This book constitutes the thoroughly refereed post-workshop-proceedings of the 4th International Workshop on Camera-Based Document Analysis and Recognition, CBDAR 2011, held in Beijing, China, in September 2011. The 13 revised full papers presented were carefully selected during a second round of reviewing and improvement from numerous original submissions. Intended to give a snapshot of the state-of-the-art research in the field of camera based document analysis and recognition, the papers are organized in topical sections on text detection and recognition in scene images, camera-based systems, and datasets and evaluation.