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Project Background and History

BLC/MELC Digital Library Research

Resources Digital Library Video Segmenting Indexing Modules Video Research Policy Other Digital Libraries
The resources used by the BLC/MELC community come from several sources:
  • The National Archives
  • NASA
  • The Discovery Channel
  • Maryland Public Television
  • World Wide Web
Each resource is given a unique identifier and has its metadata captured as part of our indexing process.

Digital Library
Our resources include text, images, video, audio, and Web sites. All of these are available to the teachers online in an electronic format. One of the way teachers can identify these multimedia items is in the Resource Catalog, which offers them several ways to sort the resources.

Video Segmenting
The 100 hours of videos made available to BLC/MELC by Discovery Channel are drawn from a selection of thirty-minute educational shows that had aired on the television in recent years. The process of segmenting these videos is accompanied by a host of considerations that merit special explanation.

Our first consideration is for our users: middle school teachers in Baltimore city schools who are constructing modules (electronic lesson plans) as part of their social studies and science curriculums. In segmenting the video into units, we tried to anticipate how they might use the segment within the context of a subject-specific lesson.

The Discovery videos generally use a narrator, interviews, historical footage, animations, and re-enactments to create interesting and informative presentations. As part of our segmenting efforts, we tease out these different threads; we assume that a teacher interested in longer segments will simply pop the entire tape into a VCR. Consequently, we usually find ourselves segmenting along scene changes. For example, a seven-minute presentation on gravity that is composed of
  • an animated graphic illustrating the concept,
  • a respected scientist elaborating on the implications for space travel,
  • historical footage of Albert Einstein with voice-over of his theories,
  • another animated graphic illustrating how time and space can bend, and
  • closing comments from the respected scientist
broken into five segments. An additional benefit to this approach is that it allows teachers to reconstruct an entire thread (an interview, the animated graphic) if desired. The smaller segments serve as building blocks that teachers can manipulate in the manner that best meets the needs of their students.

The smaller segments also allow for a greater variety of uses. For example, a 60-minute video detailing the life and accomplishments of Benjamin Franklin is clearly something that would be shown in a history or social studies class. However, once segmented, its many fine illustrations of scientific principles and inventions would be ideal for use in a science module. In the case of segmenting educational videos, the sum of the parts is always greater than the whole.

It was often the case that the indexer has to choose between competing bodies of information. For example, in "The Real Thomas Jefferson" there are two very different kinds of information being conveyed by the narration and the video when the camera turns to the American Room at Monticello. The focus of the narration is on the significance of the Native American artifacts that are housed in the room, but the arguably more important or useful information lies in the 360-degree view of the room itself. Rather than segment this scene as the narrator discusses each new artifact, information that could most likely be found offline, one could choose (as we did) to preserve the visual information about the room itself as a sort of virtual field trip for the students, something uniquely suited to the computer environment.

Another way to handle this would simply be to segment this section of the video twice—once for the specific information about the artifacts, a second time for the room as a whole. Unfortunately, this kind of attention to detail and precision would cost a great deal in terms of an indexer's time and the project's money, and so we confined ourselves to a single segmenting of each video.

Information in the videos that was presented as on-screen text (credits, questions for students, lists of related resources) are not saved as a video files. To conserve space and to save time in the classroom (downloading time), this information is saved as image files or, better yet, text files.

Video Catalog (many videos, including Discovery videos, are password protected and can only be accessed by members of the BLC community)
Public Domain Video Catalog

Once segmented and digitized, the video resources are included in the project database, or Resource Catalog. Not only do we include general information about the size of the file, its location, its source, and a brief description, but we also have indexed the items to the middle school curriculum and the outcomes identified by the Maryland State Performance Assessment Program (MSPAP).

From our analysis of the curriculum we identified the following topics in the science curriculum: Animals, Aquatic Habitats, Careers, Chemistry, Ecology, Energy, Forces, Geology, Human Body, Inventions, Meteorology, Plants, Space, and Vehicles. Similarly, we identified the following topics in the social studies curriculum: Arts and Humanities, Careers, Conflicts, Geography, Global Connections, Ideological Movements, Peoples, Religion, U.S. History By Era, U.S. History By Region, World History By Era, and World History By Region.

Drawing directly from the MSPAP literature, we identified the following outcomes for social studies: Culture, Chronology, Environment, Individuals/Groups/Institutions, Political Systems, Economics, Science and Technology, and Civics. Again, from the MSPAP literature we identified the following outcomes for science: Unifying Concepts and Processes, Science As Inquiry, Physical Science, Life Science, Earth and Space Science, Science and Technology, Science In Personal and Social Perspectives, and History of Science.

For a more complete picture of the entire process, visit our Indexer's Manual.

The module constructor is designed to let teachers create their multimedia lessons in an online environment. It has a series of screens with fields for metadata elements and descriptions of what both teacher and student will be doing before, during, and after the lesson. To aid teachers in selecting resources, the Resource Explorer lets teachers visualize the database as a star field. The x and y axes can be manipulated to represent source, topic, outcome, or type of media. The resulting display lets teachers see where the richer collections are and then peruse a sub-collection—for example, videos of aquatic habitats or images from the civil war. If they think a particular video might suit their needs, they can view a short slide show of automatically extracted screen changes to get a quick idea about Content. There are buttons on the tool bar for adding or deleting resources from the module.

The Module Constructor demo is no longer available on-line. Click here to view a paper describing the design and implementation of the earlier prototypes.

Video Research Policy

Other Digital Video Libraries
Digital Libraries for Children: Computational Tools that Support Children as Researchers
Open Video Project
Princeton Deployable


Web Accessibility