<!-- ##### SECTION Title ##### -->
Tag Specifications

<!-- ##### SECTION Short_Description ##### -->
querying tag usage information from the IPTC IIM specification

<!-- ##### SECTION Long_Description ##### -->
<para>
These functions allow queries to the <ulink url="http://www.iptc.org/IIM">IPTC IIM
specification</ulink> which contains information about the purpose of each IPTC
tag, along with any requirements such as maximum/minimum data length, data type,
repeatability and whether the tag is mandatory.
</para>

<!-- ##### SECTION See_Also ##### -->
<para>

</para>

<!-- ##### SECTION Stability_Level ##### -->


<!-- ##### ENUM IptcRecord ##### -->
<para>
The record number that, together with the tag number (#IptcTag),
uniquely identifies the purpose of a tag.
</para>

@IPTC_RECORD_OBJECT_ENV: the record used for file information such
as file format, version, unique identifier, etc.  This is often
not used for photo-management applications.
@IPTC_RECORD_APP_2: the record used for application-specific tags
such as Caption, Keywords, etc.
@IPTC_RECORD_APP_3: application-specific tags
@IPTC_RECORD_APP_4: application-specific tags
@IPTC_RECORD_APP_5: application-specific tags
@IPTC_RECORD_APP_6: application-specific tags
@IPTC_RECORD_PREOBJ_DATA: contains information about an encapsulated file
@IPTC_RECORD_OBJ_DATA: the encapsulated file data (usually not used)
@IPTC_RECORD_POSTOBJ_DATA: followup information about an encapsulated file

<!-- ##### ENUM IptcTag ##### -->
<para>
The tag number that, together with the record number (#IptcRecord),
uniquely identifies the purpose of a tag.
</para>

@IPTC_TAG_MODEL_VERSION: 
@IPTC_TAG_DESTINATION: 
@IPTC_TAG_FILE_FORMAT: 
@IPTC_TAG_FILE_VERSION: 
@IPTC_TAG_SERVICE_ID: 
@IPTC_TAG_ENVELOPE_NUM: 
@IPTC_TAG_PRODUCT_ID: 
@IPTC_TAG_ENVELOPE_PRIORITY: 
@IPTC_TAG_DATE_SENT: 
@IPTC_TAG_TIME_SENT: 
@IPTC_TAG_CHARACTER_SET: 
@IPTC_TAG_UNO: 
@IPTC_TAG_ARM_ID: 
@IPTC_TAG_ARM_VERSION: 
@IPTC_TAG_RECORD_VERSION: 
@IPTC_TAG_OBJECT_TYPE: 
@IPTC_TAG_OBJECT_ATTRIBUTE: 
@IPTC_TAG_OBJECT_NAME: 
@IPTC_TAG_EDIT_STATUS: 
@IPTC_TAG_EDITORIAL_UPDATE: 
@IPTC_TAG_URGENCY: 
@IPTC_TAG_SUBJECT_REFERENCE: 
@IPTC_TAG_CATEGORY: 
@IPTC_TAG_SUPPL_CATEGORY: 
@IPTC_TAG_FIXTURE_ID: 
@IPTC_TAG_KEYWORDS: 
@IPTC_TAG_CONTENT_LOC_CODE: 
@IPTC_TAG_CONTENT_LOC_NAME: 
@IPTC_TAG_RELEASE_DATE: 
@IPTC_TAG_RELEASE_TIME: 
@IPTC_TAG_EXPIRATION_DATE: 
@IPTC_TAG_EXPIRATION_TIME: 
@IPTC_TAG_SPECIAL_INSTRUCTIONS: 
@IPTC_TAG_ACTION_ADVISED: 
@IPTC_TAG_REFERENCE_SERVICE: 
@IPTC_TAG_REFERENCE_DATE: 
@IPTC_TAG_REFERENCE_NUMBER: 
@IPTC_TAG_DATE_CREATED: 
@IPTC_TAG_TIME_CREATED: 
@IPTC_TAG_DIGITAL_CREATION_DATE: 
@IPTC_TAG_DIGITAL_CREATION_TIME: 
@IPTC_TAG_ORIGINATING_PROGRAM: 
@IPTC_TAG_PROGRAM_VERSION: 
@IPTC_TAG_OBJECT_CYCLE: 
@IPTC_TAG_BYLINE: 
@IPTC_TAG_BYLINE_TITLE: 
@IPTC_TAG_CITY: 
@IPTC_TAG_SUBLOCATION: 
@IPTC_TAG_STATE: 
@IPTC_TAG_COUNTRY_CODE: 
@IPTC_TAG_COUNTRY_NAME: 
@IPTC_TAG_ORIG_TRANS_REF: 
@IPTC_TAG_HEADLINE: 
@IPTC_TAG_CREDIT: 
@IPTC_TAG_SOURCE: 
@IPTC_TAG_COPYRIGHT_NOTICE: 
@IPTC_TAG_PICASA_UNKNOWN: 
@IPTC_TAG_CONTACT: 
@IPTC_TAG_CAPTION: 
@IPTC_TAG_WRITER_EDITOR: 
@IPTC_TAG_RASTERIZED_CAPTION: 
@IPTC_TAG_IMAGE_TYPE: 
@IPTC_TAG_IMAGE_ORIENTATION: 
@IPTC_TAG_LANGUAGE_ID: 
@IPTC_TAG_AUDIO_TYPE: 
@IPTC_TAG_AUDIO_SAMPLING_RATE: 
@IPTC_TAG_AUDIO_SAMPLING_RES: 
@IPTC_TAG_AUDIO_DURATION: 
@IPTC_TAG_AUDIO_OUTCUE: 
@IPTC_TAG_PREVIEW_FORMAT: 
@IPTC_TAG_PREVIEW_FORMAT_VER: 
@IPTC_TAG_PREVIEW_DATA: 
@IPTC_TAG_SIZE_MODE: 
@IPTC_TAG_MAX_SUBFILE_SIZE: 
@IPTC_TAG_SIZE_ANNOUNCED: 
@IPTC_TAG_MAX_OBJECT_SIZE: 
@IPTC_TAG_SUBFILE: 
@IPTC_TAG_CONFIRMED_DATA_SIZE: 

<!-- ##### STRUCT IptcTagInfo ##### -->
<para>
Contains static information about a specific tag (identified by its
record-tag pair) from the IPTC IIM specificiation.  This info is for
reference only and should never be modified by an application.
</para>

@record: record number of the tag
@tag: dataset number of the tag
@name: English name of the tag (no spaces)
@title: English title of the tag (may contain spaces)
@description: English description of the tag
@format: data format of the tag
@mandatory: whether the specification says the tag
is required
@repeatable: whether the specification says the tag
can appear more than once
@minbytes: minimum number of bytes in the tag value
@maxbytes: maximum number of bytes in the tag value

<!-- ##### ENUM IptcFormat ##### -->
<para>
The possible data formats for a tag's value, derived from the IPTC IIM
specification.  Integer formats are always represented with the most
significant byte first (big-endian) in the IPTC bytestream.
</para>

@IPTC_FORMAT_UNKNOWN: Unknown format (for a tag not in the specification)
@IPTC_FORMAT_BINARY: Binary data (variable length)
@IPTC_FORMAT_BYTE: 1-byte integer
@IPTC_FORMAT_SHORT: 2-byte integer (big-endian)
@IPTC_FORMAT_LONG: 4-byte integer (big-endian)
@IPTC_FORMAT_STRING: String data (variable length, of any character set)
@IPTC_FORMAT_NUMERIC_STRING: String containing only numerals (variable length)
@IPTC_FORMAT_DATE: String of the format "YYYYMMDD" (8 bytes)
@IPTC_FORMAT_TIME: String of the format "HHMMSS&plusmn;HHMM" where the second
HHMM defines the timezone offset (11 bytes)

<!-- ##### ENUM IptcMandatory ##### -->
<para>
Whether a tag is mandatory according to the IPTC IIM specification.
Note that most applications ignore this aspect of the specification
since the spec was designed to encapsulate the media file rather than
the other way around (which is how nearly all applications use it).
This renders most mandatory tags unnecessary.
</para>

@IPTC_OPTIONAL: tag is allowed to be absent
@IPTC_MANDATORY: tag must be present

<!-- ##### ENUM IptcRepeatable ##### -->
<para>
Whether a tag can occur more than once according to the IPTC IIM
specification.  For example, the "Keywords" tag only contains a single
keyword, but the tag itself is repeated for media that references more
than one keyword.
</para>

@IPTC_NOT_REPEATABLE: tag can only appear once
@IPTC_REPEATABLE: tag can be repeated

<!-- ##### FUNCTION iptc_tag_get_name ##### -->
<para>

</para>

@record: 
@tag: 
@Returns: 


<!-- ##### FUNCTION iptc_tag_get_title ##### -->
<para>

</para>

@record: 
@tag: 
@Returns: 


<!-- ##### FUNCTION iptc_tag_get_description ##### -->
<para>

</para>

@record: 
@tag: 
@Returns: 


<!-- ##### FUNCTION iptc_tag_get_info ##### -->
<para>

</para>

@record: 
@tag: 
@Returns: 


<!-- ##### FUNCTION iptc_format_get_name ##### -->
<para>

</para>

@format: 
@Returns: 


<!-- ##### FUNCTION iptc_tag_find_by_name ##### -->
<para>

</para>

@name: 
@record: 
@tag: 
@Returns: