Saqib Nazir
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Saqib Nazir has a total of 18 co-authors. Here are the top co-authors by number of shared publications:
- Daniela Coltuc
Politehnica Univ. of Bucharest (Romania)
3 shared publications - Olivier Lézoray
Université Caen Normandie, ENSICAEN, CNRS, Normandie Univ., GREYC UMR 6072
3 shared publications - Sébastien Bougleux
Université Caen Normandie, ENSICAEN, CNRS, Normandie Univ, GREYC UMR 6072, F-14000 Caen, France
2 shared publications - Amr Ahmed
Edge Hill University
1 shared publication - Ardhendu Behera
Edge Hill University
1 shared publication - Ardhendu Behera
Edge Hill University
1 shared publication
Latest Publications
- 3 August 2026
- Published by Springer Nature
- p. 629-644
Towards Label-Free Single-Cell Phenotyping Using Multi-task Learning
- 3 August 2026
- Published by Springer Nature
- p. 629-644
Towards Label-Free Single-Cell Phenotyping Using Multi-task Learning
- Open Access
- 23 March 2026
- Published by Association for Computing Machinery (ACM)
- p. 164-173
Context-Aware Graph Neural Network for Skin Lesion Classification
- 23 March 2026
- Published by Association for Computing Machinery (ACM)
- p. 164-173
Open AccessContext-Aware Graph Neural Network for Skin Lesion Classification
- Open Access
- 9 January 2026
- Published by Elsevier in Neurocomputing
- Vol. 671
3DGeoMeshNet: A multi-scale graph auto-encoder for 3D mesh reconstruction and completion
- 9 January 2026
- Published by Elsevier in Neurocomputing
- Vol. 671
Open Access3DGeoMeshNet: A multi-scale graph auto-encoder for 3D mesh reconstruction and completion
- Open Access
- 6 October 2025
- Published by MDPI AG in Mathematics
- Vol. 13 (19) , 3196
Federated Reinforcement Learning with Hybrid Optimization for Secure and Reliable Data Transmission in Wireless Sensor Networks (WSNs)
Wireless Sensor Networks (WSNs) consist of numerous battery-powered sensor nodes that operate with limited energy, computation, and communication capabilities. Designing routing strategies that are both energy-efficient and attack-resilient is essential for extending network lifetime and ensuring secure data delivery. This paper proposes Adaptive Federated Reinforcement Learning-Hunger Games Search (AFRL-HGS), a Hybrid Routing framework that integrates multiple advanced techniques. At the node level, tabular Q-learning enables each sensor node to act as a reinforcement learning agent, making next-hop decisions based on discretized state features such as residual energy, distance to sink, congestion, path quality, and security. At the network level, Federated Reinforcement Learning (FRL) allows the sink node to aggregate local Q-tables using adaptive, energy- and performance-weighted contributions, with Polyak-based blending to preserve stability. The binary Hunger Games Search (HGS) metaheuristic initializes Cluster Head (CH) selection and routing, providing a well-structured topology that accelerates convergence. Security is enforced as a constraint through a lightweight trust and anomaly detection module, which fuses reliability estimates with residual-based anomaly detection using Exponentially Weighted Moving Average (EWMA) on Round-Trip Time (RTT) and loss metrics. The framework further incorporates energy-accounted control plane operations with dual-format HELLO and hierarchical ADVERTISE/Service-ADVERTISE (SrvADVERTISE) messages to maintain the routing tables. Evaluation is performed in a hybrid testbed using the Graphical Network Simulator-3 (GNS3) for large-scale simulation and Kali Linux for live adversarial traffic injection, ensuring both reproducibility and realism. The proposed AFRL-HGS framework offers a scalable, secure, and energy-efficient routing solution for next-generation WSN deployments.
- 6 October 2025
- Published by MDPI AG in Mathematics
- Vol. 13 (19) , 3196
Open AccessFederated Reinforcement Learning with Hybrid Optimization for Secure and Reliable Data Transmission in Wireless Sensor Networks (WSNs)
Wireless Sensor Networks (WSNs) consist of numerous battery-powered sensor nodes that operate with limited energy, computation, and communication capabilities. Designing routing strategies that are both energy-efficient and attack-resilient is essential for extending network lifetime and ensuring secure data delivery. This paper proposes Adaptive Federated Reinforcement Learning-Hunger Games Search (AFRL-HGS), a Hybrid Routing framework that integrates multiple advanced techniques. At the node level, tabular Q-learning enables each sensor node to act as a reinforcement learning agent, making next-hop decisions based on discretized state features such as residual energy, distance to sink, congestion, path quality, and security. At the network level, Federated Reinforcement Learning (FRL) allows the sink node to aggregate local Q-tables using adaptive, energy- and performance-weighted contributions, with Polyak-based blending to preserve stability. The binary Hunger Games Search (HGS) metaheuristic initializes Cluster Head (CH) selection and routing, providing a well-structured topology that accelerates convergence. Security is enforced as a constraint through a lightweight trust and anomaly detection module, which fuses reliability estimates with residual-based anomaly detection using Exponentially Weighted Moving Average (EWMA) on Round-Trip Time (RTT) and loss metrics. The framework further incorporates energy-accounted control plane operations with dual-format HELLO and hierarchical ADVERTISE/Service-ADVERTISE (SrvADVERTISE) messages to maintain the routing tables. Evaluation is performed in a hybrid testbed using the Graphical Network Simulator-3 (GNS3) for large-scale simulation and Kali Linux for live adversarial traffic injection, ensuring both reproducibility and realism. The proposed AFRL-HGS framework offers a scalable, secure, and energy-efficient routing solution for next-generation WSN deployments.
- Open Access
Self-Attention Based Multi-Scale Graph Auto-Encoder Network of 3D Meshes
3D meshes are fundamental data representations for capturing complex geometric shapes in computer vision and graphics applications. While Convolutional Neural Networks (CNNs) have excelled in structured data like images, extending them to irregular 3D meshes is challenging due to the non-Euclidean nature of the data. Graph Convolutional Networks (GCNs) offer a solution by applying convolutions to graph-structured data, but many existing methods rely on isotropic filters or spectral decomposition, limiting their ability to capture both local and global mesh features. In this paper, we introduce 3D Geometric Mesh Network (3DGeoMeshNet), a novel GCN-based framework that uses anisotropic convolution layers to effectively learn both global and local features directly in the spatial domain. Unlike previous approaches that convert meshes into intermediate representations like voxel grids or point clouds, our method preserves the original polygonal mesh format throughout the reconstruction process, enabling more accurate shape reconstruction. Our architecture features a multi-scale encoder-decoder structure, where separate global and local pathways capture both large-scale geometric structures and fine-grained local details. Extensive experiments on the COMA dataset containing human faces demonstrate the efficiency of 3DGeoMeshNet in terms of reconstruction accuracy.
Open AccessSelf-Attention Based Multi-Scale Graph Auto-Encoder Network of 3D Meshes
3D meshes are fundamental data representations for capturing complex geometric shapes in computer vision and graphics applications. While Convolutional Neural Networks (CNNs) have excelled in structured data like images, extending them to irregular 3D meshes is challenging due to the non-Euclidean nature of the data. Graph Convolutional Networks (GCNs) offer a solution by applying convolutions to graph-structured data, but many existing methods rely on isotropic filters or spectral decomposition, limiting their ability to capture both local and global mesh features. In this paper, we introduce 3D Geometric Mesh Network (3DGeoMeshNet), a novel GCN-based framework that uses anisotropic convolution layers to effectively learn both global and local features directly in the spatial domain. Unlike previous approaches that convert meshes into intermediate representations like voxel grids or point clouds, our method preserves the original polygonal mesh format throughout the reconstruction process, enabling more accurate shape reconstruction. Our architecture features a multi-scale encoder-decoder structure, where separate global and local pathways capture both large-scale geometric structures and fine-grained local details. Extensive experiments on the COMA dataset containing human faces demonstrate the efficiency of 3DGeoMeshNet in terms of reconstruction accuracy.
- 1 April 2025
- Published by Springer Nature
- p. 69-80
Joint Underwater Depth Estimation and Dehazing from a Single Image Using Attention U-Net
- 1 April 2025
- Published by Springer Nature
- p. 69-80
Joint Underwater Depth Estimation and Dehazing from a Single Image Using Attention U-Net
- Open Access
- 21 June 2023
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Transactions on Computational Imaging
- Vol. 9 (25730436) , 607-619
Depth Estimation and Image Restoration by Deep Learning From Defocused Images
Monocular depth estimation and image deblurring are two fundamental tasks in computer vision, given their crucial role in understanding 3D scenes. Performing any of them by relying on a single image is an ill-posed problem. The recent advances in the field of Deep Convolutional Neural Networks (DNNs) have revolutionized many tasks in computer vision, including depth estimation and image deblurring. When it comes to using defocused images, the depth estimation and the recovery of the All-in-Focus (Aif) image become related problems due to defocus physics. Despite this, most of the existing models treat them separately. There are, however, recent models that solve these problems simultaneously by concatenating two networks in a sequence to first estimate the depth or defocus map and then reconstruct the focused image based on it. We propose a DNN that solves the depth estimation and image deblurring in parallel. Our Two-headed Depth Estimation and Deblurring Network (2HDED:NET) extends a conventional Depth from Defocus (DFD) networks with a deblurring branch that shares the same encoder as the depth branch. The proposed method has been successfully tested on two benchmarks, one for indoor and the other for outdoor scenes: NYU-v2 and Make3D. Extensive experiments with 2HDED:NET on these benchmarks have demonstrated superior or close performances to those of the state-of-the-art models for depth estimation and image deblurring.
- 21 June 2023
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Transactions on Computational Imaging
- Vol. 9 (25730436) , 607-619
Open AccessDepth Estimation and Image Restoration by Deep Learning From Defocused Images
Monocular depth estimation and image deblurring are two fundamental tasks in computer vision, given their crucial role in understanding 3D scenes. Performing any of them by relying on a single image is an ill-posed problem. The recent advances in the field of Deep Convolutional Neural Networks (DNNs) have revolutionized many tasks in computer vision, including depth estimation and image deblurring. When it comes to using defocused images, the depth estimation and the recovery of the All-in-Focus (Aif) image become related problems due to defocus physics. Despite this, most of the existing models treat them separately. There are, however, recent models that solve these problems simultaneously by concatenating two networks in a sequence to first estimate the depth or defocus map and then reconstruct the focused image based on it. We propose a DNN that solves the depth estimation and image deblurring in parallel. Our Two-headed Depth Estimation and Deblurring Network (2HDED:NET) extends a conventional Depth from Defocus (DFD) networks with a deblurring branch that shares the same encoder as the depth branch. The proposed method has been successfully tested on two benchmarks, one for indoor and the other for outdoor scenes: NYU-v2 and Make3D. Extensive experiments with 2HDED:NET on these benchmarks have demonstrated superior or close performances to those of the state-of-the-art models for depth estimation and image deblurring.
- Open Access
- 2 September 2021
- Published by Institute of Electrical and Electronics Engineers (IEEE)
Edge-preserving Smoothing Regularization for Monocular Depth Estimation
Monocular depth estimation is a fundamental challenge since the foundation of computer vision with many real-world applications. Recently, the introduction of Deep Convolutional Neural Networks (CNN) has brought significant improvements to this particular problem. There are many solutions for scene depth estimation with a focus on obtaining high-quality depth maps from a given RGB image. The insertion of prior information by adding a smoothing regularization has improved the results. However, the smoothing of the surfaces comes together with a certain degradation of the edges. The goal of this paper is to make a comparison between various regularization terms used either in supervised or self-supervised learning methods. In addition to this, we modified the regularization term used currently in self-supervised methods such to work in a supervised manner. The experimental results on NYU-Depth v2 have shown that the regularization based on L1 norm of the gradient is the best and the self-supervised modified one outperforms the rest. Finally, rather than relying on common evaluation metrics, we used an additional accuracy measure based on the Steerable Pyramid and Kullback-Leibler divergence (KLD) for edge accuracy of estimated depths that is more sensitive to positional errors of the edges.
- 2 September 2021
- Published by Institute of Electrical and Electronics Engineers (IEEE)
Open AccessEdge-preserving Smoothing Regularization for Monocular Depth Estimation
Monocular depth estimation is a fundamental challenge since the foundation of computer vision with many real-world applications. Recently, the introduction of Deep Convolutional Neural Networks (CNN) has brought significant improvements to this particular problem. There are many solutions for scene depth estimation with a focus on obtaining high-quality depth maps from a given RGB image. The insertion of prior information by adding a smoothing regularization has improved the results. However, the smoothing of the surfaces comes together with a certain degradation of the edges. The goal of this paper is to make a comparison between various regularization terms used either in supervised or self-supervised learning methods. In addition to this, we modified the regularization term used currently in self-supervised methods such to work in a supervised manner. The experimental results on NYU-Depth v2 have shown that the regularization based on L1 norm of the gradient is the best and the self-supervised modified one outperforms the rest. Finally, rather than relying on common evaluation metrics, we used an additional accuracy measure based on the Steerable Pyramid and Kullback-Leibler divergence (KLD) for edge accuracy of estimated depths that is more sensitive to positional errors of the edges.