Ø Multimedia Content Description Standard

INTRODUCTION

Multimedia content description standard. Addresses how humans expect to interact with computer systems. Part of ISO. Defines standards for digital audio and video. Primal task to develop a format to play back video and audio in real time from CD. Well known standards – MPEG-1, 2, 4 &7. MPEG-7 focuses on representing information about the content, not the content itself. Main goal to provide a rich set of standardized tools to describe the multimedia content. DIFFERENT VIDEO FORMATS

AVI FORMAT Oldest format in 8086 world. Audio video interlaced. Created by Microsoft. Maximum resolution of 160*120 pixels with a refresh rate of 15 frames per second. Popular as first video editing systems and software appeared that used AVI by default. Examples-Fast’s AV master, Micro/Pinnacle’s DC10 to DC50. Disadvantages : Manufacturers adapted AVI format according to their own requirements, AVI format is subject to additional restrictions under windows 98 which makes professional work at higher resolutions more difficult. APPLE’S FORMAT Created by Macintosh, also used in 8086 based pc’s. Proprietary standard of apple’s Quicktime application. Superior to AVI in functionality and quality.

MJPEG FORMAT Stands for Motion JPEG. Intermediate step between still image and video format.

MPEG FORMATS Most popular standard. Stands for Moving Pictures Expert Group. Platform independent. MPEG-1 Released in 1993. Objective to achieve acceptable frame rates and the best possible image quality for moving images and their sound signals for media with a low band width (1-1.5 M bit/s). Design goal is ability to randomly access a sequence within half a second, without a noticeable loss in quality. For most home user and business applications.

MPEG-2 Released in 1995. Basic structure same as that of MPEG-1. Allows data rate up to 100 M bit/s. Used for TV, video films on DVD-Rom. MPEG-4 Highest video quality possible for extremely low data rate (10 K bit/s to 1 M bit/s). Organization of the image contents into independent objects inorder to process them individually. Used for video transmission over internet.

MPEG-7 Latest MPEG project. Can be used independently of other MPEG standards. MPEG-7 T ECHNICAL ACTIVITIES

Standard for defining features of multimedia content . Users can search, browse and retrieve contents effectively and efficiently. MPEG-7 define a multimedia library of methods and tools. MPEG-7 standardizes:  A set of descriptors (D)  A set of description schemes (DS)  A language that specifies description schemes, the Description Definition Language (DDL)  One or more ways (textual, binary) to encode descriptions ORGANIZATION OF MPEG-7 DESCRIPTION TOOLS Basic elements at lower level: basic data types , mathematical structure , schema tools , linking and media localization tools. Schema tools specifies elements for creating valid MPEG-7 schema instance documents and description fragments. Based on this lower level content description and management elements can be defined. These elements describe content from several view points. Currently five view points:  Creation and production  Media  Usage  Structural aspects  Conceptual aspects Creation and production: Contains media information that describes creation and production of content. Usage: Contains media information related to usage of content. Media: Contains description of storage media. Structural aspects: Contains description of AV content from the viewpoint of its structure. Conceptual aspects: Contains a description of AV content from view point of its conceptual notations. Tools for navigation and access and content organization which addresses organization of content by classification. User interaction: Describes user’s preferences for the consumption of multimedia content and usage history.

MPEG-7 WORKING GROUPS Concentrates on specification of description tools (Descriptors and Description schemes). The base for DDL is XML scheme language. MPEG-7 AUDIO GROUP  Develops a range of description tools ranging from generic audio descriptors to more sophisticated description tools like Timbre.

MPEG-7 VIDEO GROUP  Four groups of description tools: Color ,texture, shape and motion.

MPEG-7 MULTIMEDIA DESCRIPTION SCHEMES GROUP  Develops description tools dealing with generic and audiovisual features.  Mainly deals with content description and content management.

MPEG-7 IMPLEMENTATION STUDIES GROUP  Designing and implementing MPEG-7 reference software (XM). MPEG-7 SYSTEMS GROUP  Develops DDL. MPEG-7 APPLICATION DOMAINS

 Board range of applications.  Ranges from multimedia digital libraries ,broadcast media selection ,multi media editing ,home entertainment devices.  Make web as searchable for multimedia content as it is searchable for text today.  All domains making use of multimedia will benefit from MPEG-7. ADVANTAGES

MPEG standards have been successful in the marketplace. Taking advantage of MPEG-7 expertise. Interoperability: rapid uptake of MPEG-7, as it is built on enabling technologies and standards. Data exchange between subsidiaries. Market potential for MPEG-7 applications. MPEG-7 will enable a new generation of multimedia applications. MPEG-7 tools for killer applications. MPEG-7 intellectual property and management protection. MPEG-7 makes content more valuable. MPEG-7 provides a seamless path towards increasingly intelligent content management systems. CONCLUSION

MPEG-7intended to describe audiovisual information regardless of storage , coding , display ,transmission ,medium ,or technology. Addresses a wide variety of media types. Operate both in real time and non real time environments.

MPEG-7

AYYAPPA DAS M.R. Roll No. 00103015 S7 CSE-A MPEG-7 MULTIMEDIA DESCRIPTION SCHEMES