INTERNATIONAL ORGANISATION FOR STANDARDISATION

ORGANISATION INTERNATIONALE DE NORMALISATION

ISO/IEC JTC1/SC29/WG11

CODING OF MOVING PICTURES AND AUDIO

ISO/IEC JTC1/SC29/WG11/N9694

Antalya, January 2008

Title:	Requirements on Professional Archival Application Format

Source:	Systems Subgroup

Status:	Approved

Introduction

Digital contents in many different forms are now being created all over the world. There is a need to archive or preserve such valuable contents in a cost efficient manner while making them fully accessible in their original form even long time after their creation date. Definition of a digital archival format for such content is of a central importance to digital archiving systems. In addition, it is obvious that such an archival format should also enable cost efficient and convenient transfer of digital data.

The Professional Archival Application Format (PA-AF) aims at offering a standardized solution which enables sustainability, accessibility and playability of such digital content, making full use of MPEG tools for maximum interoperability. It offers a standardized way how to use MPEG-21 file format and combination of metadata from MPEG-7 and MPEG-21 technologies for the archival application domain.

This document provides the summary of requirements of the PA-AF derived from the responses of the Call for Requirements [1-5].

Scope of Professional Archival Application Format

The purpose of the Professional Archival Application Format (PA-AF) is to provide a standardized packaging format. This packaging format can also serve as an implementation of the archival reference model specified by the Open Archival Information System (OAIS) [6]. The OAIS Reference Model is a framework for understanding and applying concepts necessary for long-term digital information (where long-term is long enough to be concerned about changing technologies). In addition, the PA-AF can also be used as an intermediate or exchange packaging format for any kind of multimedia content.

The action of archiving digital multimedia content may include processes starting from creation, delivery to the archival system, and dissemination to consumers. The PA-AF specifies the digital archive produced by the archiving process. The PA-AF does not specify how the content is created. The PA-AF does not specify any agreement of how the content should be handled and delivered to the archival system. The PA-AF assumes that the content to be packed into the PA-AF archive is available in an appropriate digital format. The PA-AF also does not specify how the content is disseminated to the consumer as the extracted content from a PA-AF archive is exactly in the format that was input to the PA-AF archive.

The PA-AF specifies the file format for carriage of digital multimedia content, metadata to describe context information related to digital multimedia content stored in the archive, metadata to describe the logical structure of how the digital multimedia content is stored in the archive, identification of processing tools that are applied to the digital multimedia content as pre-processing treatment before they are stored in the archive, as well as data protection and integrity tools, data governance tools, and data compression tools.

Overview of Professional Archival Application Format

In order to create a general application format which can be applied as an archiving application, common requirements are extracted and specified.

Fig.1 shows the scope of the PA-AF specification. The PA-AF shall standardize technologies for packaging multimedia files, metadata for content description of files in the PA-AF container, and metadata for identification of tools that are used in the pre-processing phase (i.e., lossless compression tool description, governance and protection description, etc). PA-AF does not preclude any technologies required to meet more specific application scenarios tailored to the need of users (e.g., dissemination of archive content).

Fig.1: Scope of the Professional Archival Application Format.

Requirements

The technical requirements shall be extracted and specified as follows:

Requirement	Notes
A: Packaging	A01	Packaging format of PA-AF should be able to serve as implementation of the information package defined in the OAIS reference model.
A02	PA-AF should pack files and folder structures into single archive.
A03	PA-AF should support large files exceeding 4GB.
A04	PA-AF should support a mechanism to allow the splitting of large archive files into several smaller archive files without loss of information.
A05	PA-AF should be able to pack any kind of files including Audio, Video, Images, Metadata files and any other files.	The types of files should be stored in an archive and should not be stored in an archive shall be controlled by the policy.
A06	PA-AF should preserve the original file names, attributes, and the folder structure.
A07	PA-AF shall support perfect extraction of archive into its original form.
A08	Files output from extraction of an archive shall have the same directory structure as that of input files.
A09	It shall be possible to un-pack an archived file losslessly, which means complete reconstruction of original files, including the filenames, folder structures, and attributes of those files or folders.
A10	Files outputted from extraction of an archive shall be the bit-for-bit same as the original input files.
A11	PA-AF shall support extraction of all files in the archive.
A12	PA-AF shall support extraction of single file out of collection of files in archive.
A13	PA-AF shall support browsing of archived files without having to extract the files out of the archive.
B: Cross-platform operation	B01	PA-AF should support cross-platform operation, such as Windows, Mac, and Linux platforms.
B02	The cross-platform support should include interoperability among different file-systems (file attributes) and character-sets.
C: Compression	C01	PA-AF itself shall be compression scheme independent.
C02	PA-AF should compress archive’s input files.
C03	If any compression scheme is used, PA-AF shall use lossless compression algorithm.
C04	PA-AF shall allow different compression algorithm for different data type. (e.g., MPEG-4 ALS for audio data type, JPEG2000LS for image data type, ZIP compression scheme for text data type)
C05	PA-AF shall allow the use of one or more compression algorithms for file with composite data type.
D: Meta-information	D01	PA-AF should support association of richer information about files in the archive.
D02	PA-AF should provide context information about the content in the archive and the archive file itself.
D03	PA-AF should provide creation context information.
D04	PA-AF should provide content profile information.
D05	PA-AF should provide access and/or modification history of the archive.
D06	PA-AF shall provide mechanism to accommodate application specific context information.
D07	PA-AF should provide Modality information of the content (ex., text, image, audio, video, graphics, etc).
D08	PA-AF should provide File format information of the content (ex., MP3 audio, AAC audio, MP4 video, JPEG image, GIF image, etc).
D09	PA-AF should provide Resolution information of the content (ex., bitrate, spatial resolution, temporal resolution, etc).
E: Identification	E01	PA-AF should have any mechanism to detect a type of the file stored in the Professional Archival AF file
E02	There shall be a mechanism to provide unique and unambiguous identification of each digital element.
G: DRM	G01	PA-AF should support inclusion of Digital rights management (DRM) information for trusted exchange of an archive among rights holders, intermediaries, and users.
G02	PA-AF should support governance of archive usage and distribution.
G03	There should be a mechanism to store licensing and intellectual property rights information for each item.
G04	A mechanism should be available to allow fine grained access control to all data items (essence, metadata, administrative data) in the archive system.
G05	PA-AF should protect individual files and file structures at various levels of granularity including the entire archive.
G06	It should support a simple passwords-lock-encryption mechanism for the Professional Archival AF file.
G07	PA-AF should support detection of post-creation content tampering.
G08	PA-AF should support validation of the Professional Archival AF file.
G09	PA-AF should support a mechanism for identifying the encapsulated DRM system.

References

[1] ISO/IEC JTC1/SC29/WG11/N9165, "Call for Requirements for Professional Archival Multimedia Application Format," 81st MPEG Meeting, Lausanne, July 2007.

[2] ISO/IEC JTC1/SC29/WG11/m14943, "Response to CfR of Professional Archival MAF," 82nd MPEG Meeting, Shenzhen, October 2007.

[3] ISO/IEC JTC1/SC29/WG11/m14954, "Response to Call for Requirements on Professional Archival MAF," 82nd MPEG Meeting, Shenzhen, October 2007.

[4] ISO/IEC JTC1/SC29/WG11/m14786, "Liaison Statement from SC29/WG1 to WG11 on Film Archive Applications [SC29/WG1 N4315]," 82nd MPEG Meeting, Shenzhen, October 2007.

[5] ISO/IEC JTC1/SC29/WG11/N9392, "Requirements on Professional Archival Application Format," 82nd MPEG Meeting, Shenzhen, October 2007.

[6] ISO 14721:2003, "Space data and information transfer systems – Open archival information system – Reference model," 2003.

2	© ISO/IEC 2008 – All rights reserved

© ISO/IEC 2008 – All rights reserved	3

© ISO/IEC 2008 – All rights reserved	1

Text of ISO/IEC 14496-3:2005/PDAM 8 MP4FF Box for Original Audio File Information

Noboru Harada

2008-01-18

NTT