Quantum machine learning for object detection and segmentation: A comprehensive survey and future research directions

Small objects have become increasingly common in civil, industrial, and security sensitive environments, driving a strong demand for reliable vision-based detection and segmentation. While deep learning (DL) models have achieved impressive performance, their practicality is limited by the small sizes of objects, cluttered backgrounds, motion blur, domain shift, and the growing cost of training and inference. Quantum machine learning (QML) has recently emerged as a potential research direction for exploring alternative feature representations, optimization strategies, and learning paradigms under resource constrained conditions. However, its practical efficiency benefits for object detection and segmentation remain largely preliminary and context dependent. The literature on quantum methods for detection and segmentation is scattered across the QML, aerial vision, and remote sensing domains. We provide a structured review of quantum, hybrid quantum–classical (HQC), and quantum approaches for detection and segmentation. We classify existing methods based on four aspects: how features are encoded and represented in quantum systems, the use of quantum kernels, variational quantum circuits (VQC) for classification and detection, and quantum architectures combined with modern detection and segmentation models. We summarize the commonly used datasets for quantum techniques, evaluation protocols, and computational constraints, comparing the reported performance trends, scalability levels, and practical limitations of quantum-based methods. Finally, we identify the open challenges, including data-efficient learning, robustness to domain shift, and end-to-end quantum segmentation, along with the research directions relevant to bridging the gap between QML and real-world object perception systems.