Book excerpt: This book includes high-quality research papers presented at the Fourth International Conference on Image Processing and Capsule Networks (ICIPCN 2023), which is held in Bangkok, Thailand, during 10–11 August 2023. This book provides a collection of the state-of-the-art research attempts to tackle the challenges in image and signal processing from various novel and potential research perspectives. The book investigates feature extraction techniques, image enhancement methods, reconstruction models, object detection methods, recommendation models, deep and temporal feature analysis, intelligent decision support systems, and autonomous image detection models. In addition to this, the book also looks into the potential opportunities to monitor and control the global pandemic situations.