pletion of this thesis. Their invaluable support, guidance, and encouragement have been indispensable during the entirety of my research journey. This thesis is a testament to their collective efforts and support. First and foremost, I wish to express my deepest gratitude to my supervisor Prof. Shijian Lu, for his continuous guidance, patience, and invaluable advice. His insightful feedback and dedication to my academic and personal growth have played a crucial role in shaping this research project. Without his patient guidance and thoughtful counsel, I would not have been able to accomplish my research and successfully conclude my studies. I also want to express my profound gratitude to my collaborators, especially Dr. Fangneng Zhan, for their insightful input, helpful advice, and unwavering support during my research endeavors. Furthermore, I extend my gratitude to all members of Prof. Lu's team, my friends in the Alibaba Talent Programme and Media and Interactive Computing Lab (MICL), for their generous assistance and encouragement, which have made my academic journey and time spent in Singapore truly memorable. I would like to express my gratitude to my fellow members of the Vision Intelligent Team at DAMO Academy, Alibaba, specifically my team leaders, Ms. Feiyang Ma and Ms. Miaomiao Cui, for supporting me with computational resources, technical assistance, and insightful suggestions. My heartfelt thanks go to the School of Computer Science and Engineering, Nanyang Technological University (NTU), for providing me with the necessary resources and a conducive environment for my research. I also would like to acknowledge Alibaba-NTU Singapore Joint Research Institute for offering me this Industrial Post-Graduate Program and for their support during my studies. xi xii Special thanks to my former colleague, Dr. Pan Liu, for his continuous support and invaluable assistance throughout the process of my Ph.D. application. Last but not the least, I am forever grateful to my parents, for their unconditional love, constant encouragement, and unwavering belief in my capabilities throughout my life. Their support and understanding have been the bedrock of my academic pursuits.