This book presents selected papers from the 19th International Conference on Intelligent Information Hiding and Multimedia Signal Processing, in conjunction with the 11th International Conference on Orange Technology, Applications, and Tools, held on December 5-7, 2023, in Daegu, South Korea. It is divided into two volumes and discusses latest research outcomes in the field of information technology (IT) including but not limited to information hiding, multimedia signal processing, big data, data mining, bioinformatics, database, industrial and internet of things, and their applications.