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Behind the Curtain
Ben Fineman, Internet2
Networked Performing Arts
Photo by: R.A. Whiteside
Sight and Sound
Capturing Sight and Sound
Transmitting Sight and Sound
Two-wayTransmission
Two-wayTransmission:Advanced Networks
Capture
Capture Encode
Balancing Act
Balancing Act
Balancing Act: Quality
Balancing Act: Audio Quality
How Much
How Accurat
e
How Often
• How Often: Sampling Rate
Balancing Act: Sampling Rate
§ Limits frequency range
§ CD quality is 44.1 kHz
Balancing Act: Audio Quality
How Much
How Accurat
e
How Often
• How Accurate: Bit Depth
Balancing Act: Audio Quality
§ Limits quality
§ CD quality 16 bit = 65,536 levels
§ Studio quality 24 bit = 16,777,216 levels
Balancing Act: Audio Quality
How Much
How Accurat
e
How Often
• How Much: Bit Rate
How Accurat
e
44.1 kHz x 16 bit x 2 channels
= 1.41 Mbps
Balancing Act: Audio Quality
• “Compression” – making digital signals smaller
Balancing Act: Bit Rate
• Distinct from bit depth
• Many compression formats available
§ Lossy/lossless
§ Popular example: MP3
§ Popular consumer conferencing: Siren 14/22
Balancing Act: Audio Quality
Balancing Act: Video Quality
How Much
How Accurat
e
How Often
• How Often: Frame Rate
Balancing Act: Frame Rate
§ 60i: Standard for consumer broadcast/DVD/VHS, some HDTV
• Actually 59.94i, or 29.97 fps
§ 24p: Standard for film
§ 30p/60p: Some HDTV
§ Be aware of international differences!
Balancing Act: Video Quality
How Much
How Accurat
e
How Often
• How Accurate: Resolution
Resolution: How Accurate
Balancing Act: Video Quality
How Much
How Accurat
e
How Often
• How Much: Bit Rate
How Accurat
e
Balancing Act: Video Quality
Balancing Act: Video Quality
• Various compression formats available
§ MPEG-1, MPEG-2 (eg VCD, DVD)
§ MPEG-4 Part 2, MPEG-4 AVC/SVC
§ Microsoft: WMV, VC-1
§ H.263, H.264 (MPEG-4 AVC)
§ DV25
Balancing Act: Video Quality
Balancing Act
Balancing Act: Performance
Balancing Act: Performance
• How Fast
§ Network latency
§ Codec Latency
Latency
Balancing Act: Performance
Latency
Balancing Act
Balancing Act: Performance
• How Much (bit rate)
Balancing Act: Bandwidth
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Balancing Act: Bandwidth
0
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Capture Encode
DV camera DV camerawith audio inputs
Encode
Canopus ADVC-300
Canopus ADVC-700
Encode
SoftwareSend
Encode Send OK
Great
Poor
Encode SendPoor
Great
OK
Encode Send
VBrick
Digital River
TandbergTV
Poor
OK
Great
MPEG2
• Latency: Broadcast only (in general)
• Quality:
§ Audio: Compressed
§ Video: Compressed
• Bandwidth: 6 - 25 Mbps
Encode Send Polycom
Tandberg
Lifesize
OK
OK
OK
Encode Send
LOLA
UltraGrid/iHDTV
DVTS: What is it?
• “Open source” software developed by the WIDE Project (ie it’s free!)
• Sends firewire source over Internet with no additional compression
DVTS: Vital Stats
• Latency: Good enough for conversation
• Quality:
§ Audio: 48kHz/16 bit uncompressed
§ Video: Standard definition, DV25 compression
• Bandwidth: 30 Mbps
DVTS: What do I need?
• Capture: DV or standard camera
• Encode: In DV camera, or separate encoder
• Send: Computer running DVTS
• Transport: 30Mbps network
+ +
OK
OK
Great
ConferenceXP
• Latency: Good enough for conversation
• Quality:
§ Audio: Up to uncompressed
§ Video: Up to uncompressed
• Bandwidth: Variable, 1Mb to >30Mb
ConferenceXP
OK
Great
Great
LOLA
• Latency: Good enough for simultaneous performance
• Quality:
§ Audio: 44.1kHz, 24bit, uncompressed
§ Video: Up to uncompressed (SD)
• Bandwidth: 92Mbps to 460Mbps
LOLA
Great
Poor
Great
iHDTV/Ultragrid
• Latency: Good enough for conversation
• Quality:
§ Audio: 48kHz/16 bit uncompressed, 2+ channels
§ Video: 1080i HD, compressed or uncompressed
• Bandwidth: 250 Mbps to 1.5 Gbps
iHDTV/Ultragrid
OK
Poor
Great
Balancing Act
• H.323 Videoconferencing• Desktop Videoconferencing (eg Skype)
Balancing Act
• Many kinds of MPEG-2 and MPEG-4• Lossless compressions• HDDVTS
Balancing Act
• Uncompressed codecs• DVTS
Capture Encode Send Tansport
Tansport
• Appropriate Bandwidth
• Low or 0% loss
• Low or no jitter
• Multicast (if broadcasting)
Multicast
Unicast
Capture Encode Send Tansport Receive Decode
Receive Decode
Receive Decode
Software
Capture Encode Send Tansport Receive Decode Display
Display
DisplayEcho
Display Polycom
Tandberg
Lifesize
}AEC
Display
Polycom
Music Mode
Display
EchoDamp
RME Fireface 800
EchoDamp
Codec
Examples
New World Symphony: DVTS
Remote Master Classes: DVTS
DVTS: Example
DVTS: Example
DVTS: Example
Philadelphia Orchestra: MPEG2
MPEG2 Multicast
TandbergTV
Amino
Amino
Amino
HD-DVTS
Kinetic Shadows: MPEG2
MPEG2 Example
VBrick
VBrick
Display
Stage (Top down)
Screen
Screen
Screen
Capture
Display
Strategic Camera Position
Strategic Display Position
} Immersion
Adding Machine: DVTS
Stage (Top down)
Screen
Screen
Screen
Stage (Top down)
Screen
Screen
Screen
Arthron
Conference XP: Remote Instruction
ConferenceXP: Example
ConferenceXP: Example
Simultaneous Performance
Bitflow ALT-PCE-AN1
Industrial Camera
RME Fireface 800
Emerging Applications: iHDTV
• ResearchChannel along with the University of Washington
iHDTV/Ultragrid
1Gbps Ethernet 1Gbps Ethernet
1Gbps Ethernet 1Gbps Ethernet
Blackmagic Decklink
Aja Xena HS
2000 -> 2010
Uncompressed HD
Simultaneous Remote Performance
Real-time Screen Mapping
Emerging Applications: CineGrid 4k
1080
4k
0
2
4
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10
12
CineGrid 4k
• References
§ DTVS: http://www.internet2.edu/communities/dvts/
§ WIDE Project: http://www.sfc.wide.ad.jp/
§ New World Symphony: http://www.nws.edu/internet2/
§ iHDTV: http://www.washington.edu/ihdtv/
§ Ultragrid: http://dragon.maxgigapop.net/twiki/bin/view/DRAGON/UltraGrid
§ EchoDamp: http://echodamp.com/
• References
