Boon-Lock Yeo

Lossless image compression using integer to integer wavelet transforms

Invertible wavelet transforms that map integers to integers are important for lossless representations. We present an approach to build integer to integer wavelet transforms based upon the idea of factoring wavelet transforms into lifting steps. This allows the construction of an integer version of every wavelet transform. We demonstrate the use of these transforms in lossless image compression.

Can invisible watermarks resolve rightful ownerships

Digital watermarks have been proposed in recent literature as the means for copyright protection of multimedia data. In this paper we address the capability of invisible watermarking schemes to resolve copyright ownerships. We will show that rightful ownerships cannot be resolved by current watermarking schemes alone. In addition, in the absence of standardization of watermarking procedures, anyone can claim ownership of any watermarked image. Specifically, we provide counterfeit watermarking schemes that can be performed on a watermarked image to allow multiple claims of rightful ownerships. We also proposed non-invertible watermarking schemes in this paper and discuss in general the usefulness of digital watermarks in identifying the rightful copyright owners. The results, coupled with the recent attacks on some image watermarks, further imply that we have to carefully re-think our approaches to invisible watermarking of images, and re- evaluate the promises, applications and limitations of such digital means of copyright protection.

Extracting story units from long programs for video browsing and navigation

Content based browsing and navigation in digital video collections have been centered on sequential and linear presentation of images. To facilitate such applications, nonlinear and non sequential access into video documents is essential, especially with long programs. For many programs, this can be achieved by identifying underlying story structures which are reflected both by visual content and temporal organization of composing elements. A new framework of video analysis and associated techniques are proposed to automatically parse long programs, to extract story structures and identify story units. The proposed analysis and representation contribute to the extraction of scenes and story units, each representing a distinct locale or event, that cannot be achieved by shot boundary detection alone. Analysis is performed on MPEG compressed video and without a prior models. The result is a compact representation that serves as a summary of the story and allows hierarchical organization of video documents.

Retrieving and visualizing video

Like its traditional database counterpart, a digital video database management system (VDBMS) seeks to provide convenient and efficient access to the information in the database. However, unlike traditional database systems, where the focus is search and indexing techniques, video poses additional challenges and opportunities. This article addresses the special functions and Boon-Lock Yeo and Minerva M. Yeung

Updates to the QBIC system

QBICTM (Query By Image Content) is a set of technologies and associated software that allows a user to search, browse, and retrieve image, graphic, and video data from large on-line collections. This paper discusses current research directions of the QBIC project such as indexing for high-dimensional multimedia data, retrieval of gray level images, and storyboard generation suitable for video. It describes aspects of QBIC software including scripting tools, application interfaces, and available GUIs, and gives examples of applications and demonstration systems using it.

Video content characterization and compaction for digital library applications

In digital libraries and the Internet, large amount of data in various modalities has to be transmitted and delivered across the networks, and is subject to bandwidth constraints and network congestion. Among all multimedia data, video is the most difficult to handle, both in terms of its size and the scarcity of tools and techniques available for efficient delivery, storage and retrieval. Providing tools to help users search and browse large collections of video documents is important. Equally important are the means to deliver and present the essence of video content to the user without noticeable delay. In this paper, we focus on the characterization of video by means of automatic analysis of its visual content and the compact presentation of the underlying story content built upon the derived characteristics. We develop models to capture and characterize video by temporal events, namely, dialogues, actions and story units. We then present these events using succinct visual summaries that depict and differentiate the underlying dramatic elements in an intuitive manner. The combination of video characterization and visual summary offers significant compaction of data size in video far beyond the numbers achieved by traditional video compression, while retaining essential meanings and semantics of the content, and is particularly useful for digital library and Internet applications.

Classification, simplification and dynamic visualization of scene transition graphs for video browsing

The scene transition graph (STG) is a directed graph structure that compactly captures both image content and temporal flow of video. An STG offers a condensed view of the story content, serves as the summary of the clip represented, and allows nonlinear access to its story element. It can serve as a valuable tool for both the analysis of video structure and presentation of high level visual summary for video browsing applications. In this paper, we study new techniques for classification and simplification of the STG, and present better means of visualizing the graph through dynamic visual display and simplified structures. In other words, our techniques improve significantly the existing graph structure to enable more succinct presentation of the graphs which leads to more efficient utilization of the screen spaces. In addition, a technique that captures and presents visually the temporal dynamics of the video sequence is described. We have tested the graph visualization techniques on various programming types and the new tools are found to effectively handle video from a wider variety than the existing STG structure.

Visual content highlighting via automatic extraction of embedded captions on MPEG compressed video

Embedded captions in TV programs such as news broadcasts, documentaries and coverage of sports events provide important information on the underlying events. In digital video libraries, such captions represent a highly condensed form of key information on the contents of the video. In this paper we propose a scheme to automatically detect the presence of captions embedded in video frames. The proposed method operates on reduced image sequences which are efficiently reconstructed from compressed MPEG video and thus does not require full frame decompression. The detection, extraction and analysis of embedded captions help to capture the highlights of visual contents in video documents for better organization of video, to present succinctly the important messages embedded in the images, and to facilitate browsing, searching and retrieval of relevant clips.

Adaptive public watermarking of DCT-based compressed images

We propose an adaptive scheme to embed watermark information in DCT blocks of compressed image data. our scheme is designed to avoid artifacts and prevent an increase in the bit rate of the compressed watermarked image. This is essentially done by judicious selection of appropriate blocks for watermark insertion. We also introduce a block-dependent seed generation algorithm to determine the specific coefficients to modify in a particular block. Our proposed technique is simple to implement in software, and hence suitable for real-time software-only insertion of invisible watermarks in JPEG compressed images, and MPEG or MJPEG video streams. We also demonstrate experimentally that our proposed watermarking scheme actually results in bit rate reduction of JPEG compressed images. The proposed technique can also complement existing DCT-based watermarking schemes for copy protection and detection applications.

On fast microscopic browsing of MPEG-compressed video

Abstract. MPEG has been established as a compression standard for efficient storage and transmission of digital video. However, users are limited to VCR-like (and tedious) functionalities when viewing MPEG video. The usefulness of MPEG video is presently limited by the lack of tools available for fast browsing, manipulation and processing of MPEG video.nIn this paper, we first address the problem of rapid access to individual shots and frames in MPEG video. We build upon the compressed-video-processing framework proposed in [1, 8], and propose new and fast algorithms based on an adaptive mixture of approximation techniques for extracting spatially reduced image sequence of uniform quality from MPEG video across different frame types and also under different motion activities in the scenes. The algorithms execute faster than real time on a Pentium personal computer. We demonstrate how the reduced images facilitate fast and convenient shot- and frame-level video browsing and access, shot-level editing and annotation, without the need for frequent decompression of MPEG video. We further propose methods for reducing the auxiliary data size associated with the reduced images through exploitation of spatial and temporal redundancy. We also address how the reduced images lead to computationally efficient algorithms for video analysis based on intra- and inter-shot processing for video database and browsing applications. The algorithms, tools for browsing and techniques for video processing presented in this paper have been used by many in IBM Research on more than 30 h of MPEG-1 video for video browsing and analysis.