activity
20122026
most citedHessian Schatten-Norm Regularization for Linear Inverse Problems

174 citations · 296 across the 15 of their papers we have counts for

collaborators

21 papers

cs.LG2026

GeoPair: Geometry-Preserving Cross-Layer Factorization for Training-Free Transformer Compression

Baher Mohammad, Ammar Ali, Stamatios Lefkimmiatis

Transformer architectures exhibit cross-layer redundancies, yet post-training compression pipelines typically optimize layers in isolation or rely on heuristic grouping strategies…

cs.LG2026

COMPOT: Calibration-Optimized Matrix Procrustes Orthogonalization for Transformers Compression

Denis Makhov, Dmitriy Shopkhoev, Magauiya Zhussip +3

Post-training compression of Transformer models commonly relies on truncated singular value decomposition (SVD). However, enforcing a single shared subspace can degrade accuracy ev…

cs.LG2026

ROCKET: Rapid Optimization via Calibration-guided Knapsack Enhanced Truncation for Efficient Model Compression

Ammar Ali, Baher Mohammad, Denis Makhov +3

We present ROCKET, a training-free model compression method that achieves state-of-the-art performance in comparison with factorization, structured-sparsification and dynamic compr…

cs.SD2025

Speak, Edit, Repeat: High-Fidelity Voice Editing and Zero-Shot TTS with Cross-Attentive Mamba

Baher Mohammad, Magauiya Zhussip, Stamatios Lefkimmiatis

We introduce MAVE (Mamba with Cross-Attention for Voice Editing and Synthesis), a novel autoregressive architecture for text-conditioned voice editing and high-fidelity text-to-spe…

cs.CL2025

CoSpaDi: Compressing LLMs via Calibration-Guided Sparse Dictionary Learning

Denis Makhov, Dmitriy Shopkhoev, Magauiya Zhussip +2

Post-training LLM compression often relies on low-rank approximations, which force all columns of a projection matrix to share a single low-dimensional subspace. We propose CoSpaDi…

cs.CL2025

Share Your Attention: Transformer Weight Sharing via Matrix-based Dictionary Learning

Magauiya Zhussip, Dmitriy Shopkhoev, Ammar Ali +1

Large language models have revolutionized AI applications, yet their high computational and memory demands hinder their widespread deployment. Existing compression techniques focus…

cs.CL2025

ReplaceMe: Network Simplification via Depth Pruning and Transformer Block Linearization

Dmitriy Shopkhoev, Ammar Ali, Magauiya Zhussip +4

We introduce ReplaceMe, a generalized training-free depth pruning method that effectively replaces transformer blocks with a linear operation, while maintaining high performance fo…

cs.CV2024

Robust Two-View Geometry Estimation with Implicit Differentiation

Vladislav Pyatov, Iaroslav Koshelev, Stamatis Lefkimmiatis

We present a novel two-view geometry estimation framework which is based on a differentiable robust loss function fitting. We propose to treat the robust fundamental matrix estimat…

cs.RO2024

GSLoc: Visual Localization with 3D Gaussian Splatting

Kazii Botashev, Vladislav Pyatov, Gonzalo Ferrer +1

We present GSLoc: a new visual localization method that performs dense camera alignment using 3D Gaussian Splatting as a map representation of the scene. GSLoc backpropagates pose…

cs.CV2023

NeuSD: Surface Completion with Multi-View Text-to-Image Diffusion

Savva Ignatyev, Daniil Selikhanovych, Oleg Voynov +4

We present a novel method for 3D surface reconstruction from multiple images where only a part of the object of interest is captured. Our approach builds on two recent developments…

cs.CV2023★ 2 cited

Iterative Reweighted Least Squares Networks With Convergence Guarantees for Solving Inverse Imaging Problems

Iaroslav Koshelev, Stamatios Lefkimmiatis

In this work we present a novel optimization strategy for image reconstruction tasks under analysis-based image regularization, which promotes sparse and/or low-rank solutions in s…

cs.CV2023★ 3 cited

Learning Sparse and Low-Rank Priors for Image Recovery via Iterative Reweighted Least Squares Minimization

Stamatios Lefkimmiatis, Iaroslav Koshelev

We introduce a novel optimization algorithm for image recovery under learned sparse and low-rank constraints, which we parameterize as weighted extensions of the -vector…

eess.IV2021

DeepRLS: A Recurrent Network Architecture with Least Squares Implicit Layers for Non-blind Image Deconvolution

Iaroslav Koshelev, Daniil Selikhanovych, Stamatios Lefkimmiatis

In this work, we study the problem of non-blind image deconvolution and propose a novel recurrent network architecture that leads to very competitive restoration results of high im…

eess.IV2020

Maxwell Parallel Imaging

Matteo Alessandro Francavilla, Stamatios Lefkimmiatis, Jorge F. Villena +1

Purpose: To develop a general framework for Parallel Imaging (PI) with the use of Maxwell regularization for the estimation of the sensitivity maps (SMs) and constrained optimizati…

eess.IV2019

Microscopy Image Restoration with Deep Wiener-Kolmogorov filters

Valeriya Pronina, Filippos Kokkinos, Dmitry V. Dylov +1

Microscopy is a powerful visualization tool in biology, enabling the study of cells, tissues, and the fundamental biological processes; yet, the observed images typically suffer fr…

cs.CV2018

Iterative Residual CNNs for Burst Photography Applications

Filippos Kokkinos, Stamatios Lefkimmiatis

Modern inexpensive imaging sensors suffer from inherent hardware constraints which often result in captured images of poor quality. Among the most common ways to deal with such lim…

cs.CV2018★ 117 cited

Iterative Joint Image Demosaicking and Denoising using a Residual Denoising Network

Filippos Kokkinos, Stamatios Lefkimmiatis

Modern digital cameras rely on the sequential execution of separate image processing steps to produce realistic images. The first two steps are usually related to denoising and dem…

cs.CV2018

Deep Image Demosaicking using a Cascade of Convolutional Residual Denoising Networks

Filippos Kokkinos, Stamatios Lefkimmiatis

Demosaicking and denoising are among the most crucial steps of modern digital camera pipelines and their joint treatment is a highly ill-posed inverse problem where at-least two-th…

cs.CV2017

Universal Denoising Networks : A Novel CNN Architecture for Image Denoising

Stamatios Lefkimmiatis

We design a novel network architecture for learning discriminative image models that are employed to efficiently tackle the problem of grayscale and color image denoising. Based on…

cs.CV2016

Non-Local Color Image Denoising with Convolutional Neural Networks

Stamatios Lefkimmiatis

We propose a novel deep network architecture for grayscale and color image denoising that is based on a non-local image model. Our motivation for the overall design of the proposed…

math.OC2012★ 174 cited

Hessian Schatten-Norm Regularization for Linear Inverse Problems

Stamatios Lefkimmiatis, John Paul Ward, Michael Unser

We introduce a novel family of invariant, convex, and non-quadratic functionals that we employ to derive regularized solutions of ill-posed linear inverse imaging problems. The pro…