This book constitutes the refereed proceedings of the 21st International Workshop, IWDW 2022, held in Guilin, China, during November 18-19, 2022. The 14 full papers included in this book were carefully reviewed and selected from 30 submissions. They were organized in topical sections as follows: Steganology, Forensics and Security Analysis, Watermarking.

This volume constitutes the proceedings of the 20th International Workshop on Digital Forensics and Watermarking, IWDW 2021, held in Beijing, China, in November 2021. The 18 full papers in this volume were carefully reviewed and selected from 32 submissions. The are categorized in the following topical headings: Forensics and Security Analysis; Watermarking and Steganology.