SDMFFN: a novel specular detection median filtering fusion network for specular reflection removal in endoscopic images

<i>Objective</i>. Endoscopic imaging is vital in Minimally Invasive Surgery (MIS), but its utility is often compromised by specular reflections that obscure important details and hinder diagnostic accuracy. Existing methods to address these reflections face limitations, particularly those relying on color-based thresholding and the underutilization of deep learning for highlight detection.<i>Approach</i>. To tackle these challenges, we propose the Specular Detection Median Filtering Fusion Network (SDMFFN), a novel framework designed to detect and remove specular reflections in endoscopic images. The SDMFFN employs a two-stage process: detection and removal. In the detection phase, we utilize the enhanced Specular Transformer Unet (S-TransUnet) model integrating Atrous Spatial Pyramid Pooling (ASPP), Information Bottleneck (IB) and Convolutional Block Attention Module (CBAM) to optimize multi-scale feature extraction, which helps to achieve accurate highlight detection. In the removal phase, we improve the advanced median filtering to smooth reflective areas and integrate color information for a natural restoration.<i>Main results</i>. Experimental results show that our proposed SDMFFN has outperformed other methods. Our method improves visual clarity and diagnostic precision, ultimately enhancing surgical outcomes and reducing the risk of misdiagnosis by delivering high-quality, reflection-free endoscopic images.<i>Significance</i>. The robust performance of SDMFFN suggests its adaptability to other medical imaging modalities, paving the way for broader clinical and research applications in robotic surgery, diagnostic endoscopy and telemedicine. To promote further progress in the research, we will make the code publicly available at:https://github.com/jize123457/SDMFFN.