Video Conferencing


Summer 1998

  1. What is Video Conferencing?
    1. d=>full motion interactive two-way or multi-way broadcasts.
    2. Point to Point
    3. Point to Multipoint
    4. Video Conferencing History
      1. 1960s-Picture Phone
      2. 1970s-Full-motion two-way close circuit and one-way noninteractive
      3. 1980s-Full-motion two-way interactive. Major breakthroughs:
    5. Video Conferencing Overview (people perspective)
      1. Increased managerial productivity
      2. Increased quality of meetings
      3. Improved quality of life
    6. Video Conference System Components
      1. Camera
      2. Monitors
      3. Audio
      4. Control System
      6. Communications Link (unchannelized T1, Fractional T1, satellite, microwave, etc.)
    7. Video Conference System Transmission Technologies
      1. Microwave
      2. Satellite
        1. C-Band
        2. Ku-Band
      3. Dishes
        1. antenna
        2. low-noise amplifier
        3. downconverter
    8. Bandwidth and Compression
      1. What can be compressed, lowered, or lost?
        1. Frame rate=> 30 frames per second (FPS) is broadcast quality.
        2. Luminance=> Light (contrast, brightness)
        3. Chrominance=> Color (depth of color, hue, saturation)
        4. Lossless vs. Lossy Compression
    9. Video Standards
      1. Px64
      2. JPEG
      3. MPEG
        1. MPEG1
        2. MPEG2
    10. Video Conference Standards
      1. H.320
      2. H.261
    11. Multipoint Control Units (MCUs)
    12. Connecting the Pieces
      1. Boardroom video conferencing systems
        1. Typically uses unchannelized T1 for 30 frames per second resolution or fractional T1 (384Kbps) for slightly lower quality.
        2. All equipment is "fixed" (permanently installed) in a room
        3. User interface on controller makes using camera presets and other equipment easier
        4. About $100,000 for all equipment, plus circuit charges per month
      2. Roll-about video conferencing systems
        1. System is on highly engineered cart that can be rolled into various rooms for flexibility in scheduling and maximum use of system
        2. Typically uses fractional T1 (128Kbps) for 15-20 frames per second resolution.
        3. Cost of system is around $25,000 for equipment, plus circuit charges per month.
      3. Desktop video conferencing systems
        1. Can operate over 28.8Kbps dial-up connection up to ISDN and/or LAN connections (4Mbps).
        2. Equipment ranges from $100 (Connectix Quick-Take) to $1500 (Intel ProShare or PictureTel desktop system) plus connect charges.
        3. Most systems deliver between 8 and 15 frames per second--relatively low quality video and sound.