Anthony Hughes

How fast is too fast? evaluating fast forward surrogates for digital video

To support effective browsing, interfaces to digital video libraries should include video surrogates (i.e., smaller objects that can stand in for the videos in the collection, analogous to abstracts standing in for documents). The current study investigated four variations (i.e., speeds) of one form of video surrogate: a fast forward created by selecting every Nth frame from the full video. In addition, it tested the validity of six measures of user performance when interacting with video surrogates. Forty-five study participants interacted with all four versions of the fast forward surrogate, and completed all six performance tasks with each. Surrogate speed affected performance on four of the measures: object recognition (graphical), action recognition, linguistic gist comprehension (full text), and visual gist comprehension. Based on these results, we recommend a fast forward default speed of 1:64 of the original video keyframes. In addition, users should control the choice of fast forward speed to adjust for content characteristics and personal preferences.

Text or pictures? an eyetracking study of how people view digital video surrogates

One important user-oriented facet of digital video retrieval research involves how to abstract and display digital video surrogates. This study reports on an investigation of digital video results pages that use textual and visual surrogates. Twelve subjects selected relevant video records from results lists containing titles, descriptions, and three keyframes for ten different search tasks. All subjects were eye-tracked to determine where, when, and how long they looked at text and image surrogates. Participants looked at and fixated on titles and descriptions statistically reliably more than on the images. Most people used the text as an anchor from which to make judgments about the search results and the images as confirmatory evidence for their selections. No differences were found whether the layout presented text or images in left to right order.

Video browsing interfaces for the open video project

The Open Video Project is an on-going effort to develop an open source digital video collection that can be used by the research community and ultimately serve an even broader audience. The initial collection contains video or metadata for more than 1600 digitized video segments comprising nearly half a terabyte of content. Our primary goals for this project are to provide free digital video content to people doing a wide variety of research, to develop a collaborative research environment for people interested in digital video, and to provide a testbed for our own video browsing interface work. Each of these goals fit within a broader mission to understand how people think about, seek, and use digital video. This demonstration summarizes the current status of the project through a brief tour of the Open Video web site, describes our current work in developing surrogates to preview video segments, and shows an innovative video browsing interface we are developing.

The role of narrative in understanding digital video: An exploratory analysis

Narrative is perhaps the oldest and most widely used form for organizing information and human experience, thus, it is not surprising that there is a significant body of research concerning narrative and its importance to comprehension and understanding. One important outcome of this research is the concept of narrative intelligence, the human tendency to fit experience into narrative form. This research is extremely relevant to information seeking in general and sense-making1 in particular. This paper outlines the basic principles and research supporting the concept of narrative intelligence and its applicability to the ways in which people make sense of digital video. We explore relevant theory and research in sense-making, surrogates, narrative, and narrative intelligence and then present the preliminary results of two research studies. The first clarifies and operationalizes the concept of narrative as it relates to video. The second demonstrates how narrativity can have significant effects on information seeking and sense-making in digital video. Results from these studies have implications for how syntactic form can be used as a means of indexing digital video.

Measuring User Performance during Interactions with Digital Video Collections.

With more and more digital videos found online, video retrieval researchers have begun to create various representations or surrogates for digital videos, such as poster frames, storyboards, video skims and fast forwards. How to evaluate the effectiveness of these video surrogates has become an issue for researchers. This paper proposes two general classes of user tasks—recognition tasks and tasks requiring inference—for which performance measures were developed. The measures include graphical object recognition, textual object recognition, action recognition, free-text gist determination, multiple-choice gist determination and visual gist determination. The preliminary results from two user studies applying these six measures are also discussed in this paper.