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1. Introduction |
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Internet TV with CU-SeeMe: Chapter 1 - Introduction
Introduction to Internet Videoconferencing and CU-SeeMe
After you read this chapter, you will know
What Is Internet Videoconferencing?
You're busy doing your work, writing papers, checking email, and juggling numbers in a spreadsheet, when a window pops up on your screen. It's someone you know. You see him, and he sees you. You speak with him, all the while gesticulating wildly to emphasize a point. Ideas are exchanged, a dinner date is made, and the conversation ends. You both hang up and go back to work. Videoconferencing in action.
Computer-based videoconferencing is startling. It redefines your relationship with your computer and, more importantly, how you communicate electronically with other people around the world on the Internet and on private networks. My first experience with computer-based videoconference was as amazing as using the first Macintosh (the Lisa) was, over a decade earlier. The first time I visited a videoconferencing watering hole on the Internet - a reflector - was through my employer's high-speed network. Eight small flickering moving pictures appeared - people from all over the world gathering at the same virtual spot. The images were grainy collections of eight-pixel-square sections, each one of which was updated as the image changed, resulting in a strobe-light dance floor effect. Six faces peered at me. Two windows contained images of the outdoors: the New York State Thruway and a building being constructed in Manhattan. Here are some images taken from CU-SeeMe sessions:
My initial nervousness at seeing faces was quickly replaced by the excitement of seeing people. It's a strange feeling to see people and to try to extract meaning and personality from the choices people make regarding hair and clothing style, office knick-knacks, and the method of scribbling on the inevitable office whiteboards behind the talking heads.
Only a few of us had audio capability. The sound came through my stereo speakers in fits and starts - squacking, barely intelligible speech that was often cut off as the company-wide network became filled with a burst of information from people doing real work. To compensate, we would type notes to one another in our video windows. We could barely push enough information into these conversations to become misunderstood. The novelty of connecting to people on the other side of the planet was sufficient.
Despite small black and white images, distorted sounds, and misspelled words, it was novel enough - even thrilling - to connect to and communicate with people from all over the planet. I shared the joy of anticipation of the birth of a video acquaintance's first child, expressed in a last-minute conversation before he rushed off to the hospital in Perth, Australia. I saw the inhabitants of a house-on-the-Net live, work, and vacuum the floors. I saw people at work, reaching out to others on the Internet. We communicated.
Videoconferencing over the Internet doesn't have to be simply two-way communication between people. Breathlessly, I watched live video of the Earth turning under the space shuttle while astronauts danced in the opened cargo bay, sending a satellite on its way. Stunned, I watched a huge effigy of a human figure set on fire in the annual Burning Man festival in the Nevada desert (see Figure 1.7).
Bemused, I watched the antics of Britons at a night club, broadcast all over the world for those of us still at the office to enjoy. With a feeling of fragile connectedness, I watched the changing scenes of our planet, one live feed per continent, disseminated to celebrate the twenty-fifth anniversary of Earth Day. With horror, I watched live footage of the aftermath of the bombing of the federal office building in Oklahoma City (see Figure 1.8). With great curiosity, I watched the proceedings of parliamentary deliberations in other countries.
While authoring some World Wide Web pages in 1993, I wrote that CU-SeeMe has me more excited about being part of the global village than anything that has come before it. The phrase "interactive desktop - laptop? - videoconferencing" doesn't do it justice; it simply describes the basic vehicle being used. More important, however, is the tremendous potential it has for connecting us over the Internet in ways not possible until now: global, interactive, multi-sensory human communication and collaboration by the computer-equipped masses. That's the experience we're heading toward. The ability to see and hear fellow Internauts has made me acutely aware of the other people with whom I share this planet.
Through years of encountering the same people repeatedly in nonvisual media - such as the frequent contributors to the USENET newsgroups that I read - I had in my mind's eye an image of them. Pleasantly, unlike movies and television, which tend to erode the imagination inspired through earlier media such as books and radio, I find that two-way video adds to the feeling of kinship that I've built up with people who I've never before heard or seen. In this book, I'll show you how to join me and, indeed, all of us in the already large and fast-growing Internet videoconferencing community.
Videoconferencing enables you to communicate by means of typed text, audio, and video across a computer network (such as your company's private IP network) or the world-wide Internet. You decide whether to be a sender, a receiver, or both.
Plenty of people want to broadcast to the world. The offerings have been interesting - and are getting more so every day. The individual and small group possibilities inherent in being able to transmit specialized audio and video promises to be an educational and recreational tool of great impact. Children following the GlobalSchoolNet's Where in the World is Roger? - a trek around the world by a man and his truck that is broadcast from various stopping-points via CU-SeeMe - have been transported in an interactive way with their counterparts in Europe and Asia.
What Is CU-SeeMe?
CU-SeeMe - pronounced "See you, See me" - is a videoconferencing system developed at Cornell University - the CU in CU-SeeMe. It works on the Internet or any network that uses Internet Protocol (IP). Macintosh and Windows clients are currently available, and CU-SeeMe may be ported to more computers now that the source code is available to interested parties.
CU-SeeMe users can connect directly to one another in a point-to-point manner, or they can connect to a group conference by connecting to a reflector - a UNIX computer running software that redistributes the audio and video streams to everyone connected. Basic connection methods are described in Chapter 2, Typical CU-SeeMe Usage.
The only things required to view incoming video are a video monitor (computer display) capable of providing 16 levels of gray or color and a connection to a network using IP - either a private network or the Internet itself. To transmit video to others requires only a video-camera and a digitizer board. Some computers, such as AV Macintoshes, have a video digitizer built in. A camera/digitizer package is available for Macintosh and Windows computers in a combined golf-ball-sized package for under $100. CU-SeeMe video is 16-level (4-bit) grayscale, as shown by the arrow in Figure 1.9. Color CU-SeeMe will appear in the near future.
Video resolution is available in two choices (shown in Figures 1.9a and 1.9b): high-quality 320 by 240 pixels - which is half the diameter of NTSC television - or low-quality 160 by 120 pixels. The high-quality video is available only for Macintosh-to-Macintosh connections. The Windows version currently supports only low-resolution video.
??? FRAN: Figures 1.9a and 1.9b should be Figure 1.10 (if combined) or 1.10 and 1.11 (if separate). -horman
Figures 1.9a and 1.9b. High-resolution and low-resolution video.
??? FRAN: Figure 1.9a and 1.9b should be Figure 1.10 (if combined) or 1.10 and 1.11 (if separate).
Figure 1.10. High-resolution video.
Figure 1.11. Low-resolution video.
-horman
***Begin Note***
NTSC (National Television System Committee) is one standard for the transmission of video signals. It is not the only one, however. Depending upon where you live in the world - or how much hardware you collect - you will come across NTSC, PAL, and SECAM.
NTSC was developed in the United States in 1953. It is used throughout North America, in some countries in South America, and in Japan. NTSC uses color images of 525 horizontal lines of resolution at 30 frames per second.
PAL (Phase Alternation by Line) was developed in Germany and adopted in 1967. It is used in much of Europe, Africa, the Middle East, and Far East. PAL uses color images at 625 horizontal lines of resolution - except in Brazil, where PAL-M is used - and supports 30 frames per second with 525 horizontal lines of resolution. PAL is the most widely used and supported color video standard.
SECAM (Syste[ag]me Electronique Couleur avec Memoire) was adopted in 1967. It enjoys scattered use throughout the world, in the former Soviet Union, and in areas of French influence. SECAM uses color images of 625 lines of resolution at 25 frames per second.
These standards become important when you're purchasing hardware to convert images from your video camera to a form that your computer can use and transmit. Some hardware understands only one standard; other hardware can automatically recognize the standard used by the video source and can handle the signal accordingly.
Many countries support more than one standard. HDTV (High-Definition TeleVision), with all its competing standards, hasn't yet become a factor in Internet videoconferencing.
***End Note***
The capability to transmit sound between conferencees is available on both the Macintosh and Windows versions of CU-SeeMe. The quality of the audio is limited by a combination of the computer's basic horsepower (processor, memory, and I/O bus speed), the connection method and speed, and the audio capture capability (the quality of the audio capture board, speakers, and microphone).
The connection method determines the amount of sound and video data that can be sent to and from the computer. Faster connections - that is, greater bandwidths - are preferable to slower ones. The computer's speed determines which sound encoding method can be used. Because everything must be done in real time if the conversation is to be understandable, a faster computer can use a more efficient encoding method and can get more sound into the available bandwidth.
Telephone-quality audio, when encoded with a method available to a system running at the speed of a typical Macintosh or Windows computer, requires about 16K of information per second (kbps) be sent. A 14,400 kbps modem clearly cannot provide the necessary bandwidth for audio - to say nothing of video. A 28,800 kbps modem is just barely enough to carry audio. ISDN, discussed in Chapter 4, Hardware, can carry audio and video simultaneously. Fiber optic cable, with its megabit bandwidth, will be deployed by U.S. cable television companies to households across the country. This will provide more than enough bandwidth for the current requirements of videoconferencing. By that time, though, we will expect color, stereo sound, and other bandwidth-eating developments.
Another factor in audio transmission quality is whether the audio capture/play hardware supports full-duplex or half-duplex audio. Full-duplex audio enables the simultaneous capture of audio that you are sending and the play of audio that you are receiving, much like a telephone. Half-duplex audio enables only one or the other at a time. You can speak - in which case the playback of audio being received from others is blocked - or you can hear the audio being received from others but not transmit.
Half-duplex audio conversations can be compared to the conversation you have over a walkie-talkie, CB radio, or a typical, low-end speaker phone used for audioconferencing over telephone lines. The off-the-shelf audio support built into every Macintosh is full-duplex. Intel-based PCs are dependent on the board used; some boards available for the PC, such as Media Vision's Pro Audio Spectrum, support full-duplex audio. Most low-end boards support only half-duplex audio.
To gain a bit of perspective, consider this. Six months ago, 32 kbps were required to transmit audio. Today, only 16 kbps are required, thanks to better software compression technology. As raw computing power increases, your computer of tomorrow will be able to perform even more complex decompression in real time, lowering yet again the bandwidth requirements for sending audio. As connections get faster and compression gets better, you will be able to get stereo sound and who knows what else.
***Begin Note***
CU-SeeMe was never intended to operate on low-bandwidth (modem) connections. Its developers were connected with a 10 megabit Ethernet network, and they expected the same of CU-SeeMe users. In spite of this, people have found ingenious ways of making CU-SeeMe usable over 14.4 kbps modems. They've found satisfaction by typing instead of speaking and by configuring CU-SeeMe to use a slower refresh rate (discussed in Chapter 6, CU-SeeMe User's Guide.
Even at one frame every 10 to 15 seconds over a 9.6 kbps connection, CU-SeeMe can still prove to be an effective visual communication tool in situations such as a presentation, where the image being received doesn't change frequently. Even in situations where the scene being captured changes frequently, a periodic sampling of the image is often surprisingly adequate.
***End Note***
CU-SeeMe's audio capabilities have been taken from Charlie Kline's program called Maven. Charlie continues to upgrade Maven, and he has recently added even more audio encoding features. CU-SeeMe and Maven can be used in tandem. (Before CU-SeeMe provided audio, this was how CU-SeeMe pioneers spoke to one another.)
CU-SeeMe has a built-in method for extending its capabilities: the Auxiliary Data Function Module system, which is described in Chapter 6, CU-SeeMe User's Guide. Plug-ins currently available include
Timothy Dorcey, the co-creator of CU-SeeMe, wrote: "The main objective in the development of CU-SeeMe was to produce an inexpensive videoconferencing tool that would be usable today. As well as providing direct benefit to its users, we expected that valuable lessons could be learned about how videoconferencing actually works in practice, how the experience should be organized, what features are necessary to support multi-party conferencing, and so on. While others worked to advance the state of the art in video compression, high-speed networking, and other low-level technologies necessary to support high quality videoconferencing, we hoped to facilitate the accumulation of experience that would provide impetus for those efforts and guide their direction."
CU-SeeMe has done this and more. Throughout this book, you will find evidence of the body of understanding that we have learned due to widespread use of CU-SeeMe. Some of the knowledge has to do with responsible use of network bandwidth; other knowledge is much more anecdotal and less quantitative.
Why CU-SeeMe?
There are many videoconferencing options, including hardware and software combinations that cost about $100 for a complete system and others that cost many thousands of dollars per seat/room. Dedicated high-end systems can easily run into the hundreds of thousands of dollars for a virtual conference room system, such as the ones at Hewlett Packard. A handful run over TCP/IP; they include CU-SeeMe, NV, VidCall, and Intel Proshare. Others, such as PictureTel and Creative Labs, use H.320 and proprietary solutions. Each option has advantages and drawbacks.
CU-SeeMe is well known in the Internet community, has been extensively used over the last few years, and can be had for free. Commercial, supported versions will shortly be available from White Pine, the master licensee of the CU-SeeMe technology).
One great advantage to using CU-SeeMe is that, because it runs over TCP/IP, you can use it on the same computer system that you use for virtually all your other telecommunications needs - email, reading USENET newsgroups, and so on. Dedicated systems tie up one of your telephone lines if you're an at-home user of CU-SeeMe and don't enable you to do any other Net-surfing. Other systems don't allow multi-point connections and the ad-hoc assemblage of users.
Timothy Dorcey forwarded to me the final part of an email conversation he had had with an employee of Pacific Bell. It illustrates much of the social ambiance that is generated by the widespread usage of a free videoconferencing tool.
***Begin Sidebar***
CU-SeeMe is available to anyone, although it only work only on IP networks. It doesn't work very well at modem speeds, though we've been amazed at what participants connected via low-bandwidth methods seem willing to put up with. Gray-scale video at one frame per second is not very impressive compared to a face-to-face meeting, but pretty exciting compared to telephone or email.
Actually, though, I think videoconferencing is most interesting when not compared to anything at all. It is not the replacement of any existing communication that is most interesting, but rather the generation of new communication. I was talking to a guy at Penn State today. He was saying how unhappy AT&T would be if it knew how much long-distance phone revenue it was losing since he has been using CU-SeeMe to maintain a long-distance romance. Yeah, except that he met her on CU-SeeMe, and there wouldn't have been any communication at all if it hadn't been for CU-SeeMe! He ended up driving nine hours to visit with her in person. So much for the idea that videoconferencing is going to reduce travel - it's going to increase it!
I actually think there is a good lesson in that little story, and it's applicable to business communication as well as social. I hope that the economic and regulatory environment develops in such a way that we simply have a lot more communication going on. Traditional providers will still come out ahead, even if they are getting much less revenue per information exchange. How's that for a speech?
***End Sidebar***
Videoconferencing might not reduce travel for personal use, but it likely will for business. In fact, that is a cornerstone for justifying its cost to management. Every business traveler costs several hundred dollars for the trip and a recurring daily cost for food, car rental, and lodging. One meeting handled through videoconferencing can save all that expense and more than pay for itself. Better yet, it can enable a face-to-face meeting that would not otherwise have occurred at all. For a team dispersed around the world, several multi-thousand dollar trips to Europe each year per team member is understandably frowned upon. The several hundred dollar one-time per-seat cost spread over several years' use is much more likely to win approval.
What You Need to Use This Book Effectively
You know how to operate your Macintosh or Windows computer. You won't find any explanations of mice, keyboards, or floppy disks here.
You are already connected to the Internet (or some other TCP/IP network) or you are ready to purchase, install, and configure the necessary hardware and software, which I discuss in Chapter 4, Hardware, and Chapter 5, Software, respectively.
That's it.
Paths Through This Book
There are several ways of traversing this book, depending on your experience and what you want to get out of it.
If you're completely new to networking, the Internet, and CU-SeeMe, then I echo the Red King's suggestion: "start at the beginning and continue until you come to the end, then stop." Chapters 1 through 6 are a step-by-step introduction and how-to guide for getting networking running on your Macintosh or Windows computer and for obtaining, installing, configuring, and using CU-SeeMe. Appendix A, Troubleshooting, contains troubleshooting assistance.
If you're already on the Internet, but you know little about CU-SeeMe, then I suggest you read Chapters 1, 2, 5, and 7, in that order. Chapter 6 is the CU-SeeMe User's Guide, which is useful for getting comfortable with the ins and outs of CU-SeeMe.
If you're already using CU-SeeMe, then you'll probably find capabilities that you didn't know CU-SeeMe had by reading Chapter 6, The User's Guide. Chapter 7, Reflectors Around the World covers some of the interesting reflectors currently open to the public.
If you already run a CU-SeeMe reflector, or you're considering doing so, you'll want to see Appendix B, the CU-SeeMe Reflector Operator's Guide. It covers reflector theory and practice from the ground up, starting with an introduction to the CU-SeeMe reflector, why you'd want or need to use one, how to properly configure and administer your reflector, and how to interoperate with other types of videoconferencing on the Internet, particularly Network Video (NV) and the Multicast Backbone (the MBONE).
Perhaps you're just evaluating Internet Videoconferencing, something that you've heard is of interest to corporate meeting planners, something that helps your employees stay in touch. Then please read Chapters 1 and 2 to get a feeling for what videoconferencing is like in general and what CU-SeeMe in particular can do.
Something for everyone, so that we can make our business connectivity more productive and our social connectivity more rewarding.
How to Get CU-SeeMe
CU-SeeMe is available for free from Cornell University at ftp://cu-seeme.cornell.edu/pub/cu-seeme. What follows is a step-by-step guide to retrieving the latest version of CU-SeeMe, as done with Anarchie, my Macintosh ftp client of choice. The same steps apply to other ftp clients for both Macintosh and Windows systems.
??? FRAN: Should be Figure 1.11 or 1.12, depending on how you renumbered. -horman
??? FRAN: Should be Figure 1.11 or 1.12, depending on how you renumbered. -horman
??? FRAN: Should be Figure 1.12 or 1.13, depending on how you renumbered. -horman
??? FRAN: Should be Figure 1.12 or 1.13, depending on how you renumbered. -horman
??? FRAN: Should be Figure 1.13 or 1.14, depending on how you renumbered. -horman
??? FRAN: Should be Figure 1.13 or 1.14, depending on how you renumbered. -horman
CU-SeeMe for Windows is found in folders beginning with PC. Select the highest-numbered - for example, PC.CU-SeeMeW0.34b5 in Figure 1.13.
??? FRAN: Should be Figure 1.14 or 1.15, depending on how you renumbered. -horman
??? FRAN: Should be Figure 1.14 or 1.15, depending on how you renumbered. -horman
Macintosh owners of the discontinued VideoSpigot card can find the necessary drivers in the folder named Spigot (see Figure 1.14).
??? FRAN: Should be Figure 1.15 or 1.16, depending on how you renumbered. -horman
??? FRAN: Should be Figure 1.15 or 1.16, depending on how you renumbered. -horman
??? FRAN: Should be Figure 1.16 or 1.17, depending on how you renumbered. -horman
??? FRAN: Should be Figure 1.16 or 1.17, depending on how you renumbered. -horman
Chapter 2, Typical CU-SeeMe Usage contains complete information on setting up and using CU-SeeMe.
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