His research interests include computer vision and deep learning with a focus on image/video restoration and enhancement, generative tasks, and representation learning. He has published more than 140 papers in top journals and conferences of computer vision and machine learning. He and his research group pioneer the research in face detection, face alignment, and image super-resolution by deep learning. His journal paper on image super-resolution was selected as the `Most Popular Article' by IEEE Transactions on Pattern Analysis and Machine Intelligence in 2016. It remains as one of the top 10 articles to date.