Despite recent advances in authoring systems and tools, creating multimedia presentations remains a labor-intensive process. This paper describes a system for automatically constructing structured multimedia documents from live presentations. The automatically produced documents contain synchronized and edited audio, video, images, and text. Two essential problems, synchronization of captured data and automatic editing, are identified and solved.

This paper presents a new approach for constructing libraries for building processing-intensive multimedia software. Such software is currently constructed either "from scratch" or by using high-level libraries. We have found that the second approach produces inefficient code, while the first approach is time-consuming. We therefore designed and implemented Dali, a set of reusable, high-performance primitives and abstractions that are at an intermediate point in this design space. By decomposing common multimedia data types and operations into thin abstractions and primitives, programs written using Ball are shorter and more reusable than hand-tuned C code, yet achieve competitive performance. This paper describes the design and implementation of Dali.