Lecture Webcasting and Distributed Collaboration

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Lecture Webcasting and Distributed Collaboration
Research Summary January 2001

• Lawrence A. Rowe
• Computer Science Division - EECS
• University of California at Berkeley
• Rowe_at_BMRC.Berkeley.EDU

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Outline

• Berkeley Internet Broadcasting System (BIBS)
• Live/on-demand class lectures
• Program guide and automated operations
• (see http//bmrc.berkeley.edu/bibs)
• Berkeley Lecture Browser
• Multiple streams
• Browsing, slide indexes, searching, etc.
• (see http//bmrc.berkeley.edu/projects/lb)
• Research Issues
• Educational effectiveness
• Improved quality
• BIBS operational infrastructure

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BIBS Lecture Webcasting

• Webcast class lectures
• Live webcasts for remote viewing
• On-demand replay for review and watching missed
  lectures
• Fall 1998 and spring 1999 small experiments
• Approximately 5 classes with one hundred students
• Scaled up in fall 1999 continues today
• Webcasting 14 classes with enrollment of 3,000
• Using Real Networks SureStream (50/200 Kbs)
• Adding functionality to Real Webcasts
• 2-stream programs (speaker content)
• Lecture browser (video synchronized slides )

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BIBS Program Guide
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Sample Lectures
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Dual-Stream Webcast
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Berkeley Lecture Browser

• Multiple streams
• Speaker presentation material (e.g., slides,
  images, video, live demo, etc.)
• Operations
• Browse presentation material while watching
• Random positioning, search indexes, fast replay,
  etc.
• Links to related material including student notes
• Low cost authoring!
• Automatic capture of slide timings work remains
  here
• Experimented with speech2text translation not
  yet!

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Lecture Browser
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BIBS RD Issues

• Educational effectiveness?
• Improved quality
• Multiple streams with user control
• Remote and local interaction requires sense of
  presence
• Improved audio and visual material
• Augment content user notes, improved
  outline/summarization, etc.
• BIBS operational infrastructure
• Authenticated access controls pay-per-view?
• Support for disabled (e.g., closed captioning)
• Experiment with new room facilities
• Automate operations and improve reliability

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Room Design Issues

• Cost/performance
• Low cost webcast source (15K-25K)
• Medium cost colab (50K)
• High cost broadcast facility (100K-500K)
• Maintenance and operational costs important too!
• Must adapt to instructor style
• Multiple presentation projectors accept variety
  of presentation material
• Ad hoc presentation tools with saved material
• Seamless user interface
• Turn on lights and start lecture
• Put this window there

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Webcasting Architecture
colab
studio

• N-way communication
• Multiple streams and discussion threads
• User control of content (e.g., select streams)
• Variable bit rates streams

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Webcast Production

• Standard tools
• Real Networks and Internet Mbone
• Broadcast Manager for launching webcasts
• Directors Console for live production control
• Question Board for floor control and remote
  questions
• Software-only Video Effects System improves
  visual quality

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Directors Console

• Lists available sources
• Shows current stream(s)
• Controls to manipulate stream (e.g., move camera
  or position stored media)
• Extensible interface to support new sources and
  controls
• Eventual goal is to automate this process

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Research Problems

• Automation and control of webcasts
• Develop heuristics to automatically control
  broadcasts
• Bandwidth adaptation based on heuristics and use
• Compilation and planning of video effects
• Given high-level effect description and machine
  resource description, produce plan to execute
  effect within required performance constraints
• Dynamic optimization of effects processing across
  many users
• User-interface for presenter
• Sense of presence for remote participants
• Improved interface for ad hoc presentations
  (e.g., tablet, display control, etc.)
• Lecture capture and browsing
• Capture more than just slides and video (e.g.,
  notes, links to related material, search indexes,
  etc.)

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Automated Control

• Speaker switches source
• implies content stream should be switched
• Audience question sensed on mics
• implies change content to audience cam modify
  audio levels
• Script for webcast
• openning, speakercontent, speaker titling at
  f(curtime), periodic switch from wide shot to
  speaker closeup
• Speaker/moderator recognizes remote question
• switch content and local projection to remote
  speaker
• Speaker talks to room/webcast control system
• Please show the whiteboard.
• etc.

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References

• Broadcast Manager
• An Internet MBone Broadcast Management System by
  D. Wu, A. Swan, and L.A. Rowe, SPIE Multimedia
  Computing and Networking, January
  1999.http//bmrc.berkeley.edu/research/publicatio
  ns/1999/151/
• Directors Console
• dc A Live Webcast Control System by T.P. Yu, D.
  Wu, K. Meyer-Patel, and L.A. Rowe, submitted for
  publication, January 2000. http//bmrc.berkeley.e
  du/research/publications/2000/157/
• QuestionBoard
• Floor Control for Large-Scale MBone Seminarsby
  R. Malpani and L.A. Rowe.Proc. of The Fifth
  Annual ACM Intl. Multimedia Conf., November
  1997.http//bmrc.berkeley.edu/research/publicatio
  ns/1997/137/
• Parallel Video Special Effects
• Exploiting Temporal Parallelism For Software-only
  Video Effects Processing by Ketan Mayer-Patel
  and L.A. Rowe. Proc. of The Sixth Annual ACM
  Intl. Multimedia Conf., September
  1998http//www.bmrc.berkeley.edu/research/publica
  tions/1998/149/149.html.

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References (cont.)

• Parallel Video Special Effects (cont.)
• Exploiting Temporal Parallelism For Software-only
  Video Effects Processing by Ketan Mayer-Patel
  and L.A. Rowe. Proc. of The Sixth Annual ACM
  Intl. Multimedia Conf., September
  1998http//bmrc.berkeley.edu/research/publication
  s/1998/149/149.html.
• Exploiting Spatial Parallelism For Software-only
  Video Effects Processing by K. Mayer-Patel and
  L.A. Rowe,SPIE Multimedia Computing and
  Networking, January 1999. http//bmrc.berkeley.e
  du/research/publications/1999/150/
• Multicast Control Scheme For Parallel
  Software-only Video Effects Processingby K.
  Mayer-Patel and L.A. Rowe.Proc. of The Seventh
  Annual ACM Intl. Multimedia Conf., October
  1999.http//bmrc.berkeley.edu/research/publicatio
  ns/1999/154/
• A Parallel Software-Only Video Effects Processing
  Systemby K. Mayer-Patel.PhD Dissertation,
  Computer Science, U.C. Berkeley, December
  1999.http//www.bmrc.berkeley.edu/research/public
  ations/1999/155/index.html
• Layered Source/Channel Transmission
• Layered Transmission and Caching for the
  Multicast Session Directory Service by Andrew
  Swan, Steven McCanne, and L.A. Rowe.Proc. of The
  Sixth Annual ACM Intl. Multimedia Conf.,
  September 1998.Best student paper
  award.http//bmrc.berkeley.edu/research/publicati
  ons/1998/148/148.html