Far Field Video

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Far Field Video

• Andy Wilson
• COMP290-72 Final Presentation

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Motivation

• Accelerate massive model rendering by
  representing distant geometry with simple
  impostor
• Use MPEG encoding to take advantage of coherence
  between impostors for adjacent cells

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State of the Art

• Massive model rendering the Walkthrough MMR
  system
• Video representation numerous techniques
  (MPEG1-3, Intel Indeo, H.263, etc.)
• Far-field representations image-based impostors
  (TDM, LDI, QTVR, etc.)

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Goals

• Automatically find paths through a model
• Generate video stream from those paths
• Allow bidirectional motion through image stream
• Integrate video into viewer

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Major Setbacks

• Freely available video codecs (with source) are
  difficult to adapt
• Bidirectional stream navigation requires a lot of
  work
• Inter-frame dependencies make random access
  difficult
• Many cryptic parameters in encoder have large
  effect on quality of output

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Sample Loss of Quality
MPEG
Normal (PNG)
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Future Work

• Better paths through model
• more coherence means better images, smaller
  streams
• Problem known to be NP-complete!
• Bidirectional navigation
• Probably requires complete rewrite of MPEG
  decoder
• Other representations
• panorama, cell-wall movie, ?

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Demo MMR with video images