Exiv2::XmpProperties Class Reference

XMP property reference, implemented as a static class. More...

#include <properties.hpp>

Public Types
using	NsRegistry = std::map< std::string, XmpNsInfo >
	Type for the namespace registry.

Static Public Member Functions
static const char *	propertyTitle (const XmpKey &key)
	Return the title (label) of the property.
static const char *	propertyDesc (const XmpKey &key)
	Return the description of the property.
static TypeId	propertyType (const XmpKey &key)
	Return the type for property key. The default for unknown keys is xmpText.
static const XmpPropertyInfo *	propertyInfo (const XmpKey &key)
	Return information for the property for key.
static std::string	ns (const std::string &prefix)
	Return the namespace name for the schema associated with prefix.
static const char *	nsDesc (const std::string &prefix)
	Return the namespace description for the schema associated with prefix.
static const XmpPropertyInfo *	propertyList (const std::string &prefix)
	Return read-only list of built-in properties for prefix.
static const XmpNsInfo *	nsInfo (const std::string &prefix)
	Return information about a schema namespace for prefix. Always returns a valid pointer.
static std::string	prefix (const std::string &ns)
	Return the (preferred) prefix for schema namespace ns.
static void	printProperties (std::ostream &os, const std::string &prefix)
	Print a list of properties of a schema namespace to output stream os.
static std::ostream &	printProperty (std::ostream &os, const std::string &key, const Value &value)
	Interpret and print the value of an XMP property.
static void	registerNs (const std::string &ns, const std::string &prefix)
	Register namespace ns with preferred prefix prefix.
static void	unregisterNs (const std::string &ns)
	Unregister a custom namespace ns.
static void	unregisterNs ()
	Unregister all custom namespaces.
static const XmpNsInfo *	lookupNsRegistry (const XmpNsInfo::Prefix &prefix)
	Get the registered namespace for a specific prefix from the registry.
static void	registeredNamespaces (Exiv2::Dictionary &nsDict)
	Get all registered namespaces (for both Exiv2 and XMPsdk)

Static Public Attributes
static std::mutex	mutex_
	Lock to be used while modifying properties.
static NsRegistry	nsRegistry_
	Namespace registry.

Detailed Description

XMP property reference, implemented as a static class.

Member Function Documentation

ns()

static std::string Exiv2::XmpProperties::ns ( const std::string &  prefix )

static

Return the namespace name for the schema associated with prefix.

Parameters

prefix

Prefix

Returns

The namespace name

Exceptions

Error

if no namespace is registered with prefix.

nsDesc()

static const char * Exiv2::XmpProperties::nsDesc ( const std::string &  prefix )

static

Return the namespace description for the schema associated with prefix.

Parameters

prefix

Prefix

Returns

The namespace description

Exceptions

Error

if no namespace is registered with prefix.

nsInfo()

static const XmpNsInfo * Exiv2::XmpProperties::nsInfo ( const std::string &  prefix )

static

Return information about a schema namespace for prefix. Always returns a valid pointer.

Parameters

prefix

The prefix

Returns

A pointer to the related information

Exceptions

Error

if no namespace is registered with prefix.

prefix()

static std::string Exiv2::XmpProperties::prefix ( const std::string &  ns )

static

Return the (preferred) prefix for schema namespace ns.

Parameters

ns	Schema namespace

Returns

The prefix or an empty string if namespace ns is not registered.

propertyDesc()

static const char * Exiv2::XmpProperties::propertyDesc ( const XmpKey &  key )

static

Return the description of the property.

Parameters

key	The property key

Returns

The description of the property, 0 if the key is of an unknown property.

propertyInfo()

static const XmpPropertyInfo * Exiv2::XmpProperties::propertyInfo ( const XmpKey &  key )

static

Return information for the property for key.

If the key is a path to a nested property (one which contains a slash, like Xmp.MP.RegionInfo/MPRI:Regions), determines the innermost element (Xmp.MPRI.Regions) and returns its property information.

Parameters

key	The property key

Returns

A pointer to the property information, 0 if the key is of an unknown property.

propertyList()

static const XmpPropertyInfo * Exiv2::XmpProperties::propertyList ( const std::string &  prefix )

static

Return read-only list of built-in properties for prefix.

Parameters

prefix

Prefix

Returns

Pointer to the built-in properties for prefix, may be 0 if none is configured in the namespace info.

Exceptions

Error

if no namespace is registered with prefix.

propertyTitle()

static const char * Exiv2::XmpProperties::propertyTitle ( const XmpKey &  key )

static

Return the title (label) of the property.

Parameters

key	The property key

Returns

The title (label) of the property, 0 if the key is of an unknown property.

propertyType()

static TypeId Exiv2::XmpProperties::propertyType ( const XmpKey &  key )

static

Return the type for property key. The default for unknown keys is xmpText.

Parameters

key	The property key

Returns

The type of the property

registerNs()

static void Exiv2::XmpProperties::registerNs ( const std::string &  ns, const std::string &  prefix  )

static

Register namespace ns with preferred prefix prefix.

If the prefix is a known or previously registered prefix, the corresponding namespace URI is overwritten.

Note

This invalidates XMP keys generated with the previous prefix.

Examples

xmpsample.cpp.

unregisterNs() [1/2]

static void Exiv2::XmpProperties::unregisterNs ( )

static

Unregister all custom namespaces.

The function only unregisters namespaces registered earlier, it does not unregister built-in namespaces.

Note

This invalidates XMP keys generated in any custom namespace.

unregisterNs() [2/2]

static void Exiv2::XmpProperties::unregisterNs ( const std::string &  ns )

static

Unregister a custom namespace ns.

The function only has an effect if there is a namespace ns registered earlier, it does not unregister built-in namespaces.

Note

This invalidates XMP keys generated in this namespace.

Member Data Documentation

mutex_

std::mutex Exiv2::XmpProperties::mutex_

static

Lock to be used while modifying properties.

Todo:

For a proper read-write lock, this shall be improved by a std::shared_timed_mutex (once C++14 is allowed) or std::shared_mutex (once C++17 is allowed). The read-access locks shall be updated to std::shared_lock then.

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The documentation for this class was generated from the following file:

• properties.hpp