"Gallaudet Digital Video Applications"

Gallaudet University Digital Video Applications June 27, 2003 King, Dellon, & Murray, http://academictech.gallaudet.edu/events/2003/ntid Page 1

Gallaudet University Digital Video Applications Cynthia M. King, Ph.D., Executive Director, Academic Technology

James Dellon, Manager, TV & Media Production Services Jeffrey Murray, Special Projects Producer, TV & Media Production Services Gallaudet University, 800 Florida Avenue, NE, Washington, DC 20002-3695

Paper Presented at Instructional Technology and Education of the Deaf National Technical Institute of the Deaf, Rochester, NY

June 27, 2003 http://www.rit.edu/~techsym/detail.html#F10B

SUMMARY: Gallaudet University uses digital video technologies such as streaming video and video conferencing to support online visual learning in deaf education. These applications must address the qualitative and technical requirements of sign language video and captioning, creating particular demands for broadband networks between users and institutions. ABSTRACT. Deaf education is an inherently visual learning environment. Gallaudet University's Academic Technology units are developing and supporting streaming media and video conferencing technologies to provide online course materials and applications for distance learning and institutional support. These include digital video clips to supplement classroom teaching, edited excerpts from external sources, specially produced video material highlighting cultural events, and live video conferencing between institutions and student groups for course, professional development, administrative, and student services applications. Video conferencing has been used to link students at deaf schools for joint peer-to-peer learning, as well as special applications such as career placement interviews. Online video applications are integrated with curriculum materials using online learning tools such as Blackboard. Gallaudet employs several of the popular streaming formats such as RealMedia, Windows Media and QuickTime, as well as a very high quality MPEG-2 vBrick system by for use in optimized broadband network environments. Because of the qualitative and technical requirements of sign language, high resolution and captioning are needed to ensure successful digital video applications. Bandwidth issues must be considered, and Internet 2 quality connections are preferred. While support for captioning in streaming media is improving, it is still not adequately supported in the h.320 and h.323 videoconference standards.

Gallaudet University is a four-year liberal arts university for deaf and hard-of-hearing students located in Washington, DC. Since its founding in 1864, Gallaudet has emphasized the importance of ensuring that students participate in stimulating, visually-rich, interactive learning environments. The University has been a pioneer with technologies from analog and digital captioning, to an award-winning television production “Deaf Mosaic,” to laser videodiscs, to video conferencing, to live and on-demand digital media, to a digital media library initiative. In August 2002, it also opened a new Student Academic Center (http://sac.gallaudet.edu), building on more than 10 years of classroom research and designed to provide world-class deaf-friendly interactive learning spaces, student services, and recreational facilities.

Instructional Technology and Education of the Deaf 2003 http://www.rit.edu/~techsym National Technical Institute for the Deaf Rochester, NY

In this paper, we describe some of the digital video projects and research that Gallaudet University has conducted. The paper covers video conferencing, streaming video, convergence, and a summary. Subtopics for the first two major sections include: (a) Gallaudet history, (b) conferences and high-bandwidth experiments, (c) applications, (d) video relay services and Virage webcasting

http://www.rit.edu/~techsym/detail.html

http://sac.gallaudet.edu/

Gallaudet University Digital Video Applications June 27, 2003 King, Dellon, & Murray, http://academictech.gallaudet.edu/events/2003/ntid Page 2 and publishing, (e) technical issues, and (f) resources. Screen shots from a sampling of applications can be found in the Powerpoint presentation for this paper at http://academictech.gallaudet.edu/events/2003/ntid (Paper #1 Slides). Video Conferencing The popularity of video conferencing within deaf education is not surprising. Especially for those who prefer sign language, video conferencing provides a much richer venue than text for communications with people at a distance. The two most popular formats for video conferencing today are ISDN (H.320, 1990) and IP (H.323, 1996). A new format, Session Initiation Protocol (SIP, 1999) is growing in popularity. These terms are well-known in Deaf Education. Briefly, however, ISDN uses digital phone lines, which provide reliable transmissions and have per minute charges. IP and SIP use the Internet, which provides “best effort” transmissions with no per minute charges. The quality of IP and SIP conferences can vary based on time of day and the amount of other traffic on routes used to connect two points on the Internet. IP calls on Internet2 (http://www.internet2.edu) are typically more reliable than IP calls on the commodity Internet. Within Deaf Education, ISDN is probably the most popular format, with IP increasing steadily. Gallaudet History with Video Conferencing. Table 1 includes major milestones in Gallaudet University’s video conferencing history. Pioneers and early adopters1 began experimenting with Nortel desktop systems as early as 1996. These systems were used in research projects primarily in K-12 environments with more limited use at the college level. Trials were conducted with early products like CUSeeMe, but sign language quality was unsatisfactory. Centralized support for video conferencing began in 1998, with increased support beginning in 2000, when the TV department joined Academic Technology and we received a gift from 3COM of four units (just prior to the sale of their video conferencing systems to Polycom). In the first years of centralized support, departments had to pay the ISDN charges if they used ISDN. By the end of 2001, we were able to centralize costs for the ISDN lines as well. To improve the quality of IP video, Gallaudet sought and received a National Science Foundation grant for Internet2 in Sept 2001 (http://academic.gallaudet.edu/internet2). The connection was installed in March 2002, with availability in all locations on campus. Table 1. Milestones in Gallaudet University Video Conferencing History 2002 Student Academic Center IP, ISDN, Internet2 (http://academic.gallaudet.edu/internet2) 2001 First Credit Course Offered Completely via Video Conference

(Business course with an instructor in Texas and the students at Gallaudet) 2000 Television and Media Production Services IP, ISDN (3Com Gift) 1999 Project Achieve (Martin) ISDN 1998 Learning Technology IP, ISDN 1996 Project SOAR (Snyder) ISDN 1995 GU Kellogg Conference Center (GUKCC) ISDN


1 Pioneers are involved in the development of new innovations. Early adopters are among the first to use such innovations.

http://academictech.gallaudet.edu/events/2003/ntid

http://www.internet2.edu/

http://academic.gallaudet.edu/internet2

http://academic.gallaudet.edu/internet2



Currently, Gallaudet has a number of origination points for high quality video conferencing. The Student Academic Center (SAC, http://sac.gallaudet.edu) has a dedicated distance learning classroom, seating 20 plus observers, equipped with a Polycom VS4000, 3 wall-mounted cameras, proximity microphones, and video projectors. All other classrooms and several meeting spaces in SAC are equipped with patchable ISDN lines to support video conference events using Polycom units on a wheeled TV cart. A conference room located in the Merrill Learning Center is often used for small classes and meetings. A classroom in the Model Secondary School for the Deaf (MSSD) with video conferencing equipment is used frequently for student collaborations such as Project JASON (http://www.jason.org). For very large events, the Elstad Auditorium, which seats more than 700, and the GUKCC auditorium, which seats 275, can be set up for video conferencing. Multi-point conferences, up to four sites, can be handled with the VS4000 and other Polycom units. For larger numbers of sites or conferences where there is a need to bridge across protocols, Gallaudet uses the Internet2 Commons services (http://commons.internet2.edu). Additional units in other locations are being planned. For IP (H.323) video conferences, Polycom units can be delivered anywhere there is a network connection. Gallaudet University. IP video conferences with Polycom Via Video, video phones, and desktop webcams are also popular. Video Conferencing Conferences. Beginning in 1999, Gallaudet began co-hosting a series of conferences on video conferencing. The first was held at the Texas School for the Deaf in Austin, Texas. The next two were held at Gallaudet University (2000, 2002), with the fourth planned for April 11-13, 2004 at Gallaudet as well. The announcement and call for papers are now available on the web site (http://academic.gallaudet.edu/videoconf2004). In 2002, the focus of the conferences expanded to include other video technologies in addition to video conferencing. Video Conferencing Applications. Uses of video conferencing are as diverse as the populations we serve. Video conferencing is used for distance learning—sometimes just for a single class session, sometimes as the primary means of instruction, sometimes with remote students and sometimes with remote instructors. Other uses include: admissions, career and other types of interviews, student collaborations, instructor collaborations, outreach and other meetings, and supervision of internships. Some examples of video conferencing projects within the past academic year include:

A Ph.D. candidate attended a weekly lecture series nearly 100 miles away via video conferencing over the Internet 2 connection. This not only saved her four hours of travel time each week, but allowed her to use on-campus interpreters, saving interpreter travel-time charges and providing a higher quality interpreting than might have been found at the remote site. A popular former faculty member, now teaching in Texas, taught a semester-long seminar using video conferencing. The students at Gallaudet connected to her new home institution each week and enjoyed a lively two-hour class via video conferencing. Students were taught how to set-up and operate the video conferencing equipment, and required little, if any, staff support after the initial training period.

http://sac.gallaudet.edu/

http://www.jason.org/

http://commons.internet2.edu/

http://academic.gallaudet.edu/videoconf2004



The Gallaudet Honors Program uses video conferencing to interview students who have applied for the program. This allows the faculty to meet and evaluate more students earlier, allowing for acceptance into the program prior to arrival at Gallaudet. The Admissions Office also uses video conferencing. The Gallaudet and NTID student body governments meet on a regular basis to discuss mutual interests and collaborative projects. This collaboration is scheduled to continue in the next academic year. An accreditation team, evaluating Gallaudet’s programs preparing school personnel, interviewed supervising teachers at deaf schools in Massachusetts and Pennsylvania to obtain feedback about the training and support offered to Gallaudet students doing practica at their schools. The President’s Office uses video conferencing as an outreach tool to deaf schools and civic and government organizations. For example, President I. King Jordan used video conferencing to appear as the featured speaker at the Gallaudet/Japanese Alumni Association’s annual Gala in Tokyo. On another occasion, Dr. Glenn Anderson, Chairman of the Gallaudet Board of Trustees, addressed a Washington meeting of Gallaudet’s Board of Associates from his office at the University of Arkansas. Graduating students and potential employers utilize the technology to conduct job interviews without incurring the cost and inconvenience of traveling. Students are also interviewed for internships, and some supervision of internships is done remotely through video conferencing.

Video Relay Services (VRS). Gallaudet University participated in special trials with several VRS vendors as they developed their services. We also worked with two vendors when it was discovered that webcams with firewire connections were not compatible with VRS. At the current time, community members select from the various services available (see resources below). Web cams are available in all public computer labs, and video phones have been placed in strategic locations for community use. Recently, the Gallaudet Interpreting Service (GIS) announced a relationship with Sorenson Video (http://www.sorenson.com/content.php?pageID=35&id=40&nav=7). Gallaudet has also used remote captioning and remote interpreting services, as well as experimenting with these technologies ourselves. Video Conferencing Technical Issues. As many know, the most challenging technical issue for video conferencing is bandwidth. Most video conferencing applications in deaf education require at least 384Kbps for comprehensible sign language. For both ISDN and IP, 384Kbps is still sometimes jittery or unclear, especially for fingerspelling. Gallaudet’s experiences with IP video conferencing indicate that 768Kbps is the preferred speed—at least if both ends have Internet2 connections. Interestingly, even when both ends have Internet2 and systems capable of 2 or 3 Mbps (e.g., 2,000 to 3,000Kbps), performance and comprehension often degrade above 768Kbps because the higher data rate puts stresses on the network, resulting in more dropped packets. Our observations with SIP video conferencing to date indicate that such systems will need improvement before they are useful for sign language communications—again because of the

http://www.sorenson.com/content.php?pageID=35&id=40&nav=7



limited frame rate and jittery video. We found a similar result with video phones, except for the Sorenson video phone with Envision software, which has been optimized for sign language movements. We have seen a Sorenson video phone work well at 460Kbps over the campus LAN. Captioning support remains a significant hurdle for video conferencing systems in terms of accessibility. In its higher-end models, Polycom provides a web tool for adding titles and typed text to video conferencing displays, but the tool does not meet the demands for full access to speech, which typically runs 200 to 250 words per minute while typing speeds are typically 50 to 100 words per minute. Unfortunately, a grant proposal (http://academictech.gallaudet.edu/grants/FIPSE2002) by Gallaudet University and The University of Tennessee to address this problem was not funded by FIPSE. Efforts are needed to integrate standard captioning tools (stenography, computer-assisted note taking, and speech recognition) with existing video conferencing systems. Video Conferencing Resources. Two valuable resources for anyone interested in video conferencing are VIDE (Video Development Initiative, http://www.vide.net) and the Video Conferencing Cookbook (http://www.vide.gatech.edu/cookbook). Judy Harkins provides a useful resource on firewall solutions at http://tap.gallaudet.edu/videochat/videofirewall.htm. K-20 schools interested in the superior quality of Internet2 video conferencing can find more information about joining I2 at http://k20.internet2.edu. A detailed history of the protocols for video conferencing is available at http://myhome.hanafos.com/~soonjp/vchx.html. Video relay services used frequently at Gallaudet, in alphabetical order, are: AT &T (http://www.relaycall.com/vrs), CSD and Sprint (http://usavrs.com), Hands On (http://hovrs.com), MCI IP-Relay (http://www.ip-relay.com), and Sorenson (http://www.sorensonvrs.com). Streaming Video The term, streaming video, to describe this next section of the paper is not technically precise, but it is the term most commonly used and understood. Streaming is actually a delivery mechanism (contrasting with download, progressive download, and offline). For web-based video, streaming is the most common delivery method because users do not have to wait for the entire video to download before playing. In this section, we discuss desktop digital video applications with video in formats such as Windows Media, Real Media, QuickTime, MPEG, and Motion JPEG. Digital video formats such as mini-DV, DVC-Pro, and D2 are not discussed. Gallaudet History with Streaming Video. Gallaudet has been involved with digital video since the first desktop video formats were available in 1991. Early adopters began experimenting with new formats virtually from the moment the formats were available. Often, they were involved in beta or pre-public beta tests. In 1995, the first author of this paper, along with Doug Short, created a proprietary method for captioning digital video files, based on their earlier work (1993) with laserdiscs and Short’s earlier work (1990-1992) with laserdiscs, MIDI, and other digital audio files. Table 2 includes major milestones in Gallaudet’s streaming video history.

http://academictech.gallaudet.edu/grants/FIPSE2002

http://www.vide.net/

http://www.vide.gatech.edu/cookbook

http://tap.gallaudet.edu/videochat/videofirewall.htm

http://k20.internet2.edu/

http://myhome.hanafos.com/~soonjp/vchx.html

http://www.relaycall.com/vrs

http://usavrs.com/

http://hovrs.com/

http://www.ip-relay.com/

http://www.sorensonvrs.com/



Table 2. Milestones in Gallaudet University Streaming Video History 2003 Virage Webcasting and Video Publishing System,

New Policy for Rolling Call for Video Production Projects 2002 vBrick Network Video Distribution, Motion JPEG Experiments, Internet2,

Video-Enhanced Learning Projects (n=29); Updated CPC Captioning Software 2001 First Call for No-Cost Video Production (n=7)

(previously departments initiated requests and paid for services) 2000 First Commencement Live Webcast (Gallaudet in-house captioning method) 1998 Work on captioning standards SMIL and SAMI 1996 Projects with Streaming Video begin 1995 Captioning Research 1991 Projects with Desktop Video begin

In the early years, departments typically conducted their own projects or sought support from Television (TV) and Learning Technology (LT). In 2001, the new Academic Technology (encompassing both TV and LT from July 2000) began offering centralized media production services, based on calls for projects, at no cost for curriculum-related projects. Three calls for projects resulted in almost 50 projects, of which 36 were approved. In August 2003, we will change from twice-yearly calls for projects to a rolling call for projects that can be proposed at any time during the year. Since 2000, four University commencement ceremonies have been streamed live, enabling family and friends of the graduates who cannot attend to participate on that special day. While many institutions provide similar services, it was necessary for us to develop a method of adding live captions to a live-streamed event, something that was not then supported by either Windows Media or Real Media encoding standards. We used a captioning method developed in-house for three years. In 2003, Windows Media included a new feature for live captioning, which we used, but found there were access issues for Macintosh users and needs for some Windows users to upgrade their media players. Because of the high network demands of a live event, outside content distribution networks were contracted to host the streams to avoid unduly stressing the University’s network. High-Bandwidth Experiments. Gallaudet University was fortunate to be one of two institutions to receive high-bandwidth MPEG2 video appliances on loan from vBrick (http://www.vbrick.com) and Internet2 in June 2002 (http://academictech.gallaudet.edu/grants/vBrick2002). We used these devices, which encode video at data rates in the 5 to 10Mbps range, for distributing video, including line 21 closed captioning data, across campus. We also conducted trial video conferences between two vBricks. Quality was exceptional. Using multicast on campus, the impact on the network was manageable, although there were some problems with older network printers not excluding multicast traffic. We were unable to conduct tests with off-campus partners because the devices require multicast at that time and Gallaudet did not enable off-campus multicast until July 2003. The devices were returned to Internet2 in June 2003. We hope to purchase our own vBricks, since they are so useful in campus video distribution projects.

http://www.vbrick.com/

http://academictech.gallaudet.edu/grants/vBrick2002



Gallaudet also collaborated with The University of Tennessee and other Internet2 partners in tests with the Delco Motion JPEG video devices (http://bmrc.berkeley.edu/~delco/rtptv), which can be used for video distribution and video conferencing as well. Using these systems, video was streamed across Internet2 at 16Mbps. Again, quality was exceptional. The Delco box, however, requires substantial technical maintenance, and once appliance-level devices such as vBrick were available, we ended our experiments with the Delco box. Streaming Video Applications. Streaming video is used for many different purposes at Gallaudet University. No only does Academic Technology provide centralized services for video production, captioning, digitizing, streaming, and associated web development, many other units on campus and the students create their own streaming video. The new Student Academic Center has six video editing rooms that are used for creating, editing, and producing video products such as DVDs, CD-ROMs, web sites, and offline videotapes. In 2001, Academic Technology began working with the English Department Journalism program to create a web site with streaming video of six interviews with high profile working journalists (http://depts.gallaudet.edu/journalism/video). The interviews were taped, edited, digitized, and captioned by Television and Media Production Services. Web development was led by Learning Technology. We decided to digitize the 90 video clips in multiple formats (Real, Windows Media, and Quicktime) and multiple data rates (56K, 160K, and 300K). Three versions of caption data files also had to be created for the three video formats. We did this so we could evaluate the formats and data rates. The results led us to a decision to record future videos at 225K-300K in a single format only. The higher data rates were chosen because they provide the best access to fingerspelling and sign language. The 56K data rate is acceptable for talking heads, but typically not for sign language. As explained later, we provide offline access to files for people with phone modems. The video format for subsequent projects has varied, related to factors such as user choice and the functionality of the various media players at the time of development. Streaming video projects supported through Academic Technology fall into four main categories: curriculum projects, grant-supported projects, institutional projects, and cultural projects. Examples are discussed next. Screen shots from the project can be found in the Powerpoint presentation for this paper, available at http://academictech.gallaudet.edu/events/2003/ntid (Paper #1).

Curriculum Projects. Video is used in the DST795 course, American Deaf Culture, taught to remote students, to provide them access, in ASL, to instructor presentations and cherished historical videos such as George Veditz’s 1913 speech on the preservation of sign language. Video case studies are used in the Social Work field experience courses to provide them opportunities to see and critique case studies. Students access the videos (which are stored on a separate streaming server) and associated assignments from http://my.gallaudet.edu. These course materials are available only to students taking the courses. Grant-Supported Projects. Academic Technology’s Television and Media Production Services worked with Ron Sutcliffe and Jane Norman on their grant called Signs of Success. Profiles of and interviews with ten successful Deaf business leaders were created on the website, http://signsofsuccess.gallaudet.edu. The site is used in Business courses for Gallaudet students and available for anyone to enjoy.

http://bmrc.berkeley.edu/~delco/rtptv

http://depts.gallaudet.edu/journalism/video

http://academictech.gallaudet.edu/events/2003/ntid

http://my.gallaudet.edu/

http://signsofsuccess.gallaudet.edu/



Institutional Projects. A video for the February 2002 Unite for Gallaudet Gala was produced to commemorate Gallaudet’s successful capital campaign, a fund-raising effort that raised more than $39.9 million to support scholarships, programs, and the new Student Academic Center. The video won the 2002 CASE (Council for Advancement and Support of Education) Gold Medal and is available on the Gallaudet Development Office’s web site (http://support.gallaudet.edu/mediacenter/videoclips). Cultural Projects. In July, 2002, Gallaudet was host to DeafWay II, an international conference and festival that attracted more than 10,000 participants. To help share the week-long experience, Television and Media Production Services produced a daily video anthology (5 to 8 minutes of highlights from the previous day’s events) that were streamed over the web. These clips (http://www.deafway.org/videophotogallery) attracted thousands of “hits” from around the world during Deaf Way II and provide a strong testament to the richness and diversity of deaf culture. An expanded version of the DeafWay II Video Anthology is now being adapted into a DVD that will be available shortly. In addition, more than 300 scholarly and cultural presentations were recorded and may ultimately be digitized and indexed for research purposes.

Virage Webcasting and Video Publishing. For several years, Gallaudet searched for a digital video library product that would allow us to automate some of the production of digital video, support better live webcasts, and allow for annotation of video assets for easier searching and organization. After waiting for the products to mature, we selected Virage’s webcasting and video publishing (http://ww.virage.com) in April 2003. For live webcasts, the system supports the streaming of video in multiple formats with synchronized slides or broadcasting of the presenter’s desktop for software demonstrations. Interactivity features include polls, questions and answers, and links to related documents. Following a live webcast, an archive is available within two to three minutes (contrasting with most webcasting systems, which require overnight or a few days for post-production and posting to a web site). For video publishing (creation of video not originally broadcast live), Virage offers a template language for customizing web sites to access collections of videos as well as automated capture of captioning data, scene changes, speech recognition, and other features. During the presentation, we will demonstrate the features using Julia Child’s web site (http://www.pbs.org/juliachild). Virage also provides a method for packaging a webcast and video for offline viewing on a DVD, CD-ROM or other media. This feature will reduce some of the work associated with producing offline video, but we expect to continue other methods for producing offline video as well. DVDs such as “Gallaudet Alumni: Their Stories” are created with traditional DVD authoring tools to provide interactivity and wider distribution than that available with streaming video. CD-ROMs and analog videotapes are also produced for different audiences and needs. Streaming Video Technical Issues. Perhaps the most challenging technical issue for streaming video is the rapidly changing media players and servers. Each project involves extensive testing to check for compatibility with older versions of media players, web browsers, and operating systems. For example, the 2003 Commencement was webcast with Windows Media 9 because of its new

http://support.gallaudet.edu/mediacenter/videoclips

http://www.deafway.org/videophotogallery

http://ww.virage.com/

http://www.pbs.org/juliachild



support for live captioning. However, the video and captions would not display on Apple Macs. We also had to limit access to Windows Media Players 7 and above. An equally-important technical challenge is the complexities of captioning for streaming video. Although two of formats (Real, Quicktime) use SMIL (http://www.w3.org/AudioVideo), they format the caption files differently, and Windows Media uses SAMI or HTML+Time (http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnacc/html/atg_samiarticle.asp). The Timed Text working group of the World Wide Web Consortium has recently published a document with use cases and requirements for development of a standard method for captioning (http://www.w3.org/AudioVideo/TT). As streaming video becomes more common, issues related to bandwidth become more important. For example, during Gallaudet Commencement 2003, 233 individuals were watching the video stream at the same time. Overall, there were 4,676 different “hits,” with the average person watching the video for about nine minutes. To reduce the impact on the Gallaudet network (which has one 45Mbps connection to the commodity Internet and one 45Mbps connection to Internet2), an outside content distribution network (CDN) is used for major events like this. Even with the CDN, Internet traffic from and to Gallaudet increased to approximately 22Mbps during Commencement. For future events, we will provide separate external and internal video streams. Streaming Video Resources. The Video Development Initiative (http://www.vide.net) is currently preparing a Streaming Video Cookbook, parallel to the Video Conferencing Cookbook. The second author of this paper is contributing to that product. The authoritative resource on web accessibility issues is the Worldwide Web Consortium (W3C) Web Accessibility Initiative (http://www.w3.org/wai). Information on streaming video accessibility is at http://www.w3.org/AudioVideo. Other useful resources include WGBH’s National Center for Accessible Media (http://ncam.wgbh.org) and Utah State University’s WebAim “Web Accessibility in Mind” (http://webaim.org). Jamie Berke maintains a website on captioning that provides extensive information about various captioning software and hardware (http://www.captions.org). Convergence Convergence means “coming together or bringing closer.” In the digital video world, convergence is happening rapidly between video conferencing and streaming video and between live and on demand. Video conferencing systems such as Polycom support webcasting of the conference to people via the web and recording for on demand viewing after the conference. Video appliances such as vBrick can be used for video conferencing or streaming video. Systems such as Virage convert live webcasts into on demand archives in minutes. At Gallaudet, we carefully match the digital video format and tools to the audience and purposes for which the video is intended. For high interactivity, video conferencing is best for live events and offline DVDs for on demand events. For moderate interactivity for more lecture-style events, Virage is best for live and on demand events. For low interactivity, we typically choose a streaming video format. Interactivity can also be added to streaming video format through the authoring tools for each format or through presentation of the video in concert with activities presented through a

http://www.w3.org/AudioVideo

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnacc/html/atg_samiarticle.asp

http://www.w3.org/AudioVideo/TT

http://www.vide.net/

http://www.w3.org/wai

http://www.w3.org/AudioVideo

http://ncam.wgbh.org/

http://webaim.org/

http://www.captions.org/



course management system or other web authoring tools. For users of phone modems, hybrid systems (web activities plus video on the computer’s local CD-ROM or DVD) or offline videos are developed. Summary Gallaudet University has a long and proud history of designing and delivering stimulating, visually-rich, interactive learning environments. Digital video applications such as those discussed in this paper provide opportunities to expand upon the rich face-to-face instruction that is a vital part of our culture. For deaf and hard of hearing students, the technology provides needed accessibility solutions and new tools for expressing themselves. Because of the qualitative and technical requirements of sign language, high resolution and captioning are needed to ensure successful digital video applications. High resolution videos can impact network performance, and so bandwidth issues must be considered. Solutions should be selected to meet the goals and the interactivity and connectivity needs of the audience. Although support for captioning in streaming media is improving, it is still not adequately supported in H.320 and H.323 video conferencing systems.

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"Gallaudet Digital Video Applications"