An automatic framework for endoscopic image restoration and enhancement

Abstract

Despite its success in the field of minimally invasive surgery, endoscopy image analysis remains challenging due to limited image settings and control conditions. The low resolution and existence of large number of reflections in endoscopy images are the major problems in the automatic detection of objects. To address these issues, we presented a novel framework based on the convolutional neural networks. The proposed approach consists of three major parts. First, a deep learning (DL)-based image evaluation method is used to classify the input images into two groups, namely, specular highlights and weakly illuminated groups. Second, the specular highlight is detected using the DL-based method, and the reflected areas are recovered through a patch-based restoration operation. Lastly, gamma correction with optimized reflectance and illumination estimation is adopted to enhance the weakly illuminated images. The proposed method is compared against the existing ones, and the experimental results demonstrate that the former outperforms the latter in terms of subjective and objective assessments. This finding indicates that the proposed approach can serve as a potential tool for improving the quality of the endoscopy images used to examine internal body organs.