Module 3 Table of Contents
Each advance in video technology has dramatically increased its use in distance education. Today, the front-runners are digital videodiscs (DVDs) and various digital streaming video file formats. Before these video technologies, videocassette recorders (VCRs) expanded how instruction was delivered and expanded the audience for asynchronous learner-paced instruction. The availability of satellite delivery and Internet services has spurred the growth of one-to-many instructional delivery. Videoconferencing technology has allowed visual and audio information to be sent simultaneously over economical telephone and fiber network lines.
Video systems deliver varying levels of picture and sound quality, depending on their compression technology, bandwidth requirements, and cost. Synchronous video systems with high bandwidth capabilities will produce better picture quality but will cost more. The quality of picture and sound you need for your organization’s programs will largely be driven by the programs’ instructional outcomes.
Asynchronous video tools such as videocassettes, DVDs, and streaming video over the Internet may be used to record instructional programs for later viewing or to provide supplemental information to learners. The easiest, most economical way to record an instructional program is to videotape a traditional classroom presentation and then distribute the videotaped material to remote learners. When recording traditional classroom presentations, however, you must carefully consider the needs of asynchronous learners, who will view the presentations in a much different context than did the classroom audience. For example, traditional classroom presentations often include interactions not relevant to asynchronous learners.
To better anticipate the needs of asynchronous audiences, you might produce carefully scripted video programs for distribution. Although production costs can be significant, the end product will be quality instructional programs with reusable learning objects (RLOs). This option is preferred, especially if an instructional program’s content has a reasonable “shelf life.”
Analog vs. Digital
The terms analog and digital refer to the way that information is stored electronically. Analog representation is a continuous waveform that varies by time and intensity, whereas digital representation codes everything into a binary language of ones and zeros. Today’s distance education technology is primarily digital, and will become even more so with the switch to digital television in 2009.
Video Technology: Characteristics
Video technology
- transmits both visual and audio information between sites.
- most closely approximates face-to-face instruction.
- allows real-time communication and transmission of information.
- allows instructors to focus learners’ attention on visual information or activities (e.g., experiments, demonstrations).
- accommodates lecture-based instructional strategies.
- encourages learner interaction and allows all participants to see and hear each other (two-way video).
- requires instructors to manage interaction, especially between or with remote locations.
- may tempt instructors to focus on presentation rather than instructional outcomes.
- requires strong technical support.
- requires a lot of instructor planning.
- may limit nonverbal learner feedback (one-way video).
Video Technology: Applications
Real-time broadcast of video-based instruction is the closest replication of the traditional classroom that distance education technology offers. Synchronous applications of video-based distance education generally use one- or two-way video. Although both technologies allow learners to see and hear their instructors, thus emulating the traditional classroom, the technologies differ somewhat in their instructional characteristics.
One-Way Video
Often used for traditional lecture formats, one-way video technology can be an effective, efficient way to reach remote learners. One-way video technology transmits programs from an originating site to remote sites using satellite, cable/broadcast TV, downloads of video files, or streaming video over the Internet. One-way video gives instructors a rich visual medium in which to teach. Instructors can incorporate visual elements such as photographs, slides, prepared graphics, pre-produced videos, whiteboards, and flip charts. Instructors can also focus the camera on activities they’re performing (e.g., experiments, demonstrations) or on written points they want to emphasize.
Synchronous interaction with one-way video is usually accomplished with telephones or keypad response systems and videoconferencing at a time after the original video was produced. When telephones are used, learners and instructors can interact verbally in real time, allowing questions and discussions. Keypad response systems are good for polling learners’ understanding of a program’s subject matter. Such Internet applications as chat rooms can also allow learner interaction.
The Warriors of the Net video is an example of one-way, pre-produced, downloadable video without interaction.
Two-Way Video
Two-way video technology provides video and audio communication to and from each participating site. Because all sites are equipped with cameras, monitors, and microphones, participants at each site can be seen and heard. Connections between only two sites are called point-to-point connections. Connections between multiple sites are called multipoint connections; multipoint connections typically use a video bridge or multipoint control unit (MCU) to connect sites. Signals between sites can be transmitted over a variety of networks, including telephone, fiber optic, and microwave networks and the Internet. Compressed digital video (CDV), which typically uses telephone lines, is the most common type of two-way video transmission.
There are many webconferencing hosts such as ePop, ooVoo, and iVisit that provide the ability to conduct small meetings via two-way video using webcams attached to the participants' computers. Many collaborative software/groupware applications include the ability to conduct one- and two-way video conferences via webcams including Adobe Acrobat Connect Pro (formerly known as Macromedia/Adobe Breeze), Elluminate, WebEx and the new free Vyew and Yugma platforms. Google has also introduced free one-to-one video chat within their gmail service.
Streaming Video
Streaming video is video that is played as it is being received by the user as opposed to video that is downloaded first and then viewed. Special streaming video servers are used that can send the highly compressed video in small chunks called "packets" (see [* Warriors of the Net] for a video on what packets are and how they move data through the internet).
Although streaming video is becoming more common, instructors and designers should be cognizant of issues concerning bandwidth and learners’ use of dial-up modems, DSL, cable, and other higher speed connections. The slower the connection, the longer the download times and as a result video sometimes can be seen as choppy and halting when the picture and sound don’t sync. When producing video for streaming, it is recommended that you offer it at different quality levels so that learners can choose the version that best matches their technical capabilities. Realtime video refers to the streaming of live video. There are some video tutorials on streaming video at MediaCollege.com
The free Bandwidth Speed Test is a good tool to check the speed of your connection. You can also have your learners try it and report back to you. It will provide results in the form of megabits per second for communication and how many seconds it would take to download a 1MB file. You can then use this information to determine what levels of streaming you should provide as well as how long it would take a student to download the entire video file if streaming was not an option for you or for the learner due to other technical limitations.
If you are just beginning to explore recording and editing video, you may want to try some of the free, web-based video editing/mashup applications such as Kaltura and Jing. There area also many video hosting services that will convert your video files into (normally Flash-based) streaming files and provide access for your learners. If you are investigating third-party hosting services instead of maintaining your own streaming server you need to carefully review the hosting agreement. Many hosting companies will retain the right to resell your videos for their own profit while they are hosting them for you. Most free services will place advertising before or around your video. You also may want to control who can access your video and who can comment on it. Examples of hosting sites include YouTube, blip.tv, Viddler, and Revver.
While not exactly video, SlideShare and authorStream provide a way to share narrated PowerPoint presentations.
DVDs, HD DVDs, and DVD-ROMs
There are a variety of media options for distributing instructional video if the previous options are not appropriate for your situation. With the advent of very low cost DVD players and the inclusion of DVD drives on most newer computers, these discs are an easy way to package instructional media including video, interactive simulations, and text.
