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The Past, Present, and Future of Video Telephony: A Systems Perspective Dave Lindbergh Stanford The Past, Present, and Future of Video Telephony: A Systems Perspective Dave Lindbergh Stanford Networking Seminar 27 January 2005 1

Thanks to Athina for inviting me I’m going to take advantage of the opportunity Thanks to Athina for inviting me I’m going to take advantage of the opportunity to present some opinions about video telephony I hope at least they’re educated opinions Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 2

Contents A little bit about my perspective Where we’ve come from Where we are Contents A little bit about my perspective Where we’ve come from Where we are now – – – What is succeeding What is not succeeding (yet) Current problems & challenges The mass-market barrier – Expectations vs. reality – What it will take to succeed Where we go from here Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 3

A little bit about my perspective Engineering background – – Modems & data communications A little bit about my perspective Engineering background – – Modems & data communications Protocols, real-time systems, image processing 1993: Picture. Tel, largest vendor of video conferencing gear – ISDN, H. 320, H. 261 128+ kbit/s minimum Soon got sucked into standardization work – Mid-90 s: Chaired H. 324 Systems Experts Group • Edited ITU-T Rec. H. 324 • Basis of today’s 3 G-324 M system • Precursor to H. 323 (yes, I take some of the blame) Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 4

What I’ve been doing lately H. 264 video compression standardization – – Profiles/Levels Applications What I’ve been doing lately H. 264 video compression standardization – – Profiles/Levels Applications Editor, ITU-T Rec. H. 239 – Role management – – Live = People Presentation = Content Editor, ITU-T Rec. H. 241 – Video signaling Editor, H. 324 (again) Rapporteur, ITU-T Q. 23/16 (“Media Coding”) Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 5

Video telephony system 18 frames/second Progressive scan Plasma display Pixel aspect ratio 3: 2 Video telephony system 18 frames/second Progressive scan Plasma display Pixel aspect ratio 3: 2 Image quality described as “excellent” End-to-end latency 1 millisecond (great!) Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 6

April 7, 1927 – Bell Labs Past, Present, and Future of Video Telephony – April 7, 1927 – Bell Labs Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 7

New York – Washington DC Walter Gifford President, AT&T New York Herbert Hoover US New York – Washington DC Walter Gifford President, AT&T New York Herbert Hoover US Sec’y of Commerce Washington DC Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 8

“Television” = Telephone + Vision 50 x 50 pixel display, neon bulbs Camera: Scanning “Television” = Telephone + Vision 50 x 50 pixel display, neon bulbs Camera: Scanning arc lamp beam Optional projection to 2 x 3 feet – But “results were not so good” Edna Mae Horner Operator Chesapeake and Potomac Telephone Company Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 9

AT&T Picturephone 1957 “Experimental Model” Past, Present, and Future of Video Telephony – Lindbergh AT&T Picturephone 1957 “Experimental Model” Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 10

Early 1960 s Mirror Past, Present, and Future of Video Telephony – Lindbergh – Early 1960 s Mirror Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 11

AT&T was very serious Plenty of smart business people! 1964 Past, Present, and Future AT&T was very serious Plenty of smart business people! 1964 Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 12

Framing Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford Framing Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 13

Did it “cost too much”? AT&T finally gave up in the early 1970 s Did it “cost too much”? AT&T finally gave up in the early 1970 s Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 14

1980 s – Still image picture phones Mid-1980 s: Japanese consumer electronic firms introduced 1980 s – Still image picture phones Mid-1980 s: Japanese consumer electronic firms introduced still-image picture phone – – – Used existing regular analog phone line POTS modem ~ 5 seconds to send 1 black & white frame No audio during picture transmission ~$200 each Very few takers Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 15

1992 – AT&T Videophone 2500 “Predicting that 10 years from now video phones will 1992 – AT&T Videophone 2500 “Predicting that 10 years from now video phones will be as popular as cordless phones and fax machines, last week AT&T introduced the first full-color motion video phone that operates over regular phone lines…AT&T officials say the picture quality was acceptable to test-market consumers” – Newsweek, January 20, 1992 10 frames/second, $1500 Marconi, others, had similar products Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 16

Many more videophones since then Mostly based on ITU-T standards H. 320 (ISDN) H. Many more videophones since then Mostly based on ITU-T standards H. 320 (ISDN) H. 323 (IP) H. 324 (POTS) and SIP They all worked Siemens T-View H. 320 (ISDN) Phone 1997 Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 17

More videophones Past, Present, and Future of Video Telephony – Lindbergh – January 2005, More videophones Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 18

And more… Past, Present, and Future of Video Telephony – Lindbergh – January 2005, And more… Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 19

And more Past, Present, and Future of Video Telephony – Lindbergh – January 2005, And more Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 20

FOMA experience in Japan FOMA = H. 324/Mobile, 64 kbit/s channels Video calls cost FOMA experience in Japan FOMA = H. 324/Mobile, 64 kbit/s channels Video calls cost ~2 x price of voice calls 3 million phones deployed (as of Sept. 2004) Average monthly video usage = 2 minutes Top 20% of users do 20 minutes/month Most users young – Show where they are, who they’re with – Don’t point camera at themselves Do. Co. Mo is hopeful that usage will increase when penetration > 1 phone/family Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 21

Still-image camera phones 2 nd generation – Camera is on back of phone Past, Still-image camera phones 2 nd generation – Camera is on back of phone Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 22

Did they all cost too much? Many had good video quality Most were reliable Did they all cost too much? Many had good video quality Most were reliable & easy to use Many < $50 PC cameras with videophone apps MS Net. Meeting & Messenger are free Clearly, people do want video phones – Witness all the attempts, user excitement But they don’t buy or use them when offered – For some reason people are disappointed – We need to understand why before we can fix this Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 23

What is succeeding? The real killer app: TELEVISION But TV is doing fine without What is succeeding? The real killer app: TELEVISION But TV is doing fine without help from me… Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 24

What else is succeeding? Video conferencing – – $2 B/year industry, profitable Top vendors: What else is succeeding? Video conferencing – – $2 B/year industry, profitable Top vendors: Polycom, Tandberg, Sony Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 25

Video conferencing today Most use is in large organizations – – – Industry Government Video conferencing today Most use is in large organizations – – – Industry Government Education Most use is internal – Between sites of the same organization Most use is scheduled – Planned meetings, not spontaneous Only a few meeting rooms have VC equipment – Much talk about ubiquitous access, but not real yet Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 26

Situations where VC works well With people you already know – Already introduced, not Situations where VC works well With people you already know – Already introduced, not strangers Not too many people on screen at once – Need to see facial expressions clearly Good lighting Good room & furniture layout People & Content at same time How I use it every week – Offices in Boston, California, Texas, Atlanta, Israel… Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 27

Why is VC successful? Relatively big picture size, high resolution – Less restriction on Why is VC successful? Relatively big picture size, high resolution – Less restriction on where people are in the frame Good lighting High-value application Work environment, pre-scheduled meetings – People come dressed & prepared to meet others – Reduces discomfort with “being on camera” Yet, VC is still in < 2% of conference rooms – Lots of room for growth – Similar problems as stopped video telephony – It works, but not nearly as well as we want it to! Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 28

How are we doing? We’re doing an excellent job on the classical technical challenges How are we doing? We’re doing an excellent job on the classical technical challenges – – Video and audio coding Cost: $250 K (1989) to $2000 (2004), less for PCs Bandwidth is getting cheaper all the time Simplicity, reliability have improved greatly Some immediate challenges – Standards and network issues – being worked Longer-term challenges for video telephony – Expectations vs. reality – Human factors Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 29

Standards Wonderful thing: So many to choose from! Religion: H. 323, SIP, MGCP, proprietary… Standards Wonderful thing: So many to choose from! Religion: H. 323, SIP, MGCP, proprietary… – No real differences from user perspective – Some want to start over…again Every standard is unnecessarily complex – – – Over-reaction to past mistakes, too little experience The POTS network was also incredibly complex Limits of human complexity management ability Directory services – ENUM/DNS, H. 350/LDAP, UMMAP… – This will settle out with time Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 30

Latency Lots of denial – this is not helpful ITU-T G. 114 gives 150 Latency Lots of denial – this is not helpful ITU-T G. 114 gives 150 ms as an upper limit – For total end-to-end latency • • Including propagation over distance This is about right, but difficult to achieve IP networks inherently have latency issues – Usually make ARQ, backchannel schemes impractical Low frame rates make things worse Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 31

Quality of Service on IP Lots of solutions in theory – Diff. Serv, MPLS, Quality of Service on IP Lots of solutions in theory – Diff. Serv, MPLS, IP Precedence, etc… Zero penetration on public Internet – There is no pricing model Most private networks provide Qo. S with massive over-provisioning – This is often cheaper than “clever” schemes Qo. S will remain a problem on the public Internet until there is a way to charge for it Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 32

More network issues NATs and Firewalls – – IP is effectively unusable between organizations More network issues NATs and Firewalls – – IP is effectively unusable between organizations Virtually all inter-organization calls are still ISDN Network fragmentation – – IP, ISDN, POTS, 3 G, 4 G… Lack of public/automatic gateways These are all being worked; will get solved – Some things will take time to shake out A “killer app” could force more rapid change – But this hasn’t happened yet Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 33

Video compression coding Ideal lossy video compression system – Every possible bit sequence decodes Video compression coding Ideal lossy video compression system – Every possible bit sequence decodes as something meaningful to human perception – On various time scales – Might this be the way the brain works? • Markov chain text generators sound a lot like dreams… Lots of room for improved coding Past: Biggest challenge was reducing bitrate – Bandwidth and storage were expensive Today: Computational efficiency a challenge – Bits are getting cheaper faster than computes are Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 34

Beyond video coding Most video research focused on coding – Without compression video was Beyond video coding Most video research focused on coding – Without compression video was unmanageable Between improved compression and cheaper bandwidth and storage, things can now change – Computation has gotten much cheaper Fast, cheap video DSP means we can do more – – Stitching, warping, perspective correction… Searching, indexing, processing, recognizing content Analogous to audio & still-image DSP – There will be new apps unique to video Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 35

The mass-market barrier Video conferencing is a successful niche Video telephony hasn’t succeeded yet The mass-market barrier Video conferencing is a successful niche Video telephony hasn’t succeeded yet – Yet, clearly there is a market desire! Current issues don’t explain past failures – Standards, directories were solved for videophones – Latency was not a problem in the analog world – Qo. S, NAT/FW issues didn’t exist for switched circuits Then what will it take for success? – Why have users not yet embraced video telephony? Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 36

What will it take to succeed? Cost? – PC apps are nearly free, yet What will it take to succeed? Cost? – PC apps are nearly free, yet very little used Reliability? – Current systems work well on private networks – Video telephones were quite reliable Complexity? – Video phones are easy to use, as are modern VCS Video quality? – VC systems provide TV-like quality, yet haven’t broken into the mass-market Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 37

Expectations – Fiction Metropolis (Fritz Lang, 1926) Past, Present, and Future of Video Telephony Expectations – Fiction Metropolis (Fritz Lang, 1926) Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 38

From Jetsons to Star Trek Countless science-fiction films & TV shows – Perfect framing, From Jetsons to Star Trek Countless science-fiction films & TV shows – Perfect framing, perfect lighting – People look straight into the camera – Nobody is nervous “being on camera” 2001: A Space Odyssey (Stanley Kubrick, 1968) Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 39

Expectations – Film & TV experience We’ve all grown up with film & TV Expectations – Film & TV experience We’ve all grown up with film & TV – – Professional cinematography / videography Studios with proper lighting, layout Multiple camera angles Directors to choose the best shots With video telephony we get – – – Single camera viewpoint Bad lighting Bad or no framing Often, poor resolution and video quality Sometimes, tiny pictures Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 40

What it will take: Human factors Framing – Keeping people in the picture Camera What it will take: Human factors Framing – Keeping people in the picture Camera viewpoint & perspective – Psychological factors, geometrical distortion Eye contact & gaze direction – And “camera shyness” Peripheral vision – Sense of space – close-up vs. wide views Attention requirements – Tradeoffs of different media Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 41

Framing Keeping people in the picture – – – Close enough to see faces Framing Keeping people in the picture – – – Close enough to see faces clearly Far enough for freedom of movement Consciousness of framing, control can be distracting – Scenes in movie Mother (Albert Brooks, 1996) – Rob Morrow and Debbie Reynolds on videophone Automatic speaker-following not ideal – – – Often used when multiple people are in the room Want to see listener reactions (not just talker) Want to see VIPs (even if they’re listening) Close-ups can lose sense of relative position Still, often better than doing nothing Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 42

Camera viewpoint & perspective If the camera is too close – Geometric distortion – Camera viewpoint & perspective If the camera is too close – Geometric distortion – big noses, etc. If your camera is above eye-level – They’re looking down on you – you look submissive If your camera is below eye-level – They’re looking up at you – you look dominant This is why royal thrones are tall There is no single “right” position – People can either stand or sit Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 43

Eye contact What happens when you stare at someone? Does it happen if you Eye contact What happens when you stare at someone? Does it happen if you stare at video? What happens when someone stares at you? – Do you feel comfortable? Eye contact is a form of innate, highly evolved non-verbal communication – A deep part of human nature – Lots of emotional charge – Not present in video telephony - unnatural Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 44

Eye contact & gaze direction People can detect eye contact at great distances – Eye contact & gaze direction People can detect eye contact at great distances – – They can tell when they’re being observed They may respond with a glance, or return contact Cooperation or liking = more direct gaze Disagreement or dislike = less direct gaze Gaze and emotional signals – – – Unwavering gaze - dominance or threat Gaze avoidance – submission or fear Gaze can signal sincerity, discomfort, challenge… Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 45

Eye contact and video We need to solve eye contact on video – I Eye contact and video We need to solve eye contact on video – I think this will reduce “camera shyness” Need to know who is looking at you Need to know if/when you’re stared at Need to allow natural feedback response Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 46

Other “naturalness” issues Peripheral vision – Noticing what other people are doing Many people Other “naturalness” issues Peripheral vision – Noticing what other people are doing Many people prefer to see but not be seen – At least with current video systems Attention demand & media – – Text: Least – can carry on several IMs at once Audio: More – one at a time, can do other things Video: Most – can’t do other things Not a flaw, just something to take into account Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 47

Why is this all so complicated? Voice telephony doesn’t have these problems Because people Why is this all so complicated? Voice telephony doesn’t have these problems Because people are evolved to talk in the dark – This is why telephones “work” Because video is not “just another channel” – But that’s how engineers usually think about it – It’s something very different than audio The video telephony experience needs to feel more natural and intuitive – I think this is the real reason it hasn’t succeeded yet – This is where research needs to focus Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 48

We are still in the “mainframe” era Video telephony is not unique in facing We are still in the “mainframe” era Video telephony is not unique in facing this challenge – Automobiles: Benz Motorwagen to Ford Model T • Mass production, simplicity – Aviation: Wright Flyer to Douglas DC-3 • Efficiency, safety – Computing: Mainframes to PCs • VLSI microprocessors From possibilities in theory to useful practice – – – High-value niche applications come first These teach us about what is missing When technology matures, the mass-market arrives Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 49

Where we go from here “Show-me” 3 G video phones can succeed now – Where we go from here “Show-me” 3 G video phones can succeed now – – See where I am See who I’m with Human factors issues not a problem in this model Limited usage compared to voice minutes Video conferencing, other high-value apps will continue to mature & expand Human factors improvements needed – For “talking heads” video telephony to succeed A fertile field for research – please work on it! Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 50

It may take a visionary individual ? Past, Present, and Future of Video Telephony It may take a visionary individual ? Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 51

Thank you! Polycom has an opening for a video DSP researcher to work on Thank you! Polycom has an opening for a video DSP researcher to work on these topics Send CVs to [email protected] F 1. com Past, Present, and Future of Video Telephony – Lindbergh – January 2005, Stanford University 52