Abstract Background Continuous enzyme kinetic assays are often used in high-throughput applications, as they allow rapid acquisition of large amounts of kinetic data and increased confidence compared to discontinuous assays. However, data analysis is often rate-limiting in high-throughput enzyme assays, as manual inspection and selection of a linear range from individual kinetic traces is cumbersome and prone to user error and bias. Currently available software programs are specialized and designed for the analysis of complex enzymatic models. Despite the widespread use of initial rate determination for processing kinetic data sets, no simple and automated program existed for rapid analysis of initial rates from continuous enzyme kinetic traces. Results An Interactive Continuous Enzyme Kinetics Analysis Tool (ICEKAT) was developed for semi-automated calculation of initial rates from continuous enzyme kinetic traces with particular application to the evaluation of Michaelis-Menten and EC 50 /IC 50 kinetic parameters, as well as the results of high-throughput screening assays. ICEKAT allows users to interactively fit kinetic traces using convenient browser-based selection tools, ameliorating tedious steps involved in defining ranges to fit in general purpose programs like Microsoft Excel and Graphpad Prism, while still maintaining simplicity in determining initial rates. As a test case, we quickly analyzed over 500 continuous enzyme kinetic traces resulting from experimental data on the response of the protein lysine deacetylase SIRT1 to small-molecule activators. Conclusions ICEKAT allows simultaneous visualization of individual initial rate fits and the resulting Michaelis-Menten or EC 50 /IC 50 kinetic model fits, as well as hits from high-throughput screening assays. In addition to serving as a convenient program for practicing enzymologists, ICEKAT is also a useful teaching aid to visually demonstrate in real-time how incorrect initial rate fits can affect calculated Michaelis-Menten or EC 50 /IC 50 kinetic parameters. For the convenience of the research community, we have made ICEKAT freely available online at https://icekat.herokuapp.com/icekat .

This article reprises the description of the Berkeley software-only MPEG-1 video decoder originally published in the proceedings of the 1st International ACM Conference on Multimedia in 1993. The software subsequently became widely used in a variety of research systems and commercial products. Its main impact was to provide a platform for experimenting with streaming compressed video and to expose the strengths and weaknesses of software-only video decoding using general purpose computing architectures. This article compares the original performance results with experiments run on a modern processor to demonstrate the gains of processing power in the past ten years relative to this specific application and discusses the history of MPEG-1 video software decoding and the Berkeley MPEG research group.

Despite recent advances in authoring systems and tools, creating multimedia presentations remains a labor-intensive process. This paper describes a system for automatically constructing structured multimedia documents from live presentations. The automatically produced documents contain synchronized and edited audio, video, images, and text. Two essential problems, synchronization of captured data and automatic editing, are identified and solved.

This paper addresses the problem of sending an MPEG-encoded video stream over a channel of limited bandwidth. When there is insufficient bandwidth available for the rate at which the sequence was encoded, some data must be dropped. In this paper we give fast algorithms to determine a prioritization of the data that optimizes the visual quality of the received video sequence in the sense that the maximum gap of unplayable frames is minimized. Our results are obtained in a new model of encoded video data that is applicable to MPEG and other encoding technologies. The model identifies a certain key relationship between the play order and dependence order of frames that allows fast determination of optimal send orders by dynamic programming.

This paper presents a new approach for constructing libraries for building processing-intensive multimedia software. Such software is currently constructed either "from scratch" or by using high-level libraries. We have found that the second approach produces inefficient code, while the first approach is time-consuming. We therefore designed and implemented Dali, a set of reusable, high-performance primitives and abstractions that are at an intermediate point in this design space. By decomposing common multimedia data types and operations into thin abstractions and primitives, programs written using Ball are shorter and more reusable than hand-tuned C code, yet achieve competitive performance. This paper describes the design and implementation of Dali.

We present a new technique for morphing two video sequences.Our approach extends still image metamorphosis techniques to video by performing motion tracking on the objects.Besides reducing the amount of user input required to morph two sequences by an order of magnitude, the additional motion information helps us to segment the image into foreground and background parts.By morphing these parts independently and overlaying the results, output quality is improved.We compare our approach to conventional motion image morphing techniques in terms of the quality of the output image and the human input required.

Current video-conferencing systems provide a "video-ins-window" user interface.This paper presents a distributed video-conferencing system called CU-SeeMe VR that embeds live video and audio conferencing in a virtual space.This paper describes a prototype implementation of CU-SeeMe VR, including the user interface, system architecture, and a detailed look at the enabling technologies.Future directions and the implications of the virtual reality metaphor are discussed.

The emergence of audio and video data types in databases will require new information retrieval methods adapted to the specific characteristics and needs of these data types. An effective and natural way of querying a musical audio database is by humming the tune of a song. In this paper, a system for querying an audio database by humming is described along with a scheme for representing the melodic information in a song as relative pitch changes. Relevant difficulties involved with tracking pitch are enumerated, along with the approach we followed, and the performance results of system indicating its effectiveness are presented.

No abstract available.

This paper introduces a set of techniques for processing video data compressed using JPEG compression at near real-time rates on current generation workstations. Performance is improved over traditional methods by processing video data in compressed form, avoiding compression and decompression and reducing the amount of data processed. An approximation technique called condensation is developed that further reduces the complexity of the operation. The class of operations that are computable using the techniques developed in this paper are called linear, global digital specials effects (LGDSEs), and represent those effects where a pixel in the output image is a linear combination of pixels in the input image. Many important video processing problems, including convolution, scaling, rotation, translation, and transcoding can be expressed as LGDSEs.

The design and implementation of a software decoder for MPEG video bitstreams is described. The software has been ported to numerous platforms including PC's, workstations, and mainframe computers. Performance comparisons are given for several different bitstreams and platforms including a unique metric devised to compare price/performance across different platforms (percentage of required bit rate per dollar). We also show that memory bandwidth is the primary limitation in performance of the decoder, not the computational complexity of the inverse discrete cosine transform as is commonly thought