TBM Standards, Specifications, Identifiers, and Data Models etc Identified

Transcription

1 TBM Standards, Specifications, Identifiers, and Data Models etc Identified MPEG & METS EBU (European Broadcasting Union) AudioMD and VideoMD Identifiers SMEF Simple Application Profile combining Dublin Core and MPEG SMIL (Synchronous Multimedia Integration Language) JISC-SURF StreamTeam Partners JISC ARCHES Project... 8 TBM Standards, Specifications, Identifiers, and Data Models etc Identified Expert input to the project has so far helped to identify the following as relevant to the TBM media domain. This working document provides some background information on the reference material, and attempts to make suggestions & seek further information on what way these identified standards, specification, identifiers, data models may be relevant to the Purpose Statement for the Time-based Media Application Profile project and in what way the references could perhaps be usefully accommodated, or otherwise. The document also supports an attempt to come to some conclusions around related questions posed in the Functional Requirements. We would seek to constrain rather than to add, but not at the expense of rendering the subsequent work non-functional or severely restricting the usefulness of the profile. FRBR and Dublin Core are not described here in their own right as they are generic to the profile development projects, and this material is to determine what TBM specific input might be required and how it may be handled. The purpose behind ongoing investigations is to understand the various motives behind existing TBM metadata and standards approaches, their relationship to a Search & Discovery profile and alignment with the existing FR set, rather than to add to the FR or deviate from the development approach the project has been assigned to investigate. This document will be periodically updated to include responses and further information. Relevant resource references will also be posted to the project wiki. Project comments are noted in [RED] Summary List of Ongoing Investigations: TVAnytime, MIX, IPOD spec (for rss container), Wrapper formats (e.g. MXF, Flash, avi, qti), Vocabularies (supply support for but not recommend solutions), OAIS (metadata roles). TBMAP v1.0 June

2 1. MPEG & METS There is a nice summary tutorial on the five MPEG ISO standards (MPEG1, MPEG2, MPEG4, MPEG7, and MPEG21) by Larry Bouthillier February 18, 2004 at: In short, the standards are not sequentially numbered and mp3 is not MPEG-3. MPEG1 became an official standard for encoding audio and video in It is the simplest of the MPEG standards, and describes a way to encode audio and video data streams, along with a way to decode them. MPEG2 relates to digital television, designed to scale up to broadcast and high-definition quality and operating requirements. MPEG4 is designed to scale down to dial-up internet bandwidths, cell phones and PDAs while remaining viable for high-quality desktop streaming, allowing synchronisation of all kinds of media objects with standard interfaces to allow plugging in a DRM scheme. MPEG7 (Multimedia Content Description Interface) is about metadata (and is not a video or audio coding scheme or delivery mechanism). MPEG21 is a Multimedia Framework to let content distributors have complete control over content at all parts of the delivery chain and on all kinds of networks and devices, and allow the right item in a file to be played for the user. MPEG21 is still being developed and doesn t appear to make reference to new metadata or profiles so far. MPEG7 describes three profiles: Simple Metadata Profile (SMP) User Description Profile (UDP) Core Description Profile (CDP). These are collected together from the rest of the standard in Part 9 of the 11 parts. Part 11 provides the XML Schemas for the same three MPEG 7 profiles. As a whole, MPEG 7 is contained in ISO/IEC 15398, and part 9 is referred to as ISO/IEC :2005 with part 11 as ISO/IEC :2005. [Will this information be carried with the file, through its format type rather than represented in the profile itself? The AHDS report suggests that a reliance on extraction tools at present is unwise: Sophisticated metadata standards (e.g. MPEG-7, TV-Anytime, SMIL) and container schemas (MPEG-21 and METS) are now available for the archiving of moving image and sound resources. However, manual metadata creation is expensive and, in reality, little file-level metadata is likely to exist separately from the content other than that which can be auto-generated. Few metadata extraction tools currently exist for this purpose and further research and development work is needed in this area. In addition, the archival-oriented element set proposed in this study makes no assumption as to the way the metadata is stored or contained (e.g. MPEG-21 or METS) and does not distinguish between whole or parts by assuming equal application of the element set to any level of granularity (e.g. whole, segment, still). TBMAP v1.0 June

3 Taken from AHDS Digital Moving Images & sound Archiving Study Chapter 7 Metadata Review and Requirements 7.7 Conclusion p81 retrieved from: 0archiving%20final%20version.doc ] 2. EBU (European Broadcasting Union) EBU has a core metadata set for radio archives which is relatively simple and aligns with EBU/SMPTE/AES and Dublin Core. [This is possibly in line with the scope of the project.] P_Meta and its XML Schema provide metadata on common production practices realised through application-based specifications including, taking into particular account the point of view of broadcasters, e.g. programme exchange between broadcasters and possibly between production processes. [As P_Meta is both broadcast industry and production specific, we believe it is out-ofscope of this project.] 3. AudioMD and VideoMD AudioMD Draft data dictionary: AudioMD Draft schema: VideoMD Draft data dictionary: VideoMD Draft schema: These are draft METS extension metadata schema and data dictionaries for audio and video resources respectively. AudioMD contains 37 technical metadata elements for describing an audio object. VideoMD contains 16 technical metadata elements. It has been suggested (p81 AHDS report) that these represent interim measures developed by the Library of Congress Audi-Visual Prototyping Project with little subsequent development. [The project has not yet ascertained the relevance or mapping concepts associated with these approaches, but the elements may possibly be in line with the scope of the project in the same way as EBU core metadata set, and within the caveats of the Metadata.net simple application profile notes.] 4. Identifiers The project scope for identifiers specifies as: In scope: What are the various identifiers and how these could be used with time based media. Out of Scope: Recommendation of a particular identifier solution. TBMAP v1.0 June

4 [At which points will the profile require identifiers? What hooks needed?] SMEF recognises three particular ISO Editorial Identifiers and makes provision for them as attributes. Very basic descriptions are given here: ISAN (International Standard Audio Visual Number, ISO 15706:2002, permanently issued to an audiovisual work and never altered replaced or reused) V-ISAN (Version-ISAN, ISO 20925, registers a version. The first part is an identifier, the second part is registration, resolution and supporting systems. ISRC is used for soundtracks.) ISRC (International Standard Recording Code, unique and permanent identifier for a specific recording that can be encoded permanently into a product. See SMPTE UMID (Unique Material Identifier, specified in SMPTE 330M. Identifies an instance of audiovisual material uniquely, to enable the material instance to be linked with its associated metadata. The extended UMID allows a source pack to be attached which carries data for time, date, geospatial location, etc.) The JISC Standards Catalogue: Identifier Standards (available at: notes the following, along with fuller descriptions and further information: ARK, (Archival Resource Key) COinS (ContextObjects in Spans, a simple, ad hoc community specification for publishing OpenURL references in HTML) DOI (Digital Object Identifier, a permanent identifier given to a networked resource so that if its address changes, users will be redirected to its new address) Handle (a distributed information system for assigning, managing and resolving persistent identifiers) INFO (a Uniform Resource Identifier (URI) scheme created for information assets that have identifiers in public namespaces but that are not part of the URI allocation (e.g. LCCNs) OpenURL (NISO standard Z , the OpenURL Framework for Context-Sensitive Services provides a means of describing a referenced resource along with a description of the context of the reference, known as a ContextObject) PURL (Persistent Uniform Resource Locator) URI (Uniform Resource Identifier, a generic name for any of a class of ways of identifying resources on the Internet) 5. SMEF TBMAP v1.0 June

5 The SMEF data model the BBC s Standard Media Exchange Framework. The Data Model (currently v1.10) is available free-of-charge subject to a specific licence agreement and eventual return of a questionnaire as to how it has been used and what benefits have been derived from its use. SMEF appears to be useful for helping to understand the different technical relationships across time-based media, and as a reference to standards, specifications and identifiers that may be relevant to the project remit. For Dublin Core, SMEF recommends projects use SMEF to establish their information analysis while ensuring DC descriptors are set up at the same time. For HE genres where, for example, production information or televisions attributes, for example, are important to search and discovery, SMEF may help with extending any application profile to better serve such a group. It may also perhaps have some scope as a source for additional elements related to the current project. Certainly, not all of SMEF will be relevant to post-production search & discovery, and what is relevant may not perhaps present in the exact structure as developed here. However, SMEF could be useful more generally to demonstrate how different types and complexities of domain model are relevant for different approaches to the media type, and as a particular view of modelling the TBM world. [Any comment on this analysis?] By way of further information, SMEF is designed to provide a set of definitions for the information required in production, distribution and management of media assets, currently expressed as a data dictionary and set of Entity Relationship Diagrams. It is designed to be comprehensive (the model stretches to 8 pages, and v 1.10 stretches to nearly 400 pages), and is specific to a particular industry sector, although the definitions are designed to be organisation independent. The scope is wide in that the model is based on metadata associated with media essence. It is applicable across television, radio, web and supports both analogue and digital services. The eight sections of SMEF cover: Editorial Objects (e.g. complete programme or item, work, episode) Image Format Type (e.g. geometric characteristics of an image or display device or constraints on the use of the image area) Acquisition Blocks (group of audio items in a published form e.g. CDs or records) Media Objects and Unique Material Instances (description of a component of an editorial object where each media type is a single object e.g. video is one, subtitles another) Location, Story & Classification (summary of how items or programmes can be referenced, classified or catalogued) Transmission and Publication of Editorial Objects (e.g. planned & actual transmission) People & Organisations (e.g. roles in media asset management such as cameraman or rights holder) Programme Production ( commissions, bids, projects etc) TBMAP v1.0 June

6 6. Simple Application Profile combining Dublin Core and MPEG-7 Metadata.Net was maintained until August 2006 by the MAENAD Project of ITEE at the University of Queensland and holds a draft simple combination Application Profile with a mapping between 15 DC elements DC and MPEG-7. The exercise concludes that the mapping is possible but complex and the MPEG-7 Descriptors corresponding to each DC element: are distributed across a range of Description Schemes (DSs); are embedded at a low level within nested XML descriptions; often occur in multiple alternative Description Schemes/contexts. There is often no simple or obvious one-to-one mapping or exact semantic equivalent within MPEG-7 to the Dublin Core elements. Illustrated examples are used to indicate the respective strengths and weaknesses of DC and MPEG-7 noting: Dublin Core provides a relatively simple, light-weight and concise method for resource discovery of composite resources over the Internet. It is not designed to describe the temporal, spatial or spatio-temporal aspects or the visual or audio features associated with multimedia resources. In comparison, MPEG-7 provides a rather heavy-weight approach to describing the creation and classification properties of an audiovisual resource. MPEG-7's strengths lie in its ability to specify detailed media-specific formatting and encoding information, and its fine-grained descriptions of temporal, spatial and spatio-temporal components of audiovisual content and their associated audio and visual features. Rather than duplicating the DC elements within MPEG-7 (by introducing a MPEG-7 Dublin Core Description Scheme) or using programmatic code or XSLT to implement dynamic mappings, we propose a hybrid approach which combines the complementary aspects of the DC and MPEG-7 metadata schemes in an application profile. Providing there is an XML Schema [5-7] representation of each vocabulary, defined in their own domain-specific namespaces [8], then implementors can import elements from both the Dubl n Core and MPEG-7 namespaces and combine them into a single description scheme (or "application profile") capable of supporting both cross-domain (Dubl n Core-based) resource discovery as well as fine-grained, content-based, search, retrieval and presentation of audiovisual content (using MPEG-7). [5] XML Schema Part 0: Primer, W3C Recommendation, 2 May [6] XML Schema Part 1: Structures, W3C Recommendation, 2 May [7] XML Schema Part 2: Datatypes, W3C Recommendation, 2 May [8] Namespaces in XML, W3C Recommendation 14 January, TBMAP v1.0 June

7 [Suggests a DC approach for Search & Discovery of this resource type remains sound and that MPEG-7 may be suitable for augmentation in media specific areas that may be required for some purposes or user group needs.] 7. SMIL (Synchronous Multimedia Integration Language) SMIL (pronounced smile ) is an XML-based language that enables simple authoring of interactive audiovisual presentations for the web, and is typically used for choreographing "rich media" presentations which integrate streaming audio and video with images, text or any other media type. Using a small range of elements it is possible to specify and control the time given resources appear in relation to each other, for example a spoken sentence and an image, or a segment of a video with its transcript. [Although the availability of metadata is relied upon to identify the media being choreographed, SMIL itself is a mechanism to use this information to provide presentation and co-ordination of the media on screen. This makes SMIL itself unlikely to be useful in contributing to a Search & Discovery application profile.] 8. JISC-SURF StreamTeam Partners User Generated Content TRIPLE L Project Dr Jan T. Goldschmeding, VU University Amsterdam, Learning on Screen 2008, York National Science Learning Centre, University of York, March 2008 Also with thanks to Johan Ooman and Sylvia Moes of StreamTeam. Work in the Netherlands related to federated searching for video use in learning engages the concept of collecting other materials alongside video used for learning. This falls closer to the domain of learning objects than TBM and so the RDN/LTSN LOM Application Profile or RLLOMAP has been drawn on. As part of a presentation of RET (Reaching European Teachers) at StreamTeam 2008, a report on investigations into CAM (Contextualised Attention Metadata) was made. CAM is concerned with serving personalised content to teachers, particularly where this can be achieved directly into the learning environment such as a VLE. CAM appears to be metric-based and relate to information concerning use of material after it has been retrieved, and so forming a layer separate from content-based metadata that supports federated searching. The CAM operates to directly support user services and operations by working with user profiles to further customise the federated search results against user specified preferences (e.g. smart rankings, smart recommendations). Examples of CAM concepts include: annotations, task/type information, ratings, social network information, duration of use. The requirement for translation of material was highlighted, noting services such as ATHENA Web which provide translation to English of deposited materials. StreamTeam and RET Jan T Goldschmeding StreamTeam 2008 held at DIVERSE, Inholland university, Haarlem, NL, 1 July TBMAP v1.0 June

8 Athena Web, a video portal and workspace for European audiovisual communication professionals in the areas of science and scientific information, see: [This suggests confirmation of the Functional Requirements of the profile to offer Extensibility for tailoring to genre-specific requirements and added-value services Clarity on which aspects of complex objects are in and out of scope and how those in scope are expected to be handled To assist with identification and retrieval of accessible versions and supporting material in this case different language versions. ] 9. JISC ARCHES Project ARCHES Final Report Version The Arches project was funded by JISC as part of the x4l programme, and used UK LOM Core and VRA Core to develop a profile to service large numbers of visual resources including audio and video treated as learning objects. [This falls closer to the domain of learning objects and suggests that in certain cases a Learning Object-oriented Application Profile may be more suited for TBM material depending on its intended audience, and how the material is packaged. Use of VRA Core and the visual aspects of material handled by the project suggest an overlap with image requirements may also occur in cases where learning objects are being handled.] TBMAP v1.0 June