Interframe Bus Encoding Technique and Architecture for MPEG-4 AVC/H.264 Video Compression

In this paper, we propose an implementation of a data encoder to reduce the switched capacitance on a system bus. Our technique focuses on transferring raw video data for multiple reference frames between off-and on-chip memories in an MPEG-4 AVC/H.264 encoder. This technique is based on entropy coding to minimize bus transition. Existing techniques exploit the correlation between neighboring pixels. In our proposed technique, we exploit pixel correlation between two consecutive frames. Our method achieves a 58% power saving compared to an unencoded bus when transferring pixels on a 32-b off-chip bus with a 15-pF capacitance per wire

Synthetic movies

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1989.Includes bibliographical references (leaves 67-70).by John A. Watlington.M.S

Optimization of the motion estimation for parallel embedded systems in the context of new video standards

15 pagesInternational audienceThe effciency of video compression methods mainly depends on the motion compensation stage, and the design of effcient motion estimation techniques is still an important issue. An highly accurate motion estimation can significantly reduce the bit-rate, but involves a high computational complexity. This is particularly true for new generations of video compression standards, MPEG AVC and HEVC, which involves techniques such as different reference frames, sub-pixel estimation, variable block sizes. In this context, the design of fast motion estimation solutions is necessary, and can concerned two linked aspects: a high quality algorithm and its effcient implementation. This paper summarizes our main contributions in this domain. In particular, we first present the HME (Hierarchical Motion Estimation) technique. It is based on a multi-level refinement process where the motion estimation vectors are first estimated on a sub-sampled image. The multi-levels decomposition provides robust predictions and is particularly suited for variable block sizes motion estimations. The HME method has been integrated in a AVC encoder, and we propose a parallel implementation of this technique, with the motion estimation at pixel level performed by a DSP processor, and the sub-pixel refinement realized in an FPGA. The second technique that we present is called HDS for Hierarchical Diamond Search. It combines the multi-level refinement of HME, with a fast search at pixel-accuracy inspired by the EPZS method. This paper also presents its parallel implementation onto a multi-DSP platform and the its use in the HEVC context

XMovie: Architecture and Implementation of a Distributed Movie System

We describe a system for storing, transmitting and presenting digital movies in a computer network. The hardware used in the system is standard hardware, as found in typical workstations today; no special hardware is required. The movies are shown in windows of the X window system. This allows full integration with the classical components of computer applications such as text, color graphics, menus and icons. The XMovie system has several innovative features: First, it contains a new algorithm for the gradual adaptation of the color lookup table during the presentation of the movie to ensure optimal color quality on low-end workstations. Second, it is a multi-standard system supporting the compression techniques MPEG, H.261, Motion JPEG, and a newly developed extension to the well known Color Cell Compression method. Third, we introduce AdFEC, a new adaptable forward error correction method for our movie transmission protocol

An Integrated Network Architecture for a High Speed Distributed Multimedia System.

Computer communication demands for higher bandwidth and smaller delays are increasing rapidly as the march into the twenty-first century gains momentum. These demands are generated by visualization applications which model complex real time phenomena in visual form, electronic document imaging and manipulation, concurrent engineering, on-line databases and multimedia applications which integrate audio, video and data. The convergence of the computer and video worlds is leading to the emergence of a distributed multimedia environment. This research investigates an integrated approach in the design of a high speed computer-video local area network for a distributed multimedia environment. The initial step in providing multimedia services over computer networks is to ensure bandwidth availability for these services. The bandwidth needs based on traffic generated in a distributed multimedia environment is computationally characterized by a model. This model is applied to the real-time problem of designing a backbone for a distributed multimedia environment at the NASA Classroom of the Future Program. The network incorporates legacy LANs and the latest high speed switching technologies. Performance studies have been conducted with different network topologies for various multimedia application scenarios to establish benchmarks for the operation of the network. In these performance studies it has been observed that network topologies play an important role in ensuring that sufficient bandwidth is available for multimedia traffic. After the implementation of the network and the performance studies, it was found that for true quality of service guarantees, some modifications will have to be made in the multimedia operating systems used in client workstations. These modifications would gather knowledge of the channel between source and destination and reserve resources for multimedia communication based on specified requirements. A scheme for reserving resources in a network consisting legacy LAN and ATM is presented to guarantee quality of service for multimedia applications

Hardware study on the H.264/AVC video stream parser

The video standard H.264/AVC is the latest standard jointly developed in 2003 by the ITUT Video Coding Experts Group (VCEG) and the ISO/IEC Moving Picture Experts Group (MPEG). It is an improvement over previous standards, such as MPEG-1 and MPEG-2, as it aims to be efficient for a wide range of applications and resolutions, including high definition broadcast television and video for mobile devices. Due to the standardization of the formatted bit stream and video decoder many more applications can take advantage of the abstraction this standard provides by implementing a desired video encoder and simply adhering to the bit stream constraints. The increase in application flexibility and variable resolution support results in the need for more sophisticated decoder implementations and hardware designs become a necessity. It is desirable to consider architectures that focus on the first stage of the video decoding process, where all data and parameter information are recovered, to understand how influential the initial step is to the decoding process and how influential various targeting platforms can be. The focus of this thesis is to study the differences between targeting an original video stream parser architecture for a 65nm ASIC (Application Specific Integrated Circuit), as well as an FPGA (Field Programmable Gate Array). Previous works have concentrated on designing parts of the parser and using numerous platforms; however, the comparison of a single architecture targeting different platforms could lead to further insight into the video stream parser. Overall, the ASIC implementations showed higher performance and lower area than the FPGA, with a 60% increase in performance and 6x decrease in area. The results also show the presented design to be a low power architecture, when compared to other research

Distributed multimedia systems

A distributed multimedia system (DMS) is an integrated communication, computing, and information system that enables the processing, management, delivery, and presentation of synchronized multimedia information with quality-of-service guarantees. Multimedia information may include discrete media data, such as text, data, and images, and continuous media data, such as video and audio. Such a system enhances human communications by exploiting both visual and aural senses and provides the ultimate flexibility in work and entertainment, allowing one to collaborate with remote participants, view movies on demand, access on-line digital libraries from the desktop, and so forth. In this paper, we present a technical survey of a DMS. We give an overview of distributed multimedia systems, examine the fundamental concept of digital media, identify the applications, and survey the important enabling technologies.published_or_final_versio