8/13/2019 2.3.2 y 2.4 trad

1/3

2.3.2 Metainformation defined on Phase 2

Phase 2 is thought to be an extension (mainly modular) of the specifications of Phase

1, and it also has many new elements that contribute to the idea to improve the

traditional advertising model. Although it is equally focused in the context of the

audiovisual contents, Phase 2 keeps in mind the repercussions and possibilities of acomplete bidirectional context, with the new distribution mechanisms that come with it.

As it is an extension, it is fundamental to keep the compatibility with everything that is

stated on Phase 1, so that it is not necessary to adapt the descriptions or existing tools

to suit the content of Phase 2. This second Phase simply adds new descriptive

resources and protocols for the representation and exchange of information to make

easier the development of certain services that had not been done on the previous

Phase.

The first element of this extension is the introduction of new types of data to describe

contents and users, as well as the adoption of others imported from the standardMPEG-21 (ISO/IEC 21000-2, 2005) to enable new functionalities. This includes the

definition of new types of data to define new contents (games, applications, web

sites), that belong to the ones that have special interpretations according to the

context (for example, in contexts of education), and in general, any element that makes

it possible to describe other formats of information that can be associated to traditional

audiovisual contents, with the purpose of giving more gratifying experiences.

Regarding the descriptive metainformation, Phase 2 introduces a series of new tools to

encourage the development of services of added value, among which we find:

Tools to create groups of many contents: traditional audiovisual contents,applications, games, web sites These elements are grouped in a package

(Packaging, Cat1), to be consumed together, in a free or synchronized way, or

even according to directives in the package. These directives can be fixed or

depending on the different criteria related to the device or the user. This will be

dealt with on Chapter 6.

Information and procedures to estimate the suitability of each content for each

user (Targeting, Cat6), in a way that new contents can be recommended and

delivered automatically to new users according to their profile (preferences

history of consumption, characteristics of the receptor, singular elements of the

context of consumption), or to make the searching process easier forspectators. This is extended on Chapter 5.

A framework for the processing of commercial ads (Intersitials, Cat6) and their

substitution (live or in reproductions of stored content) according to particular

criteria of each spectator. This will also be dealt with of Chapter 5.

A framework to include discount coupons or promotions (Coupons, Cat6) for

available audiovisual contents (or announced products), mark their existence

and explain how to redeem them. It will also be dealt with on Chapter 5, in

which we will reveal details about this tool.

All of this implies new metainformation tables (or extensions of those defines on Phase

1) that are incorporated in the different categories observable on Figure 2.6. As it has

8/13/2019 2.3.2 y 2.4 trad

2/3

been previously stated, these new tables present a modular, incremental nature, which

does not require rectifications for the systems developed according to Phase 1.

2.4 The transportation of metainformation

Just as we have pointed out, the specifications developed by TV-Anytime make a

detailed description of the structures of information that help implement the univocal

references to the contents, as well as of the metainformation we use to characterize

them. However, the development of the services described on the introduction requires

a whole series of procedures to send the information that TV-Anytime does not make

reference to, which affects, for example, the effective transportation of the

metainformation and the contents, the signalization of changes However, TV-

Anytime requires certain functionalities of these mechanisms.

Although we will make a more detailed approach to this of Chapter 7, we will present a

summary of some interesting ideas to which TV-Anytime makes a contribution.

Requisites for transportation mechanisms

The aim of TV-Anytime is to be completely independent of the transportation

mechanisms used in the network of distribution of contents. It is for this reason that it

does not regulate how the information must reach the recipient, left for the standards

that regulate each distribution mechanism.

However, TV-Anytime describes certain requisites demanded to the transportation

mechanism. In unidirectional contexts, TV-Anytime determines that the transportation

system must give certain information to the upper level services in charge of

implementing the functionalities of TV-Anytime. Among them:

It must transport and deliver the metainformation in an asynchronous way, even

when the delivery is produced through many channels, what must be

transparent for the receiving applications.

It must give a method to find out which kind of TV-Anytime metainformation is

available y how to get it. This includes the resolution tables, seen on Section

2.2, as well as the descriptive metainformation of Section 2.3.

It must present the localizators of the concrete instances of the issued contents.

It must allow the cyclic transmition of TV-Anytime structures, with the frequence

the operator finds convenient for each case.

It must give the necessary elements for the selective actualization of the

different metainformation elements, without inconsistencies, even if some of

them are lost.

Segmentation and delivery of TV-Anytime information

In a unidirectional context, from the operator to the user, there is no returning

communication. Therefore, all the information, including the metainformation, is

transported to the user through the diffusion channel, no matter which one it is. This

information can become an important amount of data, as sometimes descriptions of the

whole programs of many channels for many days may be sent.

8/13/2019 2.3.2 y 2.4 trad

3/3

This is especially relevant in a context like the actual one, in which receptors usually

have a limited capacity of process, which makes the managing of all this amount of

data very difficult. Moreover, this information must be cyclically repeated for it to be

permanently accessible for every receptor that is connected. Because of this, the

bandwidth assigned for the metainformation may be significant, requiring a

compromise between the cost of transportation and the minimum rate of refresh that isestablished.

For dealing with these matters, TV-Anytime defines a series of mechanisms to make

the delivery and processing to describe the contents of metainformation easier. These

tools are put together in a group of processes that can be seen on Figure 2.10, and the

ones in the middle are the only regulated in the TV-Anytime standard.

Fragmentation is a procedure according to which it is possible to decompose a TV-

Anytime document into a series of smaller self-contended and consistent elements,

named fragments. A fragment is the smallest part of a determined description that can

be transmitted independently to a terminal, and must be consistent according to the

following:

It may be actualized independently from the other fragments.

It must be processed independently, no matter the order in which these

fragments are received.

Its decodification and aggregation must lead to a valid description.

In the standard, a series of fragments are defined, among which we may find the

PersonName fragment, ProgramImformation fragment, GroupInformation fragment,

PurchaseInformation fragment or Review fragment. In all of these cases, the names

are clear according to the content: they transport the structure of the information

named in the same way.

The second process, called Codification, allows the efficient delivery (in terms of

bandwith) of metainformation in unidirectional contexts. It consists, basically, of the

delivery of metainformation in a binary format, for which the method BiM has been

chosen (ISO/IEC 15938-1, 2002), defined on MPEG-7, mainly due to inoperability.

The different codified fragments are transported (individually or grouped) in a structure

of container designed especially in the TV-Anytime standard.

In the third place, the Encapsulation is a mechanism that makes it possible to know the

identifiers and version numbers of the fragments transported by a container without the

need of opening it and analyzing them individually. This declaration of identifiers and

version numbers enables a simple enquiry to the receptor to monitor the actualizations

made in the containers.

At last, the Indexation is a mechanism to enable the processing of large flows of

fragments in receptors with fewer resources. Receiving an adequate indexation

information enables them to localize easily the wanted information within descriptions

of great seize.