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/**
* @class dash::mpd::IDescriptor
* @brief This interface is needed for accessing the attributes of the <tt><b>Descriptor</b></tt> type as specified in <em>ISO/IEC 23009-1, Part 1, 2012</em>, section 5.8.2, table 21
* @details The MPD may contain descriptors that make use of a common syntax as defined in this subclause.
* The elements of type \c DescriptorType provide a flexible mechanism for DASH content authors to annotate
* and extend the \c <b>MPD</b>, \c <b>Period</b>, \c <b>AdaptationSet</b> and \c <b>Representation</b> elements.\n
* The descriptor elements are all structured in the same way, namely they contain a \c \@schemeIdUri attribute that provides a URI to identify the scheme and
* an optional attribute \c \@value. The semantics of the element are specific to the scheme employed. The URI identifying the scheme may be a URN or a URL.\n
* In <em>ISO/IEC 23009-1, Part 1, 2012</em>, specific elements for descriptors are defined in section 5.8.4.\n
* The MPD does not provide any specific information on how to use these elements. It is up to the application that employs DASH formats
* to instantiate the description elements with appropriate scheme information. However, this part of ISO/IEC 23009 defines some specific schemes in 5.8.5.\n
* DASH applications that use one of these elements must first define a Scheme Identifier in the form of a URI and must then define the value space
* for the element when that Scheme Identifier is used. The Scheme Identifier appears in the \c \@schemeIdUri attribute.
* In the case that a simple set of enumerated values are required, a text string may be defined for each value and this string must be included
* in the \c \@value attribute. If structured data is required then any extension element or attribute may be defined in a separate namespace.\n
* Two elements of type DescriptorType are equivalent, if the element name, the value of the \c \@schemeIdUri and the value of the \c \@value attribute are equivalent.
* If the \c \@schemeIdUri is a URN, then equivalence shall refer to lexical equivalence as defined in clause 5 of RFC 2141. If the \c \@schemeIdUri is a URL,
* then equivalence shall refer to equality on a character-for-character basis as defined in clause 6.2.1 of RFC3986.
* If the \c \@value attribute is not present, equivalence is determined by the equivalence for \c \@schemeIdUri only.
* Attributes and element in extension namespaces are not used for determining equivalence.
* @see dash::mpd::IMPDElement
*
* @author bitmovin Softwareentwicklung OG \n
* Email: libdash-dev@vicky.bitmovin.net
* @version 2.1
* @date 2013
* @copyright bitmovin Softwareentwicklung OG, All Rights Reserved \n\n
* This source code and its use and distribution, is subject to the terms
* and conditions of the applicable license agreement.
*/
#ifndef IDESCRIPTOR_H_
#define IDESCRIPTOR_H_
#include "config.h"
#include "IMPDElement.h"
namespace dash
{
namespace mpd
{
class IDescriptor : public virtual IMPDElement
{
public:
virtual ~IDescriptor(){}
/**
* Returns a reference to a string that specifies a URI to identify the scheme. \n
* The semantics of this element are specific to the scheme specified by this attribute.
* The \c \@schemeIdUri may be a URN or URL. When a URL is used, it should also contain a month-date in the form
* mmyyyy; the assignment of the URL must have been authorized by the owner of the domain name in that URL on
* or very close to that date, to avoid problems when domain names change ownership.
* @return a reference to a string
*/
virtual const std::string& GetSchemeIdUri () const = 0;
/**
* Returns a reference to a string that specifies the value for the descriptor element. \n
* The value space and semantics must be defined by the owners of the scheme identified in the \c \@schemeIdUri attribute.
* @return a reference to a string
*/
virtual const std::string& GetValue () const = 0;
};
}
}
#endif /* IDESCRIPTOR_H_ */
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