Real-time collaborative annotation system supporting separation of content and annotation

Abstract

In earlier collaborative annotation system, the details of all comments were presented in the form of images and were marked directly on the contents. This approach may cause visual confusion no matter what style people choose to display annotations by overlaying contents or by overlapping other comments. This article introduces a new annotation display model to separate contents and annotations, and the MPSAC (Multi-processing and Separation of Annotation and Content) strategy was presented to achieve the consistency maintenance of different collaborative sites based on this model. With the foundation of controlling executive operations’ effect and maintaining the consistency of annotations, the strategy discovers and resolves the collision problem among overlapped annotations and provide a better interactive experience for users. The feasibility and correctness of this strategy were verified by case analysis and CoNote model system at the end of this paper.