A Collaborative Interface for Multimodal Ink and Audio Documents

With the increased availability of pen-based devices, it becomes interesting to conduct and to archive multi-party communication sessions that involve audio and digital ink on a shared canvas. Collaborative whiteboards do exist today but typically use complex or closed protocols for communication. As a rule, existing whiteboards are not interoperable across multiple platforms and do not support archival of collaborative sessions for later reference or analysis. We explore how various data formats may be used to represent, to transmit, to record and to synchronize ink and audio channels. We find InkML to be a suitable representation to support platform-independent digital ink in a form supporting both transmission and higher-level semantic analysis. To test our ideas we have developed a complete software implementation as a Skype add-on. This has revealed possible improvements to the page and streaming models of InkML.