Review of Related Work

• Multimedia Document Systems
• Multimedia Extensions to Existing Database Systems
• Two driving forces for time-based media aware database systems:
  • New multimedia applications that would benefit from or require access to large databases of time-based media, such as video-on-demand.
  • Large repositories of "clip media" or "digital assets" are loosely organized collections of files.
• Temporal Databases
  • Time sequences describe the attributes or values of objects over the life of the object.
• Video Authoring Tools
  • Time-line metaphor
  • Media objects are aggregations of smaller units (media elements)
• Algebraic Video Model
  • Describes composition of media objects in temporal and spatial regards
  • Makes use of video expressions made up of video algebra operations
• Layered Multimedia Data Model (LMDM)
  • Used in some recent prototypes of multimedia database systems
  • Event calculus to define complex operations in terms of simpler ones
  • Temporal and spatial structures and control of synchronization
• Real-Time Database Systems
  • Hard deadlines are not used.