Camera-Based System for User Friendly Annotation of Documents

We propose a system for document annotation using a camera mounted on a smartphone. It works both on paper documents and electronic documents thanks to the functionality of document image retrieval. An important characteristic of this system is in the way of annotating documents. The system employs simple character stickers which represent user's opinions ("hard to understand", "interesting", "boring", "surprising", "doubtful") for friendly annotation on documents. We evaluated our system by changing the way of annotation and found that users most liked the proposed way of annotation with stickers though it sometimes caused a confusion about the interpretation of stickers. We discuss the possible way of solving this issue as a result of the analysis of experimental results.