CBCD Based on Color Features and Landmark MDS-Assisted Distance Estimation

Content-Based Copy Detection (CBCD) of digital videos is an important research field that aims at the identification of modified copies of an original clip, e.g., on the Internet. In this application, the video content is uniquely identified by the content itself, by extracting some compact features that are robust to a certain set of video transformations. Given the huge amount of data present in online video databases, the computational complexity of the feature extraction and comparison is a very important issue. In this paper, a landmark based multi-dimensional scaling technique is proposed to speed up the detection procedure which is based on exhaustive search and the MPEG-7 Dominant Color Descriptor. The method is evaluated under the MPEG Video Signature Core Experiment conditions, and simulation results show impressive time savings at the cost of a slightly reduced detection performance

Highly efficient low-level feature extraction for video representation and retrieval.

PhDWitnessing the omnipresence of digital video media, the research community has raised the question of its meaningful use and management. Stored in immense multimedia databases, digital videos need to be retrieved and structured in an intelligent way, relying on the content and the rich semantics involved. Current Content Based Video Indexing and Retrieval systems face the problem of the semantic gap between the simplicity of the available visual features and the richness of user semantics. This work focuses on the issues of efficiency and scalability in video indexing and retrieval to facilitate a video representation model capable of semantic annotation. A highly efficient algorithm for temporal analysis and key-frame extraction is developed. It is based on the prediction information extracted directly from the compressed domain features and the robust scalable analysis in the temporal domain. Furthermore, a hierarchical quantisation of the colour features in the descriptor space is presented. Derived from the extracted set of low-level features, a video representation model that enables semantic annotation and contextual genre classification is designed. Results demonstrate the efficiency and robustness of the temporal analysis algorithm that runs in real time maintaining the high precision and recall of the detection task. Adaptive key-frame extraction and summarisation achieve a good overview of the visual content, while the colour quantisation algorithm efficiently creates hierarchical set of descriptors. Finally, the video representation model, supported by the genre classification algorithm, achieves excellent results in an automatic annotation system by linking the video clips with a limited lexicon of related keywords

Inferring semantics from structural annotations of audio–visual documents

In this paper, a new approach for semantic extraction is proposed. Assuming that the semantics of interest associated to a multimedia document is subjective and that the user cannot easily construct a semantic description on different abstraction levels, we propose an interactive tool which allows to generate a semantic description by organizing an audio-visual document. The structural decomposition is the result of a guided annotation by the user: the user segments the input sequence in events, assigns each event to a specific class and includes other informations such as time, place and contained objects. The classification process can evolve dynamically, which means that the user can organize the semantics with various personalized and more specialized classes. Using the resulting structural descriptions and classification, our method automatically generates a richer semantic description. The system is totally MPEG-7 complaint

COSMOS-7: Video-oriented MPEG-7 scheme for modelling and filtering of semantic content

MPEG-7 prescribes a format for semantic content models for multimedia to ensure interoperability across a multitude of platforms and application domains. However, the standard leaves it open as to how the models should be used and how their content should be filtered. Filtering is a technique used to retrieve only content relevant to user requirements, thereby reducing the necessary content-sifting effort of the user. This paper proposes an MPEG-7 scheme that can be deployed for semantic content modelling and filtering of digital video. The proposed scheme, COSMOS-7, produces rich and multi-faceted semantic content models and supports a content-based filtering approach that only analyses content relating directly to the preferred content requirements of the user

Modeling image databases using Xml schema

This thesis presents a model for still images in order to support content-based querying and browsing by hierarchical tree structures and object relational graphs. We use the extensible markup language (XML) schema to illustrate and exemplify the proposed model because of its interoperability and flexibility advantages. Of primary interest is the notion of complex types and referential integrity to fully describe the physical and semantic properties of images. XQuery is used to support query processing. We further show how these complex types of XML schema can be used to overcome the shortcomings of reported image database descriptions in the literature