Stored File Format for MPEG-4

H. Kalva, A. Eleftheriadis
Department of Electrical Engineering, Columbia University

A. Puri, R. Schmidt
AT&T Research

Contribution M2062, 39th MPEG Meeting, Bristol, UK, April 1997

Introduction

The MPEG-1 and MPEG-2 standards specify bitstream representations for Audio, Video and Systems. Although they are intended to support interactivity, the flexibilities they offer are rather limited. Among the reasons for these limitations is the lack of a stored file format defined by MPEG. A number of ad hoc and incompatible extensions for file formats are currently in use such as .mpg, m1v, m2v, .m2s etc. Since MPEG-4 offers opportunities for much more flexibility in terms of types of audiovisual objects, editing of objects, composition of objects and user controlled presentation, it seems even more necessary to standardize a flexible and extensible file format. In other words, defining a standardized MPEG-4 file format will facilitate the following:

• Random Access to AV Objects
• Editing of AV Objects - insertion, deletion, modification
• Random Access to Composition Data
• Editing of Composition Data
• Unified representation of MPEG-1, MPEG-2: audio, video and systems data files, and coded MPEG-4 data