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MPEG-2 Music Videos :-)

MPEG-2 Music Videos :-) Alan Crosswell alan@columbia.edu Outline The Content Network Issues Production Issues Show and Tell CODEC Issues and Requirements Outline The Content Network Issues Production Issues Show and Tell CODEC Issues and Requirements The Content

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MPEG-2 Music Videos :-)

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  1. MPEG-2 MusicVideos :-) Alan Crosswell alan@columbia.edu

  2. Outline • The Content • Network Issues • Production Issues • Show and Tell • CODEC Issues and Requirements Columbia University Academic Information Systems

  3. Outline • The Content • Network Issues • Production Issues • Show and Tell • CODEC Issues and Requirements Columbia University Academic Information Systems

  4. The Content • Violin Master Class – December 8, 2000 • Student: Wu Jie, at CANARIE in Ottawa. • Teachers: Pinchas Zukerman and Patinka Copec (of MSM) in New York (at Columbia). • Manhattan School of Music, CANARIE, National Research Centre, Natl Arts Centre. • Pt-to-Pt Litton CV2 MPEG2 & mcast MPEG1. Columbia University Academic Information Systems

  5. The Content • Dance Rehearsal/Conference – Jan 6, 01 • Peter Sparling Dance Company in Ann Arbor. • Association for Performing Arts Presenters conference in New York. • Demonstration/discussion of an in-progress commissioned work involving dances, costumes, set designs. Columbia University Academic Information Systems

  6. The Content • Cello Master Class – May 10, 2001 • David Geber of MSM in New York (at CU). • Erin Dunn at University of Oklahoma • YAML (Yet Another Music Lesson:-) Columbia University Academic Information Systems

  7. Outline • The Content • Network Issues • Production Issues • Show and Tell • CODEC Issues and Requirements Columbia University Academic Information Systems

  8. Network Issues • Campus network • 1% packet loss is not good enough w/CV2. • CV2 at 15.4 Mbps sends 16K PDUs via UDP: • 11 IP fragment Ethernet packets. • 352 ATM cells. • Drop one cell and the whole PDU's lost. • ATM issues - cell loss, policing, bursts. Columbia University Academic Information Systems

  9. Network Issues • Abilene/CANARIE ATM issues • Getting clobbered by QoS (shaping, policing). • ATM cell loss on NYCM OC-12 intf • Several sub-rate VCs. • OC-12 was not oversubscribed. • One 24 Mbps VC was heavily congested (JANET). • Caused head of line problems for other VCs. • Brent made it go away. Columbia University Academic Information Systems

  10. Network Issues • Some things to look for on campus: • 100-full duplex negotiated correctly? • Router ATM interface CRC errors? • ATM cell loss (policing, default burst length)? • Cisco PA-A3 (OC3 ATM) SAR HW 1.0? • Analog video causing Codec resets that convince you there’s a network problem. Columbia University Academic Information Systems

  11. Outline • The Content • Network Issues • Production Issues • Show and Tell • CODEC Issues and Requirements Columbia University Academic Information Systems

  12. Production Issues • Demos Harder than the “real thing.” • A large audience for a one-on-one event. • Added sound amplification adds echo. • Complicates echo cancellation. • Video monitors/projection screens. • Lighting for two-way video at the same time as projecting is goofy. Columbia University Academic Information Systems

  13. Production Issues • Audio • Emphasize audio over video quality. • Pops, squeals, screeches, drop-outs, echoes. • Audience will accept a few video artifacts. • Room-filling "rich" audio compensated for poor video in one event. Columbia University Academic Information Systems

  14. Production Issues • Audio engineers dealt with: • Room acoustics at both ends. • Drapes and foam where hung. • Gobos used to isolate codec fan noise. • Some echo is a good thing: room was too dead, so... • Remote echo was used to liven the room. Columbia University Academic Information Systems

  15. Production Issues • Audio echo avoidance • Can't use a voice-grade echo canceller for music. • Off-axis speaker/mic placement. • Gobos isolating mics from speakers. • Masking the backs of mics to control echo. • Muting ruins spontaneity. Columbia University Academic Information Systems

  16. Production Issues • Audio for world-class musicians • Doing audio for people who can hear the difference. • Frustrating not being able to directly monitor the remote room. • Maintaining a natural listening level. • Shaping of the audio by codec, etc. Columbia University Academic Information Systems

  17. Production Issues • Video (bush league) • Switching sources *must* have a time base corrector (e.g. video mixer). • A simple video switch causes a ~5 second CV2 encoder reset. • Which also kills the audio. • Bad video (loose connector) causes encoder resets which manifest as audio dropout. Columbia University Academic Information Systems

  18. Production Issues • Video • A prosumer mixer boasts 500 effects. • Don’t <BLINK>have</BLINK> to use them. • Prosumer mixer quality is just that. • PIP may show annoying artifacts. • Good lighting, camera quality and operator skill (get a pro video crew if it is important). • Plug a $200 camera into a $20,000 codec…. Columbia University Academic Information Systems

  19. Production Issues • “How do you get to Carnegie Hall?” • “Practice, Practice, Practice” • In a new campus location, begin testing one month beforehand to have plenty of time to deal issues that will come up. • When dealing with a new partner, there will be new routes and performance issues. • Both ends need to rehearse from the actual location of the event. Columbia University Academic Information Systems

  20. Outline • The Content • Network Issues • Production Issues • Show and Tell • CODEC Issues and Requirements Columbia University Academic Information Systems

  21. SKB portable rack The Road Show Columbia University Academic Information Systems

  22. SKB portable rack Flat panel drawer The Road Show Columbia University Academic Information Systems

  23. SKB portable rack Flat panel drawer Keyboard/mouse drawer The Road Show Columbia University Academic Information Systems

  24. SKB portable rack Flat panel drawer Keyboard/mouse drawer Video proc amp The Road Show Columbia University Academic Information Systems

  25. SKB portable rack Flat panel drawer Keyboard/mouse drawer Video proc amp Stereo mic/line mixer The Road Show Columbia University Academic Information Systems

  26. SKB portable rack Flat panel drawer Keyboard/mouse drawer Video proc amp Stereo mic/line mixer Stereo VU meter The Road Show Columbia University Academic Information Systems

  27. SKB portable rack Flat panel drawer Keyboard/mouse drawer Video proc amp Stereo mic/line mixer Stereo VU meter Litton CV2 MPEG-2 codec The Road Show Columbia University Academic Information Systems

  28. SKB portable rack Flat panel drawer Keyboard/mouse drawer Video proc amp Stereo mic/line mixer Stereo VU meter Litton CV2 MPEG-2 codec PC w/Z360 H.323 codec The Road Show Columbia University Academic Information Systems

  29. SKB portable rack Flat panel drawer Keyboard/mouse drawer Video proc amp Stereo mic/line mixer Stereo VU meter Litton CV2 MPEG-2 codec PC w/Z360 H.323 codec PC w/IPTV MPEG-1/2 The Road Show Columbia University Academic Information Systems

  30. Belkin PC switcher (remoted to kbd drawer) Video & Audio DAs The Road Show Columbia University Academic Information Systems

  31. Belkin PC switcher (remoted to kbd drawer) Video & Audio Das Audio/Video patch bay The Road Show Columbia University Academic Information Systems

  32. Belkin PC switcher (remoted to kbd drawer) Video & Audio Das Audio/Video patch bay Biamp echo canceller The Road Show Columbia University Academic Information Systems

  33. Belkin PC switcher (remoted to kbd drawer) Video & Audio Das Audio/Video patch bay Biamp echo canceller UPS The Road Show Columbia University Academic Information Systems

  34. Belkin PC switcher (remoted to kbd drawer) Video & Audio Das Audio/Video patch bay Biamp echo canceller UPS Still missing/unfinished: Headphone monitor DV capture Echo canceller + bypass The Road Show Columbia University Academic Information Systems

  35. Videonics MXPro DV :-( Canon GL1 camera. Tripod. Powerbook w/PPT for title slides (use S-video out). 2 SM57 mics. 2 Samsung VGA/Video 15" TFT monitors. 2 DELVCAM 5.6" TFT monitors. test generators (SMPTE bars, tone). miniDV recorder. 2 S-Video to S+Comp DA. lots and lots of cables. adapters. gaffers tape. The Road Show Columbia University Academic Information Systems

  36. The Road Show • Interfacing with the pros(umers) • Balanced vs. unbalanced audio (the audio engineers will get over it:-) • mic/line mixer with balanced XLR, TRS, mic and line jacks makes it easy. • Composite vs. S-video vs. component vs. firewire. • Chose S-video throughout the rack. • DV->analog conversion in the Videonics. Columbia University Academic Information Systems

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  38. Columbia University Academic Information Systems

  39. Outline • The Content • Network Issues • Production Issues • Show and Tell • CODEC Issues and Requirements Columbia University Academic Information Systems

  40. CODEC issues/reqs • Why are we using analog audio/video? • Audio requires better than CD quality: • 6 or more channels (e.g. Dolby 5.1, 7.1). • 96 kHz sampling. • "Perfect" audio/video synchronization. • Better than MP@ML (SDTV) • HD 1280p would be nice. • Firewire capture instead of analog? Columbia University Academic Information Systems

  41. CODEC issues/reqs • CODECs have to work with IP networks. • QoS-enabled. • RTP. • Dynamically adjust based on changing conditions. • Oh, and, by the way, deliver extremely low latency:-) Columbia University Academic Information Systems

  42. DV capture -> MPEG with Linux on a VAIO http://www.schirmacher.de/arne/dvgrab/ http://linux1394.sourceforge.net/ # modprobe ieee1394 # modprobe ohci1394 # modprobe raw1394 # modprobe sbp2_1394 # rescan-scsi-bus.sh # mount /dev/sda1 /mnt/disk # cd /mnt/disk # dvgrab --autosplit --format dv2 file Columbia University Academic Information Systems

  43. DV capture -> MPEG with Linux on a VAIO $ lav2yuv -I 1 file*.avi | mpeg2enc –o video.mpg $ lav2wav file*.avi | mp2enc -s -b 384 -r 48000 -o audio.mp3 $ mplex -o final.mpg video.mpg audio.mp3 $ gtv final.mpg Columbia University Academic Information Systems

  44. Columbia University Academic Information Systems

  45. Thanks…. • Lou Brown & Christianne Orto, Manhattan School of Music • Brent Sweeny, Grover Browning, Matt Davies & co., Abilene • Marc Boulerice, Jane Hermanson, Thomas Tam, CANARIE • Brian Shepard, Oklahoma University • Bill Owens, NYSERnet Columbia University Academic Information Systems

  46. Performance Copyright (p) 2000 Pinchas Zukerman, Manhattan School of Music, National Arts Centre of Canadawww.columbia.edu/acis/networks/advancedalan@columbia.edu Columbia University Academic Information Systems

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