physics wrapper
- ++ ASTRA integration
- near & far field radar operators
- pytomography wrapper SPECT
- SAR noise models
- multiview operators
- single-pixel spyrit wrapper
- spatial unwrapping operators
- multiscale
tachellajulian.bsky.social
☀️ Just wrapped up the DeepInverse Hackathon!

We had 30+ imaging scientists from all over the world coding during 3 days next to the beautiful Calanques in Marseille, France. It was a great moment to meet new people, discuss science, and code new imaging algorithms!
tachellajulian.bsky.social
For every step, you can either i) use a preexisting {operator,model,dataset} or ii) define a custom one yourself.
tachellajulian.bsky.social
The tutorial, built by @andrewwango.bsky.social, walks you through the main steps of a computational imaging pipeline:

📸 Defining your forward operator
💻 Defining your reconstruction model
🧾 Defining your dataset
tachellajulian.bsky.social
🔬 Are you working in computational imaging or interested in learning?

📖 DeepInverse just released a new 5-minute quickstart tutorial

deepinv.github.io/deepinv/auto...

which gets you started developing AI models for reconstructing images!
tachellajulian.bsky.social
🙏 This is thanks to the contribution of Minh Hai Nguyen
tachellajulian.bsky.social
We also maintain black-box implementations of popular methods like DPS, DDRM, and DiffPIR—ready to use out of the box.
tachellajulian.bsky.social
New Feature in DeepInverse (deepinv.github.io):

🚀 Custom Diffusion Solver Design
DeepInverse now simplifies the process with:

✔ Standard SDEs (VP, VE, etc.)
✔ Pretrained denoisers for multiple noise levels
✔ ODE/SDE solvers (Euler, Heun)
✔ Noisy data fidelity terms for guidance
Redirecting to https://deepinv.github.io/deepinv/
deepinv.github.io
tachellajulian.bsky.social
I will also give a 1-hour talk at NUS (School of Computing) on Wednesday 10 am, see more info here: events.comp.nus.edu.sg/view/24032,

🖇️ code : github.com/tachella/uns...
🖇️ paper: openreview.net/forum?id=ScV...