Thomas McGee

Video keyframe extraction and filtering: a keyframe is not a keyframe to everyone

In this paper, we describe the keyframe extraction and filtering process within the video content indexing system called Vitamin. The video content filtering system analyzes the source video and presents to the user a visual table of contents using thumbnail images. The tiltering process eliminates keyframes which do not contribute to the overall comprehension of the video contents. The user should he able to access particular points on a VHS tape, or MPEG file using this visual table of contents. We have analyzed over ten hours of video content from dierent movies, home videos, serials. and sitcoms. Our experhnents show that the number of keyframes is reduced to a manageable size, thus enabling only important visual information to be presented to the user.

Growth and characterization of doped KTP crystals

Abstract The conductivity of high temperature solution grown KTP has been lowered by three orders of magnitude by doping with trivalent ions. The uniformity of the doping and the conductivity of the crystals was found to be uniform within a factor of 2. The distribution coefficient is calculated for the trivalent, divalent and monovalent ions used for doping. Ga, Al and Mg doped crystals are colorless and have optical transmission similar to that of undoped KTP. Doping with Cr and V introduce absorption bands in the visible region. The ferroelectric Curie temperature was measured in the Ga and Al doped samples. It was found that doping with 440 ppm Al or 1000 ppm Ga lowered the ferroelectric Curie temperature 7 and 22°C, respectively, from the value of 946δC found for undoped KTP.

Integrated multimedia processing for topic segmentation and classification

We describe integrated multimedia processing for Video Scout, a system that segments and indexes TV programs according to their audio, visual, and transcript information. Video Scout represents a future direction for personal video recorders. In addition to using electronic program guide metadata and a user profile, Scout allows the users to request specific topics within a program. For example, users can request the video clip of the USA president speaking from a half-hour news program. Video Scout has three modules: (i) video pre-processing, (ii) segmentation and indexing, and (iii) storage and user interface. Segmentation and indexing, the core of the system, incorporates a Bayesian framework that integrates information from the audio, visual, and transcript (closed captions) domains. This framework uses three layers to process low, mid, and high-level multimedia information. The high-level layer generates semantic information about TV program topics. This paper describes the elements of the system and presents results from running Video Scout on real TV programs.

Evolvable visual commercial detector

Commercial detection plays an important role in various video segmentation and indexing applications. It provides high-level program segmentation so that other algorithms can be applied on the true program material in the broadcast. It is a challenge to have robust commercial detection methodology for various platforms, content formats, and broadcast styles that are used all over the world. Wide deployment of such an algorithm not only requires the development of new algorithms but also updating and tuning of parameters for existing algorithms. We present visual commercial detectors that rely on features including, luminance, letterbox, and keyframe distance. These detectors were developed after a careful study of the various features that can be extracted during MPEG-encoding process in real time. Due to the intermittent nature of the features, and platform restrictions, the commercial detection relies on a set of thresholds to keep the implementation as simple as possible. We evolved these thresholds using genetic algorithms (GAs) to optimize the performance. We show how a scalar genetic algorithm can locate sets of parameters in a multi-objective space (precision and recall) that outperform the values selected by an expert engineer. We present the results of optimizing a commercial detection algorithm for different data sets and parameter sets. In this paper we show that GAs drastically improved our approach and enabled fast prototyping and performance tuning of commercial detection algorithms.

Video content management in consumer devices

Methods for video content analysis are necessary for the growing amount of video information delivered to consumers today. In this paper, we present a system for video content analysis called Vitamin, which provides management of a home video library. The system presents the user with a visual table of contents that provides an overview of the video content and direct access to particular points in the stored video. In this process, we apply a computationally inexpensive, simple, yet powerful mechanism for cut detection and keyframe filtering. Our initial implementation and results show that this system can perform video content extraction in real time on a low-end platform that matches a visual table of contents extracted by an expert.

Solubility and crystal growth of KTiOPO4 in polyphosphate solvents

Abstract The solubility of KTiOPO4 in K4P2O7, K8P6O19 and K15P13O40 solvents was determined over the temperature range 900 to 980°C. The slope of the solubility curves were dS/dT−3.4x10-3, 2.3x10-3 and 2.1x10-3 g (KTP)/g(flux)·°C, respectively Significant habit modification is observed for crystals grown from K4P2O7.

Self-sealing and self-releasing technique (SSSR) for the crystal growth of II–VI compounds

Abstract A low-pressure melt-growth technique for the growth of II–VI compounds has been developed. It is based on growth in a graphite crucible sealed by the condensed vapors of the II–VI compound. The seal is automatically released by volatilization at the end of the growth procedure, allowing easy removal of the boule and subsequent re-use of the crucible. Wafers of ZnSe, the main material investigated, have been observed with effectively single crystal areas as large as 4.5 cm 2 . The line width of a bound exciton line in photoluminescence has been as narrow as 0.3 meV. ZnS x Se 1− x , CdTe and CdSe have also been grown by this method. Electron-beam-pumped lasers with threshold currents lower than had previously been reported for ZnSe have been made by this method.

Selective video content analysis and filtering

Consumer digital video devices are becoming computing platforms. As computing platforms, digital video devices are capable of crunching the compressed bits into the best displayable picture and delivering enhanced services. Although these deices will primarily aim to continue their traditional functions of display and storage, there are additional functions such as content management for real- time and stored video, tele-shopping, banking, Internet connectivity, and interactive services, which the device could also handle.

Personalizing video recorders using multimedia processing and integration

Current personal Vido recorders make it very easy for consumers to record whole TV programs. Our research however, focuses on personalizing TV at a sub-program level. We use a traditional Content-Based Information Retrieval system architecture consisting of archiving and retrieval modules. The archiving module employs a three-layered, multimodal integration framework to segment, analyze, characterize, and classify segments. The retrieval module relies on users personal preferences to deliver both full programs and video segments of interest. We tested retrieval concepts with real users and discovered that they see more value in segmenting non-narrative programs (e.g. news) than narrative programs (e.g. movies). We benchmarked individual algorithms and segment classification for celebrity and financial segments as instances of non-narrative content. For celebrity segments we obtained a total precision of 94.1% and recall of 85.7%, and for financial segments a total precision of 81.1% and a recall of 86.9%.

A probabilistic layered framework for integrating multimedia content and context information

Automatic indexing of large collections of multimedia data is important for enabling retrieval functions. Current approaches mostly draw on a single or dual modality of video content analysis. Here we describe a framework for the integration of multimedia content and context information, which generalizes and systematizes current methods. Content information in the visual, audio, and text domains, is described at different levels of granularity and abstraction. Context describes the underlying structural information that can be used to constrain the possible number of interpretations. We introduce a probabilistic framework that combines (a) Bayesian networks that describe both content and context and (b) hierarchical priors that describe the integration of content and context. We present an application that uses this framework to segment and index TV programs. We discuss experimental results on segment classification on six and a half hours of broadcast video. In our experiments we used audio context information. Classification results for financial segments yield 83% and for celebrity segments 89%.