Carsten Herpel

The MPEG-4 systems and description languages: A way ahead in audio visual information representation

Abstract The state of the standardization of the Systems part of ISO/IEC JTC1/SC29/WG11 (MPEG-4 Systems) as specified early 1997 is presented. First, a rationale and the architecture of the complete Systems are described. Based on the rapid technological advances in software and in hardware, the MPEG-4 Systems provides for a framework for the integration of natural and synthetic streamed and synchronised media. The different fields of interest in Systems are then developed from the description of audiovisual scenes to the definition of the multiplex. The programmability of the standard is described for composition and decompression and the language adopted by MPEG-4 on purpose of syntax description is fully detailed. Finally, a conclusion and the future evolutions of the specifications are presented.

MPEG-4 Systems: Elementary stream management

We describe the elementary stream management (ESM) facilities provided by MPEG-4 Systems. Within the extensive set of tools defined by MPEG-4, the ESM tools play a critical role in joining several building blocks together. ESM provides a dual to the scene description language (BIFS) in that it links the streaming resources of a presentation to the scene. We also describe the synchronization functionality as well as the system decoder model that defines the timing behavior and buffer resource management of MPEG-4 receivers. The paper concludes with considerations on data packaging in underlying delivery layer protocols and a description of the MPEG-4 content access procedure.

MPEG-4 systems: Overview

Abstract This paper gives an overview of Part 1 of ISO/IEC 14496 (MPEG-4 Systems). It first presents the objectives of the MPEG-4 activity. In the MPEG-1 and MPEG-2 standards, “Systems” referred only to overall architecture, multiplexing, and synchronization. In MPEG-4, in addition to these issues, the Systems part encompasses scene description, interactivity, content description, and programmability. The description of the MPEG-4 specification follows, starting from the general architecture up to the description of the individual MPEG-4 Systems tools. Finally, a conclusion describes the future extensions of the specification, as well as a comparison between the solutions provided by MPEG-4 Systems and some alternative technologies.

Adaptation and improvement of CCITT reference model 8 video coding for digital storage media applications

Abstract Digital storage media like CD, CD-ROM, MOD, DAT, etc. open new fields of application, e.g. for storage and retrieval of moving video information for multimedia services. This paper describes a video codec operating at a bit rate supported by these media, focus being on 1.15 Mbits/s for net video. It is based on the hybrid DPCM/DCT scheme of CCITT Reference Model 8 which had been optimized within CCITT Study Group XV for telecommunications applications at bit rates ranging from 64 kbits/s to 2 Mbits/s. New building blocks have been added to implement trick modes and to improve subjective picture quality. Periodic coding of frames in an intraframe mode provides random access and, thus, fast search and reverse playback features. Adapted coder control, zoom and pan compensation, half pel accuracy of local motion vectors, weighting of transform coefficients, and noise reduction in the coding loop are the main components improving subjective picture quality for the wider range of TV applications.