exif-content.h File Reference

#include <libexif/exif-tag.h>
#include <libexif/exif-entry.h>
#include <libexif/exif-data.h>
#include <libexif/exif-log.h>
#include <libexif/exif-mem.h>

Go to the source code of this file.

Data Structures
struct	_ExifContent
Defines
#define	exif_content_get_value(c, t, v, m)
	Return a textual representation of the EXIF data for a tag.
Typedefs
typedef struct _ExifContent	ExifContent
	Holds all EXIF tags in a single IFD.
typedef struct _ExifContentPrivate	ExifContentPrivate
typedef void(*	ExifContentForeachEntryFunc )(ExifEntry *, void *user_data)
Functions
ExifContent *	exif_content_new (void)
ExifContent *	exif_content_new_mem (ExifMem *)
void	exif_content_ref (ExifContent *content)
void	exif_content_unref (ExifContent *content)
void	exif_content_free (ExifContent *content)
void	exif_content_add_entry (ExifContent *c, ExifEntry *entry)
	Add an EXIF tag to an IFD.
void	exif_content_remove_entry (ExifContent *c, ExifEntry *e)
	Remove an EXIF tag from an IFD.
ExifEntry *	exif_content_get_entry (ExifContent *content, ExifTag tag)
	Return the ExifEntry in this IFD corresponding to the given tag.
void	exif_content_fix (ExifContent *c)
	Fix the IFD to bring it into specification.
void	exif_content_foreach_entry (ExifContent *content, ExifContentForeachEntryFunc func, void *user_data)
	Executes function on each EXIF tag in this IFD in turn.
ExifIfd	exif_content_get_ifd (ExifContent *c)
	Return the IFD number in which the given ExifContent is found.
void	exif_content_dump (ExifContent *content, unsigned int indent)
	Dump contents of the IFD to stdout.
void	exif_content_log (ExifContent *content, ExifLog *log)
	Set the log message object for this IFD.

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Detailed Description

Handling EXIF IFDs

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Define Documentation

#define exif_content_get_value	(	c,
		t,
		v,
		m		)

Value:

(exif_content_get_entry (c,t) ?                                 \
         exif_entry_get_value (exif_content_get_entry (c,t),v,m) : NULL)

Return a textual representation of the EXIF data for a tag.

Parameters:

[in]	c	ExifContent* for an IFD
[in]	t	ExifTag to return
[out]	v	char* buffer in which to store value
[in]	m	unsigned int length of the buffer v

Returns:

the v pointer, or NULL on error

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Function Documentation

void exif_content_add_entry	(	ExifContent *	c,
		ExifEntry *	entry
	)

Add an EXIF tag to an IFD.

If this tag already exists in the IFD, this function does nothing.

Precondition:

The "tag" member of the entry must be set on entry.

Parameters:

[out]	c	IFD
[in]	entry	EXIF entry to add

void exif_content_dump	(	ExifContent *	content,
		unsigned int	indent
	)

Dump contents of the IFD to stdout.

This is intended for diagnostic purposes only.

Parameters:

[in]	content	IFD data
[in]	indent	how many levels deep to indent the data

void exif_content_fix

(

ExifContent *

c

)

Fix the IFD to bring it into specification.

Call exif_entry_fix on each entry in this IFD to fix existing entries, create any new entries that are mandatory in this IFD but do not yet exist, and remove any entries that are not allowed in this IFD.

Parameters:

[in,out]

c

EXIF content for an IFD

void exif_content_foreach_entry	(	ExifContent *	content,
		ExifContentForeachEntryFunc	func,
		void *	user_data
	)

Executes function on each EXIF tag in this IFD in turn.

The tags will not necessarily be visited in numerical order.

Parameters:

[in,out]	content	IFD over which to iterate
[in]	func	function to call for each entry
[in]	user_data	data to pass into func on each call

ExifEntry* exif_content_get_entry	(	ExifContent *	content,
		ExifTag	tag
	)

Return the ExifEntry in this IFD corresponding to the given tag.

This is a pointer into a member of the ExifContent array and must NOT be freed or unrefed by the caller.

Parameters:

[in]	content	EXIF content for an IFD
[in]	tag	EXIF tag to return

Returns:

ExifEntry of the tag, or NULL on error

ExifIfd exif_content_get_ifd

(

ExifContent *

c

)

Return the IFD number in which the given ExifContent is found.

Parameters:

[in]

c

an ExifContent*

Returns:

IFD number, or EXIF_IFD_COUNT on error

void exif_content_log	(	ExifContent *	content,
		ExifLog *	log
	)

Set the log message object for this IFD.

Parameters:

[in]	content	IFD
[in]	log	ExifLog*

void exif_content_remove_entry	(	ExifContent *	c,
		ExifEntry *	e
	)

Remove an EXIF tag from an IFD.

If this tag does not exist in the IFD, this function does nothing.

Parameters:

[out]	c	IFD
[in]	e	EXIF entry to remove

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