Abstract:
Blackboard-style lecture videos are popular, but learning using existing video player interfaces can be challenging. Viewers cannot
consume the lecture material at their own pace, and the content is
also difficult to search or skim. For these reasons, some people prefer
lecture notes to videos. To address these limitations, we present
Visual Transcripts, a readable representation of lecture videos that
combines visual information with transcript text. To generate a Visual
Transcript, we first segment the visual content of a lecture into
discrete visual entities that correspond to equations, figures, or lines of text. Then, we analyze the temporal correspondence between the
transcript and visuals to determine how sentences relate to visual
entities. Finally, we arrange the text and visuals in a linear layout
based on these relationships. We compare our result with a standard
video player, and a state-of-the-art interface designed specifically
for blackboard-style lecture videos. User evaluation suggests
that users prefer our interface for learning and that our interface is
effective in helping them browse or search through lecture videos.