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Monson H. Hayes, Fellow IEEE, and Michael Mayercik, Student Member IEEE
Abstract - The Georgia Institute of Technology in Atlanta is in a unique position of having a campus located across the Atlantic in the heart of the Lorraine region of France in the city of Metz. With Masters Degree programs in Electrical and Mechanical Engineering, Georgia Tech Lorraine (GTL) offers more courses than can be staffed by resident faculty. Therefore, GTL must offer a number of courses in EE, ME, and Mathematics by videotaping courses that are taught by faculty at the Georgia Tech campus in Atlanta. Delivering courses by videotape, however, is relatively expensive, introduces a two week delay between the two sections of the courses, and is not the most convenient method of course delivery for the student. In this paper, we describe the techniques that we have used in delivering graduate level EE courses in near real-time across six time zones using the Internet.
Cost: In addition to the normal costs associated with the taping of lectures, offering video courses requires that videotapes be shipped by express mail from Atlanta to Metz. For a class that meets for one hour three times a week, this involves the shipment of three VHS tapes per course per week. Offering on the average of five courses per quarter, this amounts to fifteen video cassettes per week. Then, at the end of the ten week quarter, the 150 videotapes are shipped back to Atlanta. In addition to the shipment of videocassettes, it is necessary to express mail or fax exams and homework between the instructor in Atlanta and the students in France.
Delay: With the shipment of video tapes each week from Atlanta to Metz, there is a inherent delay between the lectures being given to students in Atlanta and the lectures being viewed by students in Metz. With a Friday shipment, the tapes typically arrive in Metz the following Monday or Tuesday. Since these tapes contain the previous week's lectures, this results in a minimum one week lag between the two sections of the course. In addition, however, allowing for a day to log and file the tapes, viewing typically does not begin until Wednesday. With French plus U.S. holidays to consider, and with the anticipation of occasional delays in the arrival of the tapes, GTL students are allowed to be as much as two weeks behind the schedule of the Atlanta section. For example, a lecture given to a class in Atlanta on Monday, February 1, may be viewed by GTL students as late as Monday, February 15 without falling behind.Although there may never be an acceptable substitute for an instructor teaching a course to a live audience, there are now viable alternatives to delivering courses remotely by videotape. To alleviate some of the problems associated with offering courses by video at GTL, we have been experimenting with the delivery of courses using streaming audio and video from Georgia Tech in Atlanta to Georgia Tech Lorraine. Although the method of delivery continues to evolve as new tools and techniques become available, in the following sections, we describe the approaches that we have used, give a "snapshot" of our course materials, and describe our students' reactions to an Internet-based course.
Student Inconvenience: Taking a course by video creates some problems and inconveniences for the student. First, since only one tape is shipped, it may be difficult to allow students to view the tapes at different times. To make matters even more difficult there is a difference in format between video tapes in the US (NTSC) and in Europe (PAL/SECAM). This makes the duplication of tapes difficult and costly once they arrive in Europe. Office hours are also a problem with taped classes and, with a six hour time delay, getting questions answered and receiving instructor feedback is difficult, at best.
Instructor Inconvenience: In addition to being inconvenient to GTL students, a delayed video section is also inconvenient for the instructor since he/she must answer questions, grade homework, write and grade exams, and distribute solutions to assignments and quizzes at two different times that are spaced two weeks apart.
A. Distance Learning with Streaming Audio
Our first experiment with using the Internet to deliver courses across the Atlantic took place in the Fall Quarter of 1997 in the offering of a graduate level course in Neural Networks. This course was offered to students live at GTL, and delivered via the Internet to students in Atlanta. With the Atlanta section being six hours behind the section in France, it was possible to have students at each location viewing the lecture on the same day. The way that this course was delivered is as follows.
Another approach that was used on occasion, which was less time-intensive, was to write the slides on paper, scan them into the computer as a GIF file, and then import then into PowerPoint slides.
Lecture Presentation: Having a set of PowerPoint slides, the presentation of the course to the live audience was straightforward. The PowerPoint slide show was projected onto a screen using an LCD projector, and the audio portion of the lecture recorded, in real-time, using a Real Audio encoder.
Post-Lecture Production: After each lecture, assuming the timings for each slide have been recorded either electronically or manually, these timings must be merged with the Real Media video file. This is a simple procedure currently consisting of two steps. First, the creation of a text file in which each line of text contains a start and stop time as well as the appropriate slide to show during that portion of the video. Second, the text file and the Real Media video file are merged together using a program that comes free of charge from Real Networks. Given the lecture format, there was also some work involved in creating the html files that link together and index the lecture. Since most of this work is repeated for each lecture, once the format of the WebPages has been standardized, a simple program could be written to automate the generation of the html code that delivers the desired lecture. As our method of delivery had not been standardized and was constantly being modified and improved, full automation of the process of posting courses to the web was not undertaken immediately. This entire process of producing real media files takes approximately two hours for each lecture.
Delivery From GTL to Atlanta: After having generated a RealMedia file, the last step in the process was to transmit the course materials from GTL to Atlanta. These materials included postscript copies of the slides, real audio files (.RA and .RAM), and updates to the course Homepage. The postscript files along with the HTML files were sent electronically by ftp to the Web server in Atlanta. The real audio files, on the other hand, were sent by ftp to the Real Audio Server that was operated through the Distance Learning Center of the Georgia Institute of Technology.
From the student feedback that was received, it became clear that this mode of course delivery has been accepted with enthusiasm. When the students were asked to compare the Internet version of the video class to those using videotapes, their reactions were consistently in favor of the new technology. The main advantage over videotapes that they all agreed upon was the virtually instantaneous delivery of the lecture material over the Internet. Normally, students in France have to wait two weeks or more for the lecture materials including tests and homework to arrive from across the Atlantic, whereas with this new technique of course delivery, the student can have all materials delivered to him or her at no cost on the same day that the lecture is being given live in Atlanta.
Although a Web-based course that is delivered on the Web with streaming audio allows for near real-time delivery of courses across the Atlantic, this mode of delivery does not give the student any sense of "being in the classroom." What is needed to help alleviate this problem is streaming video that allows the student to "participate" in the class, by being able to "see" the instructor, to observe the instructor's gestures and expressions, and to allow him or her to follow more closely the material that is being presented on a slide. In the following section, we describe our experiments in offering a course at Georgia Tech in Atlanta, with remote delivery of the course to a section at GTL using streaming audio and video.
B. Distance Learning with Streaming Audio and Video
In the Winter Quarter of 1998, we offered a graduate level course in Statistical Digital Signal Processing to a section of students in Atlanta. Similar to the streaming audio course that was delivered from GTL to Atlanta in the Fall of 1997, this course was delivered to a section of GTL students via the Internet using streaming audio and video. The Real Video Server was installed on a Windows-NT server located at GTL. For this course, the PowerPoint mode of delivery was dropped in favor of using the seminar macros for producing slides in LaTeX. Postscript and Adobe PDF versions of the slides were prepared, two to a page, and made available on the web to the student, and full page copies of the slides were printed and used to present the lecture material to the live section in Atlanta. These slides were captured by an overhead camera, and projected onto a set of monitors that were distributed throughout the classroom. The video was also recorded and used to generate the streaming video for the remote section.
After electronically transmitting all of the files for a given lecture from Atlanta to GTL, the student was able to access postscript and PDF versions of the lecture slides, which he or she could print out for note taking, and could view a streaming video presentation of the lecture that was linked and synchronized to the slides. Thus, by clicking on an icon for "Viewing the Lecture," a Web page consisting of three frames was displayed on the computer. In the upper left-hand corner, a Real Video console appears, which delivers streaming audio and video to the student, and contains a video control panel that allows the student to fast forward, reverse, or pause the lecture. Below the Real Video Player is an index of the slides that the viewer may click on to have immediate access to that portion of the lecture. Finally, in the third frame, which occupies the majority of the screen, is a GIF version of the current slide.
In putting together a Real Video course, the following two questions needed to be addressed.
Our philosophy has been that, over the long term, we plan to offer real-time streaming video courses over the Internet. Therefore, although the bandwidth is expected to increase over the next few years, we have selected 28.8 kb/s as the target bit rate. At this rate, the Real Video encoder assumes that 20 kb/s can be used for audio and video. Although we have not yet conducted any surveys, or performed any subjective testing, it appears that the best allocation of 20 kb/s is to use 15 kb/s for video and 5 kb/s for audio. Obviously, with only 15 kb/s, the video quality is poor. However, even with low-quality video, it is possible for the instructor to transmit a fair amount of information to the student. For example, the instructor is able to gesture, point to equations, and underline key points on a slide. As a result, the student is able to feel a bit closer to the live classroom.
For a 50 minute lecture, audio and video delivered at the rate of 20
kb/s requires only 7.5 MB. Therefore, an entire ten week, three hour
quarter course can be saved using only 225 MB (audio and video only).
Postscript and PDF files of the slides without too many embedded JPEG or
GIF images requires less than 0.5 MB per lecture.
In our course, we have considered two video formats. The first is a "Talking Heads" production, in which a head and shoulders video of the instructor is displayed in the real video player, as shown in the image below. The slides are displayed in sequence alongside the video.
The second mode is to display a video of the slide, which may include the instructor's hand or pen pointing to an equation or underlining a key point on the slide, as illustrated in the image below. At the same time, a small head and shoulders video of the instructor is occasionally inserted into an empty region of the slide. In addition, to break the pattern of showing only a video of the slides, when there is little or no action on the slide, the video of the slide is replaced with a full-screen head and shoulders video of the instructor, as shown in the clip above.
What appears to be preferable is the second mode. Although the text on the slides is not legible, the information that is transmitted through gestures such as pointing is extremely valuable. In addition, the ability to insert a small talking heads image imparts some realism to the lecture.C. Beyond Distance Learning
Our primary objective in developing Web-based offerings of courses at Georgia Tech Lorraine was to facilitate the delivery of courses that originate in Atlanta by cutting costs, and reducing the two week delay in course delivery down to only a few hours. However, as this mode of delivery becomes easier, more widespread, and more readily accepted, there will be some additional benefits to this method of course delivery.
Archival: The first benefit is the ability to archive a complete course on disk or CD-ROM. This archived course could then be used by the instructor to modify and improve future offerings of the course, or it could be used as reference material to assist other instructors in teaching the course. The archive could also be used to offer the course in later quarters without having to arrange for a faculty member to physically deliver the lectures. This might be particularly attractive for low enrollment classes or seminars.
Scheduled Absences:. The second advantage with the production of a Web-based course is that it affords the instructor the ability to "pre-record" a class in order to accommodate a scheduled absence for a meeting, such as a conference or a review panel. For students taking the course locally, these pre-recorded lectures may be viewed on the Web, as done by the distance learning students.
Courses Bundled with Books on CD-ROM: With publishing companies beginning to produce books on CD-ROM, having an integrated set of lectures that offer hyperlinks to the text and that probe the student's grasp of material by asking questions opens up a whole new set of interesting possibilities.
Second, the Internet material should give the student a sense of being in the classroom to whatever extent that is possible. The four key categories of information that we provided in the homepage are listed below with links to some examples that were a part of the Internet classroom.
Assignments. In this page, we provided the student with an up-to-date listing of all assignments, with the due dates clearly indicated. It is expected that future versions of these courses will allow for homework to be submitted, graded, and returned over the Internet. We are currently in the process of looking at several methods of doing this.
Internet help. This page was designed to assist the student in finding all of the software that is necessary to view the course from a computer at home, and to provide instructions on how to install and use the software. Currently, the only software that is required is an Internet browser, a Real Video Player, and either Ghostview or Acroread for printing copies of the lecture slides.
Calendar. A calendar provided the student with a current calendar of exam dates, lecture titles, and homework assignments.
Lectures. This was the key page for the course. It provided links to Postscript and Adobe PDF versions of the lecture material, and links to the Real Video Server that enable the student to receive steaming video of each lecture.
By far, the biggest problem that we encountered in offering a streaming video course in Electrical Engineering at GTL was the lack of easy-to-use tools for producing high-quality Internet-based course materials, and the inability to easily generate Greek letters, equations, plots, and figures in HTML. Although there are some tools, such as LaTeX2HTML, that will produce an HTML file from a LaTeX document, these programs do not provide the ideal solution.
The other problems that we encountered occasionally were related to students having difficulties accessing course materials from home. In some cases, these problems were due to the student not having all of the software properly installed. In other cases, they stemmed from network congestion or server problems. It is clear that for any large distance learning program to be successful in the future, it will be necessary to provide students with 24/7 support.
B. Future Enhancements
The techniques that are available for delivering Web-based courses are changing rapidly. As new tools become available, new approaches will be considered. Over the six months that we have been developing and offering courses on the Web, we have observed a rapidly changing market. Given our belief that the Internet will be a valuable resource in the remote delivery of educational material and classes in the very near future, we are in the process of incorporating several enhancements to our next GTL Web-based course. These enhancements include the following.
Given the size and scope of the project, a considerable amount of thought was given to how it should be designed, produced, and delivered. Unlike many other on-line courses, we chose to structure the course using lecture "modules" that are anywhere from five to fifteen minutes in duration. There were several reasons for this. The first is that short modules are better suited to the effective attention span of the student. The second reason is that it is much easier for an instructor to prepare, produce, edit, and modify short lecture modules compared to a full hour lecture. The third is that is that it is much easier for modules to be "repackaged" into short courses, and shared with other Internet-based courses.
As previously mentioned, a tremendous investment in start time is required to design and develop a course for Internet delivery. By far the most significant investment in time is in content preparation. However, once the course content has been created, to produce a streaming media course, a large amount of tedious work is required. This work includes the extraction of timing information for slide synchronization, the writing of SMIL files that orchestrate the streaming media production, and the design of the HTML pages and links. Therefore, early in 1999, we decided to write a scripting program that would automate the recording of timing information, and generate all of the necessary streaming media files. The result was a set of simple tools, written in Perl that reduced the production time from a couple of hours to a few minutes. The next step was to develop a user-friendly front-end that would allow an instructor to publish his or her content for Internet delivery without having to use command line instructions. At the same time, some useful generalizations and extensions to the original program were added, including
FIGURE 1: The user interface.
All that the instructor needs to provide as input to the program are
postscript files containing the slides, or individual images of the slides
in GIF, JPEG or PNG format. Then, with a video camera focused on the instructor,
a lecture module is captured to disk while progressing through the slideshow.
Once the video has been encoded, the tool is then ready to automatically
generate all of the necessary streaming media files. An example illustrating
one of the presentation formats that this program generates is shown in
Figure 2. The presentation format is flexible, allowing the user to change
backgrounds, the elements included, and the layout. This allows the creation
of lectures including only audio, or with additional information in the
windows around the slide, thus allowing the instructor to tailor the presentation
to his teaching style or the learning style of his students. Any of the
media windows can be made hot with links to supplementary material that
change as the presentation progresses. This allows a single window to be
used as a "Supplementary Information" window, with extra readings or links
that correspond to the portion of the lecture currently being viewed. The
primary advantages of these tools are simplicity and portability. Although
many of our Internet courses are filmed in a small studio, instructors
can capture lectures in their own office, at home, or in the classroom.
This set of tools is currently available, free of charge, from the website
In discussing on-line courses, there are two approaches that one may consider. The first is to "capture" the classroom during a live lecture, and place it on the Internet for distance learning students. The second is to produce lectures or lecture modules outside of class in a studio or office, and produce an Internet version of a course. In the second case, the inFusion tools allow for both the capture and the placement of the audio, video, and HTML pages on the Internet. In the first case, inFusion could be used to capture all of the timing information for synchronization, and the production of the necessary multimedia files could be done outside of class at a later time.
FIGURE 2: A screen shot of a streaming media course produced using our development tools.
Having created a simple set of tools to bring synchronized and indexed audio and video easily onto the Internet, the next set of issues that should be addressed center around how to make effective course content that will enhance the learning environment for the student. Another issue is how to create a set of tools for designing courses that will allow for indexing and searching without and across courses, assessment, evaluation, and course flow that is dependent upon the student's learning style.
[2[ M.H. Hayes and L.D. Harvel, "Distance learning into the 21st century", Proc. ASEE Workshop, Charlotte, NC, June 1999.
 K. Betts, "Why do faculty participate in distance education?", Horizon Web Magazine, Oct. 1998.
 M.H. Hayes and M. Jamrozid, "Internet distance learning - The problems, the pitfalls, and the future", Proc. of IEEE Workshop on Multimedia Signal Processing, pp. 569-574, Copenhagen, Denmark, Sept. 1999.
 G. Abowd, "Classroom 2000: An experiment with the instrumentation of a living educational environment", IBM Systems Journal, vol. 38, Oct. 1999.
 J. Brotherton, J. Bhalodia, and G. Abowd, "Automated capture, integration, and visualization of multiple media streams", Proc. of IEEE Conf. on Multimedia and Computing Systems, pp. 54-63, July 1998.
 World Wibe Web Consortium (WC3) Recommendation: Synchronized Mulimedia Integration Language (SMIL) 1.0 Specification. http://www.w3.org/AudioVideo/
 M.G. Pimentel, G. Abowd, and Y. Ishiguro, "Linking by interacting: A paradigm for authoring hypertext", Proc. of ACM Hypertext '00, San Antonio, May-June 2000.
 A. Hauptmann, "Integrating and using large databases of text, images, video and audio", IEEE Intelligent Systems Magazine, vol. 14, no. 5, pp. 34-35, September/October 1999.
Georgia Tech Lorraine
2 et 3 rue Marconi
57070 Metz, FRANCE
Dr. Hayes has been an Associate Editor in Signal Processing for the IEEE Transactions on ASSP, Chairman of the IEEE ASSP Society Technical Committee on DSP, Secretary-Treasurer of the ASSP Publications Board, member of the Standing Committee on Constitution and Bylaws for the IEEE SP Society, member of the ASSP Administrative Committee, and Chairman of the SP Society Publications Board.. In addition, he served as General Chairman of ICASSP-96. In 1983 he received the Senior Award from the IEEE ASSP Society, in 1984 he received the Presidential Young Investigator Award, and in 1992 he was elected to the grade of Fellow of the IEEE.
Michael J. Mayercik, received the B.E.E. degree from the Georgia Institute of Technology in Atlanta, Georgia, in 1994. He began his graduate study at the University of Stuttgart, Germany in 1994 on a scholarship from the German government, and completed his Masters of Science degree in Electrical Engineering at Georgia Tech Lorraine in Metz, France in 1997. Currently, Mr. Mayercik is in the Center for Signal and Image Processing in Atlanta working on developing and improving distance learning through the Internet.
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