SNSaqib Nazir

Saqib Nazir

*This is an algorithmically generated author record based on publicly available information.

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:


Latest Publications

  • Open Access

    Context-Aware Graph Neural Network for Skin Lesion Classification

    by Muhammad Azeem, Saqib Nazir, Amr Ahmed, Ardhendu Behera


  • Open Access

    Federated Reinforcement Learning with Hybrid Optimization for Secure and Reliable Data Transmission in Wireless Sensor Networks (WSNs)

    by Seyed Salar Sefati, Seyedeh Tina Sefati, Saqib Nazir, Roya Zareh Farkhady, Serban Georgica Obreja

    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

    by Saqib Nazir, Olivier Lézoray, Sébastien Bougleux

    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 Access

    Depth Estimation and Image Restoration by Deep Learning From Defocused Images

    by Saqib Nazir, Lorenzo Vaquero, Manuel Mucientes, Víctor M. Brea, Daniela Coltuc

    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.


  • iDFD: A Dataset Annotated for Depth and Defocus

    by Saqib Nazir, Zhouyan Qiu, Daniela Coltuc, Joaquín Martínez-Sánchez, Pedro Arias


  • Open Access

    Edge-preserving Smoothing Regularization for Monocular Depth Estimation

    by Saqib Nazir, Daniela Coltuc

    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.