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Comparison of automatic shot boundary detection algorithms

Proceedings of SPIE - The International Society for Optical Engineering 1999年 3656卷 290-301页

作者： Lienhart, Rainer Intel Corp Santa Clara United States

Various methods of automatic shot boundary detection have been proposed and claimed to perform reliably. Although the detection of edits is fundamental to any kind of video analysis since it segments a video into its basic components, the shots, only few comparative investigations on early shot boundary detection algorithms have been published. These investigations mainly concentrate on measuring the edit detection performance, however, do not consider the algorithms' ability to classify the types and to locate the boundaries of the edits correctly. This paper extends these comparative investigations. More recent algorithms designed explicitly to detect specific complex editing operations such as fades and dissolves are taken into account, and their ability to classify the types and locate the boundaries of such edits are examined. The algorithms' performance is measured in terms of hit rate, number of false hits, and miss rate for hard cuts, fades, and dissolves over a large and diverse set of video sequences. The experiments show that while hard cuts and fades can be detected reliably, dissolves are still an open research issue. The false hit rate for dissolves is usually unacceptably high, ranging from 50% up to over 400%. Moreover, all algorithms seem to fail under roughly the same conditions.

关键词： image analysis

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Digital signature of color images using amplitude modulation 5

Digital signature of color images using amplitude modulation

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conference on storage and retrieval for image and video databases V

作者： Kutter, M Jordan, F Bossen, F Swiss Federal Institute of Technology (Switzerland)

ISBN: (纸本)0819424331

Watermarking techniques, also referred to as digital signature, sign images by introducing changes that are imperceptible to the human eye but easily recoverable by a computer program. Generally, the signature is a number which identifies the owner of the image. The locations in the image where the signature is embedded are determined by a secret key. Doing so prevents possible pirates from easily removing the signature. Furthermore, it should be possible to retrieve the signature from an altered image. Possible alternations of signed images include blurring, compression and geometrical transformations such as rotation and translation. These alterations are referred to as attacks. A new method based on amplitude modulation is presented. Single signature bits are multiply embedded by modifying pixel values in the blue channel. These modifications are either additive or subtractive, depending on the value of the bit, and proportional to the luminance. This new method has shown to be resistant to both classical attacks, such as filtering, and geometrical attacks. Moreover, the signature can be extracted without the original image.

关键词： watermarking digital signature copyright color image geometrical attack steganography

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Multifeature image and video content-based storage and retrieval

Multifeature image and video content-based storage and retri...

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conference on Multimedia storage and Archiving Systems

作者： Ardizzone, E LaCascia, M Univ. of Palermo (Italy)

ISBN: (纸本)0819423181

In this paper we present most recent evolution of JACOB, a system we developed for image and video content-based storage and retrieval. The system is based on two separate archives: a ''Features DB'' and a ''Raw-data DB''. When a user puts a query, a search is done in the ''Features DB'';the selected items are taken from the ''Raw-data DB'' and shown to the user. Two kinds of sessions are allowed: ''database population'' and ''database querying''. During a ''database population'' session the user inserts new data into the archive. The input data can consist of digital images or videos. videos are split into shots and for each shot one or more representative frames (r-frames) are automatically extracted. Shots and r-frames are then characterized, either in automatic or semi-automatic way, and stored in the archives. Automatic features' extraction consists of computing some low-level global features. Semi-automatic features' extraction is done by using annotation tools that perform operations that aren't currently possible with fully automatic methods. To this aim semi-automatic motion based segmentation and labeling tools have been developed. During a ''database querying'' session, queries direct or by example are allowed. Queries (direct or by example) may be iterated and variously combined to satisfy the query in the smallest number of steps. Multifeature querying is based on statistical analysis of the feature space.

关键词： databases video Feature extraction image segmentation Motion models image retrieval Zoom lenses Optical flow Computing systems image storage

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image categorization using NxM-grams 5

Image categorization using NxM-grams

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conference on storage and retrieval for image and video databases V

作者： Soffer, A Univ. of Maryland/Baltimore County and NASA Goddard Space Flight Ctr. (United States)

ISBN: (纸本)0819424331

A method for categorizing images using N x M-grams is presented. The goal of categorization is to find all images from the same category as a given query image. Some example categories are hand-written documents, printed documents, floor plans, satellite images, and fingerprints. The categorization method is based on the N-gram technique that is commonly used for determining similarity of text documents. Intuitively an N x M-gram is a small pattern in an image. The hypothesis that two images that have the same recurring patterns are likely to belong to the same category is examined. The notion of N x M-grams is defined and the process of computing an image profile in terms of its N x M-grams termed an N x M-gram vector is explained. Two similarity measures to compare images based on their N x M-gram vectors are proposed. Results of an experiment on images from various categories are presented. The two similarity measures for N x M-gram vectors are compared to each other as well as to results of categorization using a method based on color distribution features. The results show that for our test images N x M-gram based methods were more successful in finding images from the same category as a given query image than color distribution based methods.

关键词： retrieval by content image categorization N-grams image similarity image databases document analysis

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Dimensionality reduction for image retrieval

Dimensionality reduction for image retrieval

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IEEE International conference on image Processing (ICIP 2000)

作者： Wu, P Manjunath, BS Shin, HD Univ Calif Santa Barbara Dept Elect & Comp Engn Santa Barbara CA 93106 USA

ISBN: (纸本)0780362985

Dimensionality reduction methods are of interest in applications such as content based image and video retrieval. In large multimedia databases, it may not be practical to search through the entire database in order to retrieve the nearest neighbors of a query. Good data structures for similarity search and indexing are needed, and the existing data structures do not scale well for the high dimensional multimedia descriptor-a. We investigate the use of weighted multi-dimensional scaling (WMDS) for dimensionality reduction. The main objective of the WMDS is to preserve the local topology of the high dimensional space, i.e,, to map the nearest neighbors in the high dimensional space to nearest neighbors in the lower dimensional space. In addition to the well known retrieval accuracy as a measure of performance, we propose two additional measures that take into account the ordinal relationships among the nearest neighbors. Experimental results are given.

关键词： image retrieval

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Automated analysis and annotation of basketball video 5

Automated analysis and annotation of basketball video

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conference on storage and retrieval for image and video databases V

作者： Saur, DD Tan, YP Kulkarni, SR Ramadge, J Princeton Univ. (United States)

ISBN: (纸本)0819424331

Automated analysis and annotation of video sequences are important for digital video libraries, content-based video browsing and data mining projects. A successful video annotation system should provide users with useful video content summary in a reasonable processing time. Given the wide variety of video genres available today, automatically extracting meaningful video content for annotation still remains hard by using current available techniques. However, a wide range video has inherent structure such that some prior knowledge about the video content can be exploited to improve our understanding of the high-level video semantic content. In this paper, we develop tools and techniques for analyzing structured video by using the low-level information available directly from MPEG compressed video. Being able to work directly in the video compressed domain can greatly reduce the processing time and enhance storage efficiency. As a testbed, we have developed a basketball annotation system which combines the low-level information extracted from MPEG stream with the prior knowledge of basketball video structure to provide high level content analysis, annotation and browsing for events such as wide-angle and close-up views, fast breaks, steals, potential shots, number of possessions and possession times. We expect our approach can also be extended to structured video in other domains.

关键词： structured video analysis basketball video content annotation browsing indexing MPEG compressed data wide-angle and close-up camera views intra-coded block count

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Using content models to build audio-video summaries

Using content models to build audio-video summaries

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7th storage and retrieval for image and video databases conference

作者： Saarela, J Merialdo, B Inst Eurecom F-06904 Sophia Antipolis France

ISBN: (纸本)0819431273

The amount of digitized video in video archives is becoming so huge that easier access and content browsing tools are desperately needed. Also, video is no longer one big piece of data but a collection of useful smaller building blocks that can be accessed and used independently from the original context of presentation. In this paper, we demonstrate a content model for audio-video sequences with the purpose of enabling the automatic generation of video summaries. The model is based on descriptors which indicate various properties and relations of audio and video segments. In practice, these descriptors could either be generated automatically by analysis methods, or produced manually (or computer-assisted) by the content provider himself. We analyze the requirements and characteristics of the different data segments with respect to the problem of summarization, and we define our model as a set of constraints which allow to produce good quality summaries.

关键词： video analysis summary segmentation audio-video synchronization presentation constraints

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Indexing in video databases

Indexing in video databases

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storage and retrieval for image and video databases iii

作者： Hampapur, Arun Jain, Ramesh C. Weymouth, Terry E. Univ. of Michigan Ann Arbor MI USA

ISBN: (纸本)081941767X

A video database provides content based access to video. This is achieved by organizing or indexing video data based on some set of features. This paper defines the problem of video indexing based on video data models. The procedure required to index video data is outlined. The use of semi-automatic techniques to speed up the indexing processes are explored. These techniques use image motion features to aid in the indexing process. The techniques developed have been applied to video data from cable television feed.

关键词： Indexing (of information)

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Synthetic summaries of video sequences using a multiresolution based key frame selection technique in a perceptually uniform color space

Synthetic summaries of video sequences using a multiresoluti...

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IEEE International conference on image Processing (ICIP 2000)

作者： Campisi, P Neri, A Univ Roma Roma Tre Dipartimento Ingn Elettron I-00146 Rome Italy

ISBN: (纸本)0780362985

video databases are very demanding systems as far as mass storage requirements and computational resources necessary to perform common database operations, such as browsing and retrieval, are required. These operations can be simplified both in terms of computational complexity and of processing time by performing them on an ensemble of frames, called key frames, representative of the content units (shots) in which a video can be segmented. In this contribution an adaptive key frames extraction method based on a wavelet based multiresolution analysis in a perceptually uniform color space is presented. Experimental results that show the effectiveness of the proposed technique to select key frames summarizing the video's content, are finally provided.

关键词： image segmentation

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Multi-media indexing over the web 5

Multi-media indexing over the web

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conference on storage and retrieval for image and video databases V

作者： Agnew, B Faloutsos, C Wang, ZY Welch, D Xue, XG Univ. of Maryland/College Park (United States) Univ. of Maryland/College Park and U.S. Army (United States)

ISBN: (纸本)0819424331

There has been work on database systems that can retrieve multimedia objects by their content. We are extending this work by using the World Wide Web as source and storage for multimedia objects much like current text search engines do for textual information. A system that can access all types of multimedia objects by their content is a formidable task and improvements are constantly being made to indexing techniques. We have taken an important first step in demonstrating the viability of this technique while laying the groundwork for a larger, more capable system. We have implemented a simple indexing scheme while concentrating on building the infrastructure to support this system. Our system can retrieve references to images on the WWW, index those images, and store those images using spatial access methods. We then use query by example to find a set of images on the WWW that resemble our query image. Due to its design, it is easy to include additional context features, to substitute different indexing schemes, and add other types of multimedia to our system like time sequences, voice and video.

关键词： multimedia image indexing spatial database content-based retrieval World Wide Web

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