IptcData

typedef struct {
        IptcDataSet **datasets;
        unsigned int count;

	IptcDataPrivate *priv;
} IptcData;

Represents the collection of datasets that make up a IPTC data block.

iptc_data_new ()

IptcData*           iptc_data_new                       (void);

Allocates a new collection of datasets, which is initialized to be empty. The default memory allocation functions (malloc, etc.) are used. If you need custom memory management functions, use iptc_data_new_mem() instead. This allocation will set the IptcData refcount to 1, so use iptc_data_unref() when finished with the pointer.

iptc_data_new_mem ()

IptcData*           iptc_data_new_mem                   (IptcMem *mem);

Allocates a new collection of datasets, which is initialized to be empty, using custom memory management functions. This allocation will set the IptcData refcount to 1, so use iptc_data_unref() when finished with the object.

iptc_data_ref ()

void                iptc_data_ref                       (IptcData *data);

Increments the reference count of an IptcData object. This function should be called whenever a copy of a pointer is made by the application. iptc_data_unref() can then be used when the pointer is no longer needed to ensure that the object is freed once the object is completely unused.

iptc_data_unref ()

void                iptc_data_unref                     (IptcData *data);

Decrements the reference count of an IptcData object. The object will automatically be freed when the count reaches 0. This function should be called whenever a pointer is no longer needed by an application. It is also good practice to set the local copy of the pointer to NULL to shield against accidently reusing the value.

iptc_data_free ()

void                iptc_data_free                      (IptcData *data);

Frees an IptcData object. This function should be used only for error handling since iptc_data_unref() provides a safer mechanism for freeing that allows multiple components to have access to an object. This function decrements the reference count of any datasets contained by the object. This will generally cause them to be freed as well unless other parts of the application are referencing them individually.

iptc_data_new_from_jpeg ()

IptcData*           iptc_data_new_from_jpeg             (const char *path);

Allocates a new collection of datasets which is initialized by decoding the IPTC data in JPEG file path. This allocation will set the IptcData refcount to 1, so use iptc_data_unref() when finished with the object. This is a convenience function that reads the contents of the file, creates a new IptcData object, parses the file with iptc_jpeg_read_ps3() and iptc_jpeg_ps3_find_iptc(), and loads the data with iptc_data_load(). If more fine-grained error detection is needed, those functions should be used individually.

iptc_data_new_from_data ()

IptcData*           iptc_data_new_from_data             (unsigned char *buf,
                                                         unsigned int size);

Allocates a new collection of datasets which is initialized by decoding the contents of buf. This allocation will set the IptcData refcount to 1, so use iptc_data_unref() when finished with the object. This is simply a convenience function that can be duplicated by calling iptc_data_new() followed by iptc_data_load().

iptc_data_load ()

int                 iptc_data_load                      (IptcData *data,
                                                         unsigned char *buf,
                                                         unsigned int size);

Parses a buffer containing raw IPTC data and adds the datasets to the IptcData object data.

iptc_data_save ()

int                 iptc_data_save                      (IptcData *data,
                                                         unsigned char **buf,
                                                         unsigned int *size);

Outputs a collection of datasets as an IPTC bytestream. No memory allocation is required in advance. buf should point to a NULL pointer that will be set to the address of the output buffer by this function. size will contain this buffer's length after completion. The object data is unmodified by this function. The application should free the output buffer using iptc_data_free_buf() when it is no longer needed.

iptc_data_free_buf ()

void                iptc_data_free_buf                  (IptcData *data,
                                                         unsigned char *buf);

Frees a temporary buffer created from an IptcData object by the iptc_data_save() function.

iptc_data_get_dataset ()

IptcDataSet*        iptc_data_get_dataset               (IptcData *data,
                                                         IptcRecord record,
                                                         IptcTag tag);

Finds the first occurence of a dataset inside a collection with the specified record and tag identifiers.

iptc_data_get_next_dataset ()

IptcDataSet*        iptc_data_get_next_dataset          (IptcData *data,
                                                         IptcDataSet *ds,
                                                         IptcRecord record,
                                                         IptcTag tag);

Finds the next occurence of a dataset inside a collection with the specified record and tag identifiers following ds. This is useful when a collection contains more than one dataset with the same record and tag identifier (for example, the keywords tag appears once for each keyword in the IPTC metadata). When ds is NULL, this function is equivalent to iptc_data_get_dataset().

iptc_data_add_dataset ()

int                 iptc_data_add_dataset               (IptcData *data,
                                                         IptcDataSet *ds);

Adds an IptcDataSet at the end of an existing collection. A dataset can only be a member of a single collection. This function will increment the reference count of dataset, so if the application no longer intends to use dataset directly, it should call iptc_dataset_unref() immediately following this call.

iptc_data_add_dataset_before ()

int                 iptc_data_add_dataset_before        (IptcData *data,
                                                         IptcDataSet *ds,
                                                         IptcDataSet *newds);

Same as iptc_data_add_dataset(), except the dataset will be added before an existing dataset ds, so that if they are enumerated, newds will appear before ds in the collection. ds must be a dataset already present in the collection.

iptc_data_add_dataset_after ()

int                 iptc_data_add_dataset_after         (IptcData *data,
                                                         IptcDataSet *ds,
                                                         IptcDataSet *newds);

Same as iptc_data_add_dataset(), except the dataset will be added after an existing dataset ds, so that if they are enumerated, newds will appear after ds in the collection. ds must be a dataset already present in the collection.

iptc_data_remove_dataset ()

int                 iptc_data_remove_dataset            (IptcData *data,
                                                         IptcDataSet *ds);

Removes a dataset from a collection. This function also calls iptc_dataset_unref() on ds.

IptcDataForeachDataSetFunc ()

void                (*IptcDataForeachDataSetFunc)       (IptcDataSet *dataset,
                                                         void *user_data);

Application callback executed for each dataset from iptc_data_foreach_dataset().

iptc_data_foreach_dataset ()

void                iptc_data_foreach_dataset           (IptcData *data,
                                                         IptcDataForeachDataSetFunc func,
                                                         void *user_data);

Iterates through each dataset in the collection and calls the callback function on that dataset.

iptc_data_sort ()

void                iptc_data_sort                      (IptcData *data);

Sorts a collection of datasets in ascending order first by record number and second by tag number. It can be useful to call this function before saving IPTC data in order to maintain a more organized file.

enum IptcEncoding

typedef enum {
	IPTC_ENCODING_UNKNOWN = 0,
	IPTC_ENCODING_UNSPECIFIED = 1,
	IPTC_ENCODING_UTF8 = 2
} IptcEncoding;

iptc_data_get_encoding ()

IptcEncoding        iptc_data_get_encoding              (IptcData *data);

Identifies the character encoding of the collection of datasets as specified by the "character set" dataset (1:90). The specification allows this dataset to contain control sequences from the ISO 2022 standard. Unfortunately, this standard is very complicated and generally not used by application writers. Thus, rather than attempt to decode any possible any possible control sequence, this function only attempts to recognize the control sequence that identifies the UTF-8 character set. If found, this function will return IPTC_ENCODING_UTF8. All character-based datasets in record 2 and higher are then expected to contain data encoded in the UTF-8 character set. Otherwise, this function will return IPTC_ENCODING_UNKNOWN, meaning that any other character set might be used, including ISO 2022 control sequences that have not been decoded. If dataset 1:90 is not present, this function returns IPTC_ENCODING_UNSPECIFIED, in which case character-based datasets will usually be plain ASCII, although broken applications may have used some other encoding.

iptc_data_set_encoding_utf8 ()

int                 iptc_data_set_encoding_utf8         (IptcData *data);

Sets the contents of the "character set" dataset (1:90) to contain the control sequence that indicates UTF-8 as the character encoding for any character-based datasets in record 2 or higher. If dataset 1:90 is not present, it will be added to the collection. Any prior value of dataset 1:90 will be overwritten by this function. Note that some third-party applications (notably Picasa) will ignore all your IPTC data if this option is set.

IPTC_IIM_VERSION

#define IPTC_IIM_VERSION	4

The version of the IPTC IIM specification implemented by this library.

iptc_data_set_version ()

int                 iptc_data_set_version               (IptcData *data,
                                                         unsigned int version);

Specifies the version of the IIM specification used by this library by setting the value of datasets 1:00 and 2:00. It is recommended to set the version number to IPTC_IIM_VERSION, which specifies the version implemented by this library (currently 4). If datasets 1:00 or 2:00 are not present, they will be added to the collection. Any prior value of the datasets will be overwritten by this function. To ensure strict compliance with the standard, this function should be called before saving a collection of datasets. However, in practice, some applications (notably Picasa) will ignore all your IPTC data if this option is set.

iptc_data_add_dataset_with_value ()

int                 iptc_data_add_dataset_with_value    (IptcData *data,
                                                         IptcRecord record,
                                                         IptcTag tag,
                                                         unsigned int value,
                                                         IptcValidate validate);

This is a convenience function that creates a new dataset with the given record and tag, adds it to the specified collection of datasets, and stores the given numeric value as the contents of the dataset. It is equivalent to calling this sequence of functions: iptc_dataset_new(), iptc_dataset_set_tag(), iptc_data_add_dataset(), and iptc_dataset_set_value().

iptc_data_add_dataset_with_contents ()

int                 iptc_data_add_dataset_with_contents (IptcData *data,
                                                         IptcRecord record,
                                                         IptcTag tag,
                                                         unsigned char *buf,
                                                         unsigned int size,
                                                         IptcValidate validate);

This is a convenience function that creates a new dataset with the given record and tag, adds it to the specified collection of datasets, and stores a copy of the given data buffer as the contents of the dataset. It is equivalent to calling this sequence of functions: iptc_dataset_new(), iptc_dataset_set_tag(), iptc_data_add_dataset(), and iptc_dataset_set_data().

iptc_data_dump ()

void                iptc_data_dump                      (IptcData *data,
                                                         unsigned int indent);

A debugging aid that prints out the contents of a collection of datasets to standard output.

iptc_data_log ()

void                iptc_data_log                       (IptcData *data,
                                                         IptcLog *log);

Changes the logging object for a IptcData object. The logging object determines how warning and error messages are relayed back to the application. This function also calls iptc_log_ref() on the new log object and iptc_log_unref() on the previous log object.