Embedding metadata in computer graphics for interaction

Digital images or 3D visualizations often need to be augmented with information that assists the viewer in understanding what is portrayed or that provides additional knowledge. The data representation of such descriptive metadata is a challenging task since digital media can be stored in various forms each of which provides, if at all, its own specific method for integrating its assigned metadata. The author analyzes existing techniques and introduces new approaches to store a digital medium, for example a digital image, and additional information associated with that medium, for example texts, other images, or auditory data. Illustration Watermarking as a subclass of information hiding emerged as an applicable technique in this regard. Besides the internal representation of descriptive metadata, its visual representation is another aspect addressed in this work. Taking into consideration that display space is limited, techniques for guiding the viewer to those regions associated with the metadata sought and techniques for presenting the metadata are introduced. Many interesting application scenarios illustrate what is envisioned by the author.