Program: gdcm
Module: $RCSfile: gdcmCommon.h,v $
Language: C++
- Date: $Date: 2004/09/09 17:49:24 $
- Version: $Revision: 1.30 $
+ Date: $Date: 2004/09/21 11:17:42 $
+ Version: $Revision: 1.32 $
Copyright (c) CREATIS (Centre de Recherche et d'Applications en Traitement de
l'Image). All rights reserved. See Doc/License.txt or
const std::string GDCM_NOTLOADED = "gdcm::NotLoaded";
const std::string GDCM_UNREAD = "gdcm::UnRead";
+/// \brief gdcmTagKey is made to old an "universal" (as in URL, Universal
+/// Ressource Locator) key to a gdcmDocEntry i.e. a dicom tag.
+/// A dicom tag allways has a group and an element, but a set of tags
+/// embeded in various (optionally nested) sequences and sharing
+/// the same group and element all share the same (group, element)
+/// "identifier". Hence the (group, element) cannot be used as an
+/// identifier (in gdcm we shall refer to a "TagKey") of a tag.
+/// In order to construct a proper tag identifier (i.e. a key) we
+/// consider the following definition of a TagKey:
+/// - let Group, Element be the string representation of the
+/// group and element dicom tag members,
+/// - let ItemNumber be the string representation of the integer
+/// index of the considered item number of a sequence,
+/// Let the key of a tag embeded in a sequence, noted SeqTag, be
+/// the form:
+/// /ItemNumber#Group|Element
+/// where "/", "#" and "|" are characters acting as separators.
+/// Then the general form of a gdcmTagKey is given by:
+/// Group|Element[SeqTag]
+/// where [SeqTag] means NO or many instances of SeqTag.
+/// Hence the gdcmTagKey of a tag not "leaving" in a sequence is the
+/// string e.g.
+/// 0028|1201
+/// but the gdcmTagKey of a tag "embeded" is the first item of
+/// a sequence, itself nested in the third item of a sequence is the
+/// string e.g.
+/// 0004|1220/2#0008|0082/0#0008|0090
typedef std::string gdcmTagKey;
typedef std::string TagName;