TV Metadata Interoperability

Media houses use a wide variety of mostly non-standardised metadata formats for their workflows and archives. Consequently, when interconnecting metadata systems from different origin, time-consuming data mappings are required to cope with the more or less incompatible metadata schemes that are, for example, used by the providing and the consuming components. A solution to the problem is to apply a unified metadata exchange format that supports quick transformation of metadata with only one adaptation to the exchange model instead of connecting the many systems involved using point-to-point mappings.

Why was this of interest to NoTube?

NoTube aimed at bringing together the TV and the web world. The TV metadata used in the project’s use cases came from different professional sources and hence in different formats. They needed to be aligned to a persistent metadata format used by NoTube. Furthermore, NoTube explored the use of unified metadata exchange formats as convenient input interfaces e.g. for legacy systems.

The following video was produced in the project to illustrate the situation in NoTube.

What NoTube has done in this area

After analysing the requirements of the NoTube Use Cases, TV-Anytime was identified as persistent internal metadata format. At the time being, TV-Anytime it is the only standardised format used in consumer electronic (CE) devices such as Set Top Boxes, Personal Video Recorders etc. A detailed description of the analysis of the metadata formats and the Use Case requirements can be found in the NoTube deliverable D2.1 Requirements Analysis.

Based on the requirements established by the use cases, metadata transformation services were developed to realise the scenario depicted in the Figure below. For the use case “Personalized Semantic News”, the mapping between the PrestoSpace metadata model and TV-Anytime was developed and implemented in several software components. In order to be future proof, the professional Broadcast Metadata Exchange Format (BMF) was chosen as interface between the NoTube platform and external broadcast sources. Consequently, the mapping process for the PrestoSpace metadata is done in two steps: First comes the transformation from PrestoSpace to BMF and in a second step the transformation from BMF to TV-Anytime. These two transformations were implemented as separate software modules which are used by appropriate services inside the NoTube platform. Note that other metadata systems can easily be added to this universal translation concept. As an example, the Figure below lists the FESAD model that is widely used by German broadcasters.

As professional input format for advertisement descriptions for the use case “Personalized TV Guide with Adaptive Advertising” egtaMETA has been selected. egtaMETA is a metadata schema for business-to-business file-based exchange of advertising material developed jointly by EBU and egta. To transfer this information to the internal NoTube format the mapping between egtaMETA and TV-Anytime was specified and implemented in an appropriate software component. This component is intended to be used by a service to integrate the transformation inside the NoTube platform.

For details about the metadata mappings see deliverable D2.2 Metadata Conversion Concept and Prototype Implementation. The developed services are described in D2.3 Metadata Conversion Concept and Prototype Implementation. The PrestoSpace 2BMF and BMF2TVA conversion services are accessible here. For the egtaMETA2TVA service click here.

An essential requirement of the use case Personalised Semantic News was the CRUD (Created, Read, Update and Delete) functionality. This functionality was implemented and provided to enable applications of this use case to retrieve and manipulate metadata objects in their own internal format (i.e. RAI-NIC) without the need for knowing the TV-Anytime format.

It was also an essential issue to ensure the quality of the conversions regarding data consistency. During the evaluation phases in the project, we assessed the quality of the metadata conversions that were developed according to the requirements of the Use Case partners. Even though the different formats used in the conversions support, in principle, the same information, some issues occurred. Some of them could be solved by adequate modifications of the conversions; others could only be solved by using very specific metadata mappings to transport information that would otherwise be lost in the transformation process. Especially the conversion of metadata from the PrestoSpace format via BMF and TV-Anytime to the RAI-NIC format showed this problem (see D2.4 Validation and Testing Report for details).

When the project started in 2009, semantic applications were not really a topic for most broadcasters, yet. Today, there is more awareness for semantic web applications in broadcasting, not least thanks to NoTube (see http://www.slideshare.net/laroyo/notube-project-presentation-ibc2010). Thus, the NoTube partner IRT decided to provide BMF metadata also in a standard Semantic Web format. BMF is designed for metadata exchange in the media production area, but also useful for applications related to program distribution since it covers rich production metadata. Semantic Web standards can provide access to the semantics of BMF metadata, so we first created a BMF OWL ontology based on the BMF model. The BMF XML data is translated to BMF RDF using this ontology. RDF provides mechanisms to link to external data sets like DBpedia (see Figure below).

Summary

The reason for the selection of a central metadata model in the NoTube platform was to ensure easy integration of other components that provide or consume metadata. It was also required to use existing metadata formats instead of developing new formats which often is the case. So, TV-Anytime was selected and agreed upon by all partners for being the format to be used to provide metadata required by the content consumers.

In order to provide a similar “metadata interface” for metadata coming in formats used in the professional media production, we decided to add BMF as additional intermediate format in the metadata conversion for news related metadata. However, the number of metadata formats that were finally used for the realisation within the NoTube demonstrators was too limited that the benefits of the selected approach could have been shown experimentally. Nevertheless, BMF proved its ability as universal metadata exchange format.

All in all, TV-Anytime has proven to be a powerful and comprehensive metadata format for the exchange of information related to the distribution of TV content to the end-users. TV-Anytime allows for carrying all information required for innovative non-linear distribution of TV content as it was developed in the NoTube Showcases. Furthermore, requirements that result from the evaluation and that concern the necessary extension of the used metadata formats, were collected and reflected into the responsible developer communities and standardisation bodies.

Find out more: See the Things to use section of this site

Who was involved? Institut fuer Rundfunktechnik (IRT) and Thomson Video Networks with Polymedia and The Open University in collaboration with other project partners.

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