An IPTC metadatum ("dataset"), consisting of an IptcKey and a Value and methods to manipulate these. More...

#include <iptc.hpp>

Inheritance diagram for Exiv2::Iptcdatum:

Public Member Functions
Creators
	Iptcdatum (const IptcKey &key, const Value *pValue=nullptr)
	Constructor for new tags created by an application. The Iptcdatum is created from a key / value pair. Iptcdatum copies (clones) the value if one is provided. Alternatively, a program can create an 'empty' Iptcdatum with only a key and set the value using setValue(). More...

	Iptcdatum (const Iptcdatum &rhs)
	Copy constructor.

	~Iptcdatum () override=default
	Destructor.

Manipulators
Iptcdatum &	operator= (const Iptcdatum &rhs)
	Assignment operator.

Iptcdatum &	operator= (const uint16_t &value)
	Assign value to the Iptcdatum. The type of the new Value is set to UShortValue.

Iptcdatum &	operator= (const std::string &value)
	Assign value to the Iptcdatum. Calls setValue(const std::string&).

Iptcdatum &	operator= (const Value &value)
	Assign value to the Iptcdatum. Calls setValue(const Value*).

void	setValue (const Value *pValue) override
	Set the value. This method copies (clones) the value pointed to by pValue.

int	setValue (const std::string &value) override
	Set the value to the string value, using Value::read(const std::string&). If the Iptcdatum does not have a Value yet, then a Value of the correct type for this Iptcdatum is created. If that fails (because of an unknown dataset), a StringValue is created. Return 0 if the value was read successfully.

Public Member Functions inherited from Exiv2::Metadatum
virtual	~Metadatum ()=default
	Destructor.

std::string	print (const ExifData *pMetadata=nullptr) const
	Write the interpreted value to a string. More...

uint32_t	toUint32 (size_t n=0) const
	Return the n-th component of the value converted to uint32_t.

Accessors
size_t	copy (byte *buf, ByteOrder byteOrder) const override
	Write value to a data buffer and return the number of bytes written. More...

std::ostream &	write (std::ostream &os, const ExifData *pMetadata=nullptr) const override
	Write the interpreted value to an output stream, return the stream. More...

std::string	key () const override
	Return the key of the Iptcdatum. The key is of the form 'Iptc.recordName.datasetName'. Note however that the key is not necessarily unique, i.e., an IptcData object may contain multiple metadata with the same key.

std::string	recordName () const
	Return the name of the record (deprecated) More...

uint16_t	record () const
	Return the record id. More...

const char *	familyName () const override
	Return the name of the metadata family (which is also the first part of the key)

std::string	groupName () const override
	Return the name of the metadata group (which is also the second part of the key)

std::string	tagName () const override
	Return the name of the tag (aka dataset) More...

std::string	tagLabel () const override
	Return a label for the tag.

std::string	tagDesc () const override
	Return a description for the tag.

uint16_t	tag () const override
	Return the tag (aka dataset) number.

TypeId	typeId () const override
	Return the type id of the value.

const char *	typeName () const override
	Return the name of the type.

size_t	typeSize () const override
	Return the size in bytes of one component of this type.

size_t	count () const override
	Return the number of components in the value.

size_t	size () const override
	Return the size of the value in bytes.

std::string	toString () const override
	Return the value as a string.

std::string	toString (size_t n) const override
	Return the n-th component of the value converted to a string. The behaviour of the method is undefined if there is no n-th component.

int64_t	toInt64 (size_t n=0) const override
	Return the n-th component of the value converted to int64_t. The return value is -1 if the value is not set and the behaviour of the method is undefined if there is no n-th component.

float	toFloat (size_t n=0) const override
	Return the n-th component of the value converted to float. The return value is -1 if the value is not set and the behaviour of the method is undefined if there is no n-th component.

Rational	toRational (size_t n=0) const override
	Return the n-th component of the value converted to Rational. The return value is -1/1 if the value is not set and the behaviour of the method is undefined if there is no n-th component.

Value::UniquePtr	getValue () const override
	Return an auto-pointer to a copy (clone) of the value. The caller owns this copy and the auto-poiner ensures that it will be deleted. More...

const Value &	value () const override
	Return a constant reference to the value. More...

Additional Inherited Members
Protected Member Functions inherited from Exiv2::Metadatum
Metadatum &	operator= (const Metadatum &)=default
	Assignment operator. Protected so that it can only be used by subclasses but not directly.

	Metadatum ()=default

	Metadatum (const Metadatum &)=default

Detailed Description

An IPTC metadatum ("dataset"), consisting of an IptcKey and a Value and methods to manipulate these.

This is referred in the standard as a property.

Constructor & Destructor Documentation

◆ Iptcdatum()

Exiv2::Iptcdatum::Iptcdatum	(	const IptcKey &	key,
		const Value *	pValue = `nullptr`
	)

explicit

Constructor for new tags created by an application. The Iptcdatum is created from a key / value pair. Iptcdatum copies (clones) the value if one is provided. Alternatively, a program can create an 'empty' Iptcdatum with only a key and set the value using setValue().

Parameters

key	The key of the Iptcdatum.
pValue	Pointer to a Iptcdatum value.

Exceptions

Error if the key cannot be parsed and converted to a tag number and record id.

Member Function Documentation

◆ copy()

size_t Exiv2::Iptcdatum::copy	(	byte *	buf,
		ByteOrder	byteOrder
	)		const

overridevirtual

Write value to a data buffer and return the number of bytes written.

The user must ensure that the buffer has enough memory. Otherwise the call results in undefined behaviour.

Parameters

buf	Data buffer to write to.
byteOrder	Applicable byte order (little or big endian).

Returns: Number of characters written.

Implements Exiv2::Metadatum.

◆ getValue()

Value::UniquePtr Exiv2::Iptcdatum::getValue ( ) const

overridevirtual

Return an auto-pointer to a copy (clone) of the value. The caller owns this copy and the auto-poiner ensures that it will be deleted.

This method is provided for users who need full control over the value. A caller may, e.g., downcast the pointer to the appropriate subclass of Value to make use of the interface of the subclass to set or modify its contents.

Returns: An auto-pointer containing a pointer to a copy (clone) of the value, 0 if the value is not set.

Implements Exiv2::Metadatum.

◆ record()

uint16_t Exiv2::Iptcdatum::record ( ) const

Return the record id.

Returns: record id

◆ recordName()

std::string Exiv2::Iptcdatum::recordName ( ) const

Return the name of the record (deprecated)

Returns: record name

◆ tagName()

std::string Exiv2::Iptcdatum::tagName ( ) const

overridevirtual

Return the name of the tag (aka dataset)

Returns: tag name

Implements Exiv2::Metadatum.

◆ value()

const Value& Exiv2::Iptcdatum::value ( ) const

overridevirtual

Return a constant reference to the value.

This method is provided mostly for convenient and versatile output of the value which can (to some extent) be formatted through standard stream manipulators. Do not attempt to write to the value through this reference. An Error is thrown if the value is not set; as an alternative to catching it, one can use count() to check if there is any data before calling this method.

Returns: A constant reference to the value.

Exceptions

Error if the value is not set.

Implements Exiv2::Metadatum.

◆ write()

std::ostream& Exiv2::Iptcdatum::write	(	std::ostream &	os,
		const ExifData *	pMetadata = `nullptr`
	)		const

overridevirtual

Write the interpreted value to an output stream, return the stream.

The method takes an optional pointer to a metadata container. Pretty-print functions may use that to refer to other metadata as it is sometimes not sufficient to know only the value of the metadatum that should be interpreted. Thus, it is advisable to always call this method with a pointer to the metadata container if possible.

This functionality is currently only implemented for Exif tags. The pointer is ignored when used to write IPTC datasets or XMP properties.

Without the optional metadata pointer, you do not usually have to use this function; it is used for the implementation of the output operator for Metadatum, operator<<(std::ostream &os, const Metadatum &md).

See also print(), which prints the interpreted value to a string.

Implements Exiv2::Metadatum.

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

iptc.hpp

Public Member Functions

Accessors

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ Iptcdatum()

Member Function Documentation

◆ copy()

◆ getValue()

◆ record()

◆ recordName()

◆ tagName()

◆ value()

◆ write()