Slides - Terena

DVTS (practical) Overview
Claudio Allocchio, GARR
with many contributions by Ben Fineman (Internet2) and by the
DVTS team (Keio Media Design)
Network Performing Arts Production Workshop, Vienna, March 2013
Summary
  Some basic concepts
  DVTS Overview
  Emerging Applications
From Analog to Digital
Audio: Sampling Rate
  Limits frequency range
  CD quality is 44.1 kHz
Audio: bits depth
  Limits quality
  CD quality 16 bit = 65,536 llevels
Audio & Video:
  “Compression” – making digital signals smaller
Audio: Bit Rate
  Distinct from bit depth
  Many compression formats available
  Lossy/lossless
  Popular example: MP3
  Popular consumer conferencing: Siren 14/22
Video: 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!
PAL, SECAM, NTSC
Video: Resolution
Video: Compression
Video: compression formats
 
 
 
 
 
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
How long does it take…?
Latency
  How Fast
  Network latency
  Codec Latency
Latency: what can I do?
Latency
Simultaneous
Performance
Conversation
Broadcast Only
How Much does it take? Bandwidth
DVTS: What is it?
  “Open source” software developed by the WIDE
Project (it’s free!)
  Sends firewire source over Internet with no
additional compression
  A 30Mbps “long pipe” between firewire interfaces
DVTS: quick Features Sheet
  Latency: Good enough for conversation
  Quality:
  Audio: 48kHz/16 bit uncompressed
  Video: Standard definition, DV25 compression
  Bandwidth: 30 Mbps
DVTS: Why?
  Because you can send & receive High
Quality A/V
  that doesn’t require funny, expensive machines (MPEG2)
  that doesn’t involve intellectual property issues (royalties)
  that doesn’t require unusual, expensive cameras (HDTV)
  all you need is a 30Mbps capable Network
and …
  a DV capable camera with IEEE1394 (firewire)
  DV receiver (deck, camera, TV) that is firewire capable
  Or an analog/digital converter(s) if using a non-firewire capable
camera/receiver (Canopus ADVC family)
  a computer with IEEE1394 (firewire) capability
16
3/8/13
DV: a more technical specification
  DV25 is a common form of digital video reduction and
compression employed in consumer digital camcorders
  DV25 applies a 5:1 compression and a 4:1:1 color space;
achieves a fixed data rate of 25 mbps
  Audio is typically two-channel PCM encoded at 12 or 16
bits, sampled at 48kHz, similar to CD or DAT
  DV25 achieves relatively high audio and picture quality
with very low encoding latency.
  End-to-end quality is fully preserved: No additional
compression/decompression is added
17
3/8/13
DVTS: from “A” to “B”
A
Capture
Encode
Send
Receive
Decode
Display
B
DVTS: minimal requirement
  Computer (runs best on Windows but Mac and
Unix versions exist)
  Camera or encoder with firewire output
  30 Mbps of bandwidth
+
+
DVTS caveat 1: which firewire?
 
Connects the camera to the computer
 
Provides high quality digital path
  “Firewire” developed by Apple Computer
  It is really a high-speed serial data bus
  IEEE 1394 is the published specification for highspeed serial bus
  Firewire 400
  400 Mbit/s over a distance of 4.5M
  Double twisted pair, 28 AWG wire
  Longer distance possible using higher gauges and
slower data rates
  Firewire 800
  800 Mbit/s over a distance of 100M
20
3/8/13
DVTS: capturing image and sound
Choose one or more:
Capture
DVTS: encoding with DV cameras
DV camera
Capture
Encode
DV camera
with audio inputs
DVTS: encoding from analog source
Choose one:
Canopus ADVC-300
Encode
Canopus ADVC-700
DVTS: sending
Choose one:
Send
+
DVTS: Platforms
Hardware
Port built-in
Multiple firewire
port support
no
Macintosh Intel
OSX
Pentium III or greater Windows XP
Port built-in
PC firewire card or built in
no
yes
Pentium III or greater
PC firewire card or built in
no
Macintosh Power PC
Operating
System
OSX
Linux
IEEE 1394/Firewire
  The chef reccomends:
  Intel duo Processor @ 2Ghz
  2GB RAM
  Windows XP or Windows 7
25
3/8/13
DVTS: Software versions
Command line applications
Operating
System dvsend dvrecv dvsave dvplay
GUI application
App
Name
Firewire Firewire Render to
Send Receive screen
Mac OSX
yes
yes
yes
yes
dvts.app*
yes
yes
no
Windows
XP/Vista/7
no
no
no
no
dvts.exe
yes
yes
yes
LINUX
yes
yes
yes
yes
-
-
-
-
* This application is VERY alpha release level
26
3/8/13
DVTS: the transport
Send
Transport
  30 Mbps
  0% loss
  Multicast (if broadcasting)
Receive
DVTS: receiving
Choose one:
Receive
+
DVTS: decoding, simple mode
Choose one:
Receive
+
Decode
+
DVTS: decoding, to analog devices
Choose one:
Canopus ADVC-300
Decode
Canopus ADVC-700
Camera
DVTS: simple render/display
Receive
+
Decode
Display
+
DVTS: better render/display
Choose one or more:
Display
DVTS caveat 2: PAL vs NTSC !
  SD (standard defintion) is MORE than 1 standard!
 
PAL and NTSC are incompatible!
  You need multi-standard devices
  At least multi-standard decoder/display/projector
  DVTS cannot switch on the fly PAL and NTSC standard
  You MUST quit DVTS before switching standard
  Self test to yourself, then connection to/from a different standard
system = FAIL!
  … and what about SECAM ?
  No DVTS for SECAM, sorry!
33
3/8/13
DVTS: echo?
= echo
Display
= no echo
+
= no echo
DVTS: simple example
DVTS: full example
DVTS: broadcasting example
DVTS: Multicast
Multicast
Unicast
DVTS Revisited !
DVTS: some Resources
  Internet2:
http://www.internet2.edu/communities/dvts/
  WIDE Project:
http://www.sfc.wide.ad.jp/DVTS/
  Keio Media Design uhyo.org:
http://www.uhyo.org/dvts/index.html
  New World Symphony:
http://www.nws.edu/internet2/
DVTS: some Contacts
 
 
 
 
 
Ann Doyle -- [email protected]
Ben Fineman – [email protected]
Justin Trieger – [email protected]
Claudio Allocchio – [email protected]
Kazunori UHYO Sugiura - [email protected]
DVTS: Applications
 
 
 
 
 
 
 
Remote
Remote
Remote
Remote
…
Remote
…
instruction
performance
recording
collaboration
Health Services
DVTS: Applications
Don’t Forget
Echo avoidance
Lighting
HDDVTS: What’s it about
  Latency: Broadcast only
  Quality:
  Audio: 384 Kbps MPEG-1 layer 2
  Video: 1080i MPEG-2
  Bandwidth: 25 Mbps
Questions?