Quality of Service for Information Access

Information is available in many forms from different sources, in distributed locations; access to information is supported by networks of varying performance; the cost of accessing and transporting the information varies for both the source and the transport route. Users who vary in their preferences, background knowledge required to interpret the information and motivation for accessing it, gather information to perform many different tasks. This position paper outlines some of these variations in information provision and access, and explores the impact these variations have on the user’s task performance, and the possibilities they make available to adapt the user interface for the presentation of information

Video summarisation: A conceptual framework and survey of the state of the art

This is the post-print (final draft post-refereeing) version of the article. Copyright @ 2007 Elsevier Inc.Video summaries provide condensed and succinct representations of the content of a video stream through a combination of still images, video segments, graphical representations and textual descriptors. This paper presents a conceptual framework for video summarisation derived from the research literature and used as a means for surveying the research literature. The framework distinguishes between video summarisation techniques (the methods used to process content from a source video stream to achieve a summarisation of that stream) and video summaries (outputs of video summarisation techniques). Video summarisation techniques are considered within three broad categories: internal (analyse information sourced directly from the video stream), external (analyse information not sourced directly from the video stream) and hybrid (analyse a combination of internal and external information). Video summaries are considered as a function of the type of content they are derived from (object, event, perception or feature based) and the functionality offered to the user for their consumption (interactive or static, personalised or generic). It is argued that video summarisation would benefit from greater incorporation of external information, particularly user based information that is unobtrusively sourced, in order to overcome longstanding challenges such as the semantic gap and providing video summaries that have greater relevance to individual users

Detecting the presence of large buildings in natural images

This paper addresses the issue of classification of lowlevel features into high-level semantic concepts for the purpose of semantic annotation of consumer photographs. We adopt a multi-scale approach that relies on edge detection to extract an edge orientation-based feature description of the image, and apply an SVM learning technique to infer the presence of a dominant building object in a general purpose collection of digital photographs. The approach exploits prior knowledge on the image context through an assumption that all input images are �outdoor�, i.e. indoor/outdoor classification (the context determination stage) has been performed. The proposed approach is validated on a diverse dataset of 1720 images and its performance compared with that of the MPEG-7 edge histogram descriptor

Ranking structured documents using utility theory in the Bayesian network retrieval model

In this paper a new method based on Utility and Decision theory is presented to deal with structured documents. The aim of the application of these methodologies is to refine a first ranking of structural units, generated by means of an Information Retrieval Model based on Bayesian Networks. Units are newly arranged in the new ranking by combining their posterior probabilities, obtained in the first stage, with the expected utility of retrieving them. The experimental work has been developed using the Shakespeare structured collection and the results show an improvement of the effectiveness of this new approach

Video browsing interfaces and applications: a review

We present a comprehensive review of the state of the art in video browsing and retrieval systems, with special emphasis on interfaces and applications. There has been a significant increase in activity (e.g., storage, retrieval, and sharing) employing video data in the past decade, both for personal and professional use. The ever-growing amount of video content available for human consumption and the inherent characteristics of video data—which, if presented in its raw format, is rather unwieldy and costly—have become driving forces for the development of more effective solutions to present video contents and allow rich user interaction. As a result, there are many contemporary research efforts toward developing better video browsing solutions, which we summarize. We review more than 40 different video browsing and retrieval interfaces and classify them into three groups: applications that use video-player-like interaction, video retrieval applications, and browsing solutions based on video surrogates. For each category, we present a summary of existing work, highlight the technical aspects of each solution, and compare them against each other

The ToCAI DS for audio-visual documents. Structure and concepts

This document complements the description of the audio-visual (AV) description scheme (DS) called Table of Content-Analytical Index (TOCAI) proposed in MPEG-7 CFP that was evaluated in Lancaster (February 1999). This DS provides a hierarchical description of the time sequential structure of a multimedia document (suitable for browsing) together with an “analytical index” of AV objects of the document (suitable for retrieval). The TOCAI purposes and general characteristics are explained. The detailed structure of the DS is presented by means of UML notation as well, to clarify some issues that were not included in the original proposal. Some examples of XML instantiation are enclosed as well. Then an application example is shown. For an indication on how the TOCAI DS matches MPEG-7 requirements and evaluation criteria, refer to the original proposal submission

Methods and apparatus for constructing and implementing a universal extension module for processing objects in a database

Methods and apparatus for providing a multi-tier object-relational database architecture are disclosed. In one illustrative embodiment of the present invention, a multi-tier database architecture comprises an object-relational database engine as a top tier, one or more domain-specific extension modules as a bottom tier, and one or more universal extension modules as a middle tier. The individual extension modules of the bottom tier operationally connect with the one or more universal extension modules which, themselves, operationally connect with the database engine. The domain-specific extension modules preferably provide such functions as search, index, and retrieval services of images, video, audio, time series, web pages, text, XML, spatial data, etc. The domain-specific extension modules may include one or more IBM DB2 extenders, Oracle data cartridges and/or Informix datablades, although other domain-specific extension modules may be used

Indexing Audio-Visual Sequences by Joint Audio and Video Processing

The focus of this work is oriented to the creation of a content-based hierarchical organisation of audio-visual data (a description scheme) and to the creation of meta-data (descriptors) to associate with audio and/or visual signals. The generation of efficient indices to access audio-visual databases is strictly connected to the generation of content descriptors and to the hierarchical representation of audio-visual material. Once a hierarchy can be extracted from the data analysis, a nested indexing structure can be created to access relevant information at a specific level of detail. Accordingly, a query can be made very specific in relationship to the level of detail that is required by the user. In order to construct the hierarchy, we describe how to extract information content from audio-visual sequences so as to have different hierarchical indicators (or descriptors), which can be associated to each media (audio, video). At this stage, video and audio signals can be separated into temporally consistent elements. At the lowest level, information is organised in frames (groups of pixels for visual information, groups of consecutive samples for audio information). At a higher level, low-level consistent temporal entities are identified: in case of digital image sequences, these consist of shots (or continuous camera records) which can be obtained by detecting cuts or special effects such as dissolves, fade in and fade out; in case of audio information, these represent consistent audio segments belonging to one specific audio type (such as speech, music, silence, ...). One more level up, patterns of video shots or audio segments can be recognised so as to reflect more meaningful structures such as dialogues, actions, ... At the highest level, information is organised so as to establish correlation beyond the temporal organisation of information, allowing to reflect classes of visual or audio types: we call these classes idioms. The paper ends with a description of possible solutions to allow a cross-modal analysis of audio and video information, which may validate or invalidate the proposed hierarchy, and in some cases enable more sophisticated levels of representation of information content