exif-data.h File Reference

#include <libexif/exif-byte-order.h>
#include <libexif/exif-data-type.h>
#include <libexif/exif-ifd.h>
#include <libexif/exif-log.h>
#include <libexif/exif-tag.h>
#include <libexif/exif-content.h>
#include <libexif/exif-mnote-data.h>
#include <libexif/exif-mem.h>

Go to the source code of this file.

Data Structures

struct _ExifData

Represents the entire EXIF data found in an image. More...

Defines

#define exif_data_get_entry(d, t)

Return an ExifEntry for the given tag if found in any IFD.

Typedefs

typedef struct _ExifData ExifData

Represents the entire EXIF data found in an image.

typedef struct
_ExifDataPrivate ExifDataPrivate

typedef void(* ExifDataForeachContentFunc )(ExifContent *, void *user_data)

Enumerations

enum ExifDataOption { EXIF_DATA_OPTION_IGNORE_UNKNOWN_TAGS = 1 << 0, EXIF_DATA_OPTION_FOLLOW_SPECIFICATION = 1 << 1, EXIF_DATA_OPTION_DONT_CHANGE_MAKER_NOTE = 1 << 2 }

Options to configure the behaviour of ExifData. More...

Functions

ExifData * exif_data_new (void)

Allocate a new ExifData.

ExifData * exif_data_new_mem (ExifMem *)

Allocate a new ExifData using the given memory allocator.

ExifData * exif_data_new_from_file (const char *path)

Allocate a new ExifData and load EXIF data from a JPEG file.

ExifData * exif_data_new_from_data (const unsigned char *data, unsigned int size)

Allocate a new ExifData and load EXIF data from a memory buffer.

void exif_data_load_data (ExifData *data, const unsigned char *d, unsigned int size)

Load the ExifData structure from the raw JPEG or EXIF data in the given memory buffer.

void exif_data_save_data (ExifData *data, unsigned char **d, unsigned int *ds)

Store raw EXIF data representing the ExifData structure into a memory buffer.

void exif_data_ref (ExifData *data)

void exif_data_unref (ExifData *data)

void exif_data_free (ExifData *data)

ExifByteOrder exif_data_get_byte_order (ExifData *data)

Return the byte order in use by this EXIF structure.

void exif_data_set_byte_order (ExifData *data, ExifByteOrder order)

Set the byte order to use for this EXIF data.

ExifMnoteData * exif_data_get_mnote_data (ExifData *d)

Return the MakerNote data out of the EXIF data.

void exif_data_fix (ExifData *d)

Fix the EXIF data to bring it into specification.

void exif_data_foreach_content (ExifData *data, ExifDataForeachContentFunc func, void *user_data)

Execute a function on each IFD in turn.

const char * exif_data_option_get_name (ExifDataOption o)

Return a short textual description of the given ExifDataOption.

const char * exif_data_option_get_description (ExifDataOption o)

Return a verbose textual description of the given ExifDataOption.

void exif_data_set_option (ExifData *d, ExifDataOption o)

Set the given option on the given ExifData.

void exif_data_unset_option (ExifData *d, ExifDataOption o)

Clear the given option on the given ExifData.

void exif_data_set_data_type (ExifData *d, ExifDataType dt)

Set the data type for the given ExifData.

ExifDataType exif_data_get_data_type (ExifData *d)

Return the data type for the given ExifData.

void exif_data_dump (ExifData *data)

Dump all EXIF data to stdout.

void exif_data_log (ExifData *data, ExifLog *log)

Set the log message object for all IFDs.

Detailed Description

Defines the ExifData type and the associated functions.

Define Documentation

#define exif_data_get_entry	(	d,
		t		)

Value:

(exif_content_get_entry(d->ifd[EXIF_IFD_0],t) ?                 \
         exif_content_get_entry(d->ifd[EXIF_IFD_0],t) :                 \
         exif_content_get_entry(d->ifd[EXIF_IFD_1],t) ?                 \
         exif_content_get_entry(d->ifd[EXIF_IFD_1],t) :                 \
         exif_content_get_entry(d->ifd[EXIF_IFD_EXIF],t) ?              \
         exif_content_get_entry(d->ifd[EXIF_IFD_EXIF],t) :              \
         exif_content_get_entry(d->ifd[EXIF_IFD_GPS],t) ?               \
         exif_content_get_entry(d->ifd[EXIF_IFD_GPS],t) :               \
         exif_content_get_entry(d->ifd[EXIF_IFD_INTEROPERABILITY],t) ?  \
         exif_content_get_entry(d->ifd[EXIF_IFD_INTEROPERABILITY],t) : NULL)

Return an ExifEntry for the given tag if found in any IFD.

Each IFD is searched in turn and the first containing a tag with this number is returned.

Parameters:

`[in]`	d	ExifData
`[in]`	t	ExifTag

Returns:: ExifEntry* if found, else NULL if not found

Enumeration Type Documentation

enum ExifDataOption

Options to configure the behaviour of ExifData.

Enumerator:

EXIF_DATA_OPTION_IGNORE_UNKNOWN_TAGS	Act as though unknown tags are not present.
EXIF_DATA_OPTION_FOLLOW_SPECIFICATION	Fix the EXIF tags to follow the spec.
EXIF_DATA_OPTION_DONT_CHANGE_MAKER_NOTE	Leave the MakerNote alone, which could cause it to be corrupted.

Function Documentation

void exif_data_dump ( ExifData * data )

Dump all EXIF data to stdout.

This is intended for diagnostic purposes only.

Parameters:

[in] data EXIF data

void exif_data_fix ( ExifData * d )

Fix the EXIF data to bring it into specification.

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

Parameters:

[in,out] d EXIF data

void exif_data_foreach_content	(	ExifData *	data,
		ExifDataForeachContentFunc	func,
		void *	user_data
	)

Execute a function on each IFD in turn.

Parameters:

`[in]`	data	EXIF data over which to iterate
`[in]`	func	function to call for each entry
`[in]`	user_data	data to pass into func on each call

ExifByteOrder exif_data_get_byte_order ( ExifData * data )

Return the byte order in use by this EXIF structure.

Parameters:

[in] data EXIF data

Returns:: byte order

ExifDataType exif_data_get_data_type ( ExifData * d )

Return the data type for the given ExifData.

Parameters:

[in] d EXIF data

Returns:: data type, or EXIF_DATA_TYPE_UNKNOWN on error

ExifMnoteData* exif_data_get_mnote_data ( ExifData * d )

Return the MakerNote data out of the EXIF data.

Only certain MakerNote formats that are recognized by libexif are supported. The pointer references a member of the ExifData structure and must NOT be freed by the caller.

Parameters:

[in] d EXIF data

Returns:: MakerNote data, or NULL if not found or not supported

void exif_data_load_data	(	ExifData *	data,
		const unsigned char *	d,
		unsigned int	size
	)

Load the ExifData structure from the raw JPEG or EXIF data in the given memory buffer.

If the EXIF data contains a recognized MakerNote, it is loaded and stored as well for later retrieval by exif_data_get_mnote_data. If the EXIF_DATA_OPTION_FOLLOW_SPECIFICATION option has been set on this ExifData, then the tags are automatically fixed after loading (by calling exif_data_fix).

Parameters:

`[in,out]`	data	EXIF data
`[in]`	d	pointer to raw JPEG or EXIF data
`[in]`	size	number of bytes of data at d

void exif_data_log	(	ExifData *	data,
		ExifLog *	log
	)

Set the log message object for all IFDs.

Parameters:

`[in]`	data	EXIF data
`[in]`	log	ExifLog

ExifData* exif_data_new ( void )

Allocate a new ExifData.

The ExifData contains an empty ExifContent for each IFD and the default set of options, which has EXIF_DATA_OPTION_IGNORE_UNKNOWN_TAGS and EXIF_DATA_OPTION_FOLLOW_SPECIFICATION set.

Returns:: allocated ExifData, or NULL on error

ExifData* exif_data_new_from_data	(	const unsigned char *	data,
		unsigned int	size
	)

Allocate a new ExifData and load EXIF data from a memory buffer.

Parameters:

`[in]`	data	pointer to raw JPEG or EXIF data
`[in]`	size	number of bytes of data at data

Returns:: allocated ExifData, or NULL on error

ExifData* exif_data_new_from_file ( const char * path )

Allocate a new ExifData and load EXIF data from a JPEG file.

Uses an ExifLoader internally to do the loading.

Parameters:

[in] path filename including path

Returns:: allocated ExifData, or NULL on error

ExifData* exif_data_new_mem ( ExifMem * )

Allocate a new ExifData using the given memory allocator.

The ExifData contains an empty ExifContent for each IFD and the default set of options, which has EXIF_DATA_OPTION_IGNORE_UNKNOWN_TAGS and EXIF_DATA_OPTION_FOLLOW_SPECIFICATION set.

Returns:: allocated ExifData, or NULL on error

const char* exif_data_option_get_description ( ExifDataOption o )

Return a verbose textual description of the given ExifDataOption.

Parameters:

[in] o option

Returns:: verbose localized textual description of the option

const char* exif_data_option_get_name ( ExifDataOption o )

Return a short textual description of the given ExifDataOption.

Parameters:

[in] o option

Returns:: localized textual description of the option

void exif_data_save_data	(	ExifData *	data,
		unsigned char **	d,
		unsigned int *	ds
	)

Store raw EXIF data representing the ExifData structure into a memory buffer.

The buffer is allocated by this function and must subsequently be freed by the caller using the matching free function as used by the ExifMem in use by this ExifData.

Parameters:

`[in]`	data	EXIF data
`[out]`	d	pointer to buffer pointer containing raw EXIF data on return
`[out]`	ds	pointer to variable to hold the number of bytes of data at d, or set to 0 on error

void exif_data_set_byte_order	(	ExifData *	data,
		ExifByteOrder	order
	)

Set the byte order to use for this EXIF data.

If any tags already exist (including MakerNote tags) they are are converted to the specified byte order.

Parameters:

`[in,out]`	data	EXIF data
`[in]`	order	byte order

void exif_data_set_data_type	(	ExifData *	d,
		ExifDataType	dt
	)

Set the data type for the given ExifData.

Parameters:

`[in]`	d	EXIF data
`[in]`	dt	data type

void exif_data_set_option	(	ExifData *	d,
		ExifDataOption	o
	)

Set the given option on the given ExifData.

Parameters:

`[in]`	d	EXIF data
`[in]`	o	option

void exif_data_unset_option	(	ExifData *	d,
		ExifDataOption	o
	)

Clear the given option on the given ExifData.

Parameters:

`[in]`	d	EXIF data
`[in]`	o	option

Generated by


Data Structures
struct	_ExifData
	Represents the entire EXIF data found in an image. More...
Defines
#define	exif_data_get_entry(d, t)
	Return an ExifEntry for the given tag if found in any IFD.
Typedefs
typedef struct _ExifData	ExifData
	Represents the entire EXIF data found in an image.
typedef struct _ExifDataPrivate	ExifDataPrivate
typedef void(*	ExifDataForeachContentFunc )(ExifContent , void user_data)
Enumerations
enum	ExifDataOption { EXIF_DATA_OPTION_IGNORE_UNKNOWN_TAGS = 1 << 0, EXIF_DATA_OPTION_FOLLOW_SPECIFICATION = 1 << 1, EXIF_DATA_OPTION_DONT_CHANGE_MAKER_NOTE = 1 << 2 }
	Options to configure the behaviour of ExifData. More...
Functions
ExifData *	exif_data_new (void)
	Allocate a new ExifData.
ExifData *	exif_data_new_mem (ExifMem *)
	Allocate a new ExifData using the given memory allocator.
ExifData *	exif_data_new_from_file (const char *path)
	Allocate a new ExifData and load EXIF data from a JPEG file.
ExifData *	exif_data_new_from_data (const unsigned char *data, unsigned int size)
	Allocate a new ExifData and load EXIF data from a memory buffer.
void	exif_data_load_data (ExifData data, const unsigned char d, unsigned int size)
	Load the ExifData structure from the raw JPEG or EXIF data in the given memory buffer.
void	exif_data_save_data (ExifData data, unsigned char d, unsigned int ds)
	Store raw EXIF data representing the ExifData structure into a memory buffer.
void	exif_data_ref (ExifData *data)
void	exif_data_unref (ExifData *data)
void	exif_data_free (ExifData *data)
ExifByteOrder	exif_data_get_byte_order (ExifData *data)
	Return the byte order in use by this EXIF structure.
void	exif_data_set_byte_order (ExifData *data, ExifByteOrder order)
	Set the byte order to use for this EXIF data.
ExifMnoteData *	exif_data_get_mnote_data (ExifData *d)
	Return the MakerNote data out of the EXIF data.
void	exif_data_fix (ExifData *d)
	Fix the EXIF data to bring it into specification.
void	exif_data_foreach_content (ExifData data, ExifDataForeachContentFunc func, void user_data)
	Execute a function on each IFD in turn.
const char *	exif_data_option_get_name (ExifDataOption o)
	Return a short textual description of the given ExifDataOption.
const char *	exif_data_option_get_description (ExifDataOption o)
	Return a verbose textual description of the given ExifDataOption.
void	exif_data_set_option (ExifData *d, ExifDataOption o)
	Set the given option on the given ExifData.
void	exif_data_unset_option (ExifData *d, ExifDataOption o)
	Clear the given option on the given ExifData.
void	exif_data_set_data_type (ExifData *d, ExifDataType dt)
	Set the data type for the given ExifData.
ExifDataType	exif_data_get_data_type (ExifData *d)
	Return the data type for the given ExifData.
void	exif_data_dump (ExifData *data)
	Dump all EXIF data to stdout.
void	exif_data_log (ExifData data, ExifLog log)
	Set the log message object for all IFDs.