IEEE Transactions on Circuits and Systems for Video Technology

A new technology is proposed for audio-video synchronization in multimedia applications where talking human faces, either natural or synthetic, are employed for interpersonal communication services, home gaming, advanced multimodal interfaces, interactive entertainment, or in movie production. Facial sequences, in fact, represent an acoustic-visual source characterized by two strongly correlated c... View full abstract»

The main difficulty in global motion parameters estimation resides in the disturbance of independently moving objects. The algorithm presented in this letter exploits global motion information not only from stationary objects and the image background, but also from independently moving objects. Simulation results show that the new algorithm is computationally fast and robust to the disturbance cau... View full abstract»

The bit-number allocation strategy of Test Model 5 (TM5) may cause the coding quality to decrease and the buffer to overflow at scene changes, therefore a new algorithm on MPEG-2 target bit-number allocation is proposed in this letter. Here the influence of scene changes on coding quality is analyzed and an approach to improve the coding performance at scene changes is presented to avoid a sharp q... View full abstract»

Coding of HDTV and super high definition video requires not only high performance compression but also compatibility and scalability to satisfy transmission channels of various speeds and capacity and receivers working at different resolutions. A compatible and scalable coding scheme has been developed for these video signals. Wavelet decomposition is performed such that the low frequency band is ... View full abstract»

Digital video archives are likely to be accessible on distributed networks which means that the data are subject to network congestion and bandwidth constraints. To enable new applications and services of digital video, it is not only important to develop tools to analyze and browse video, view query results, and formulate better searches, but also to deliver the essence of the material in compact... View full abstract»

This paper describes algorithms that were developed for a real-time stereoscopic videoconferencing systems with viewpoint adaptation. The goal is a real telepresence illusion, which is achieved by synthesis of intermediate views from a stereoscopic camera shot with a rather large baseline. The actual viewpoint will be adapted according to the head position of the viewer, such that the impression o... View full abstract»

In this paper, we introduce a new fast search block matching motion estimation algorithm with high performance. Based on the center-biased characteristic for most of the video sequences, the proposed algorithm can jointly minimize the error image and total number of bits spent on the motion vectors with much reduced computational complexity. Simulation results show that the proposed algorithm can ... View full abstract»

This paper presents an evaluation of several well-known block-matching motion estimation algorithms from a system-level very large scale integration (VLSI) design viewpoint. Because a straightforward block-matching algorithm (BMA) demands a very large amount of computing power, many fast algorithms have been developed. However, these fast algorithms are often designed to merely reduce arithmetic o... View full abstract»

Most fast block-matching motion estimation (BMME) algorithms are designed to minimize the search positions (or checking points) in a given search range in order to speed up the computation. In this paper, we introduce a fast BMME algorithm based on the consideration of hardware implementation. We use a one-dimensional (1-D) systolic array as the basic computing engine. In order to utilize this eng... View full abstract»

Visual (image and video) database systems require efficient indexing to enable fast access to the images in a database. In addition, the large memory capacity and channel bandwidth requirements for the storage and transmission of visual data necessitate the use of compression techniques. Vector quantization (VQ) is an efficient technique for low bit-rate image and video compression. In addition, t... View full abstract»

We consider the placement of scalable video data on single and multiple disks for storage and real-time retrieval. For the single-disk case, we extend the principle of constant frame grouping from constant bit rate (CBR) to variable bit rate (VBR) scalable video data. When the number of admitted users exceeds the server capacity, the rate of data sent to each user is reduced to relieve the disk sy... View full abstract»

In this paper, a dynamic addressing scheme (DAVQ) is introduced for image vector quantization. In the proposed system, the dynamic address obtained by two-stage searching will be transmitted instead of the absolute address in conventional VQ systems. Simulation results demonstrate that a significant savings in bit rate is acquired when compared with the standard VQ system View full abstract»