Working with Information Object Definitions

An Information Object Definition (IOD) is an abstract data model that specifies information about Real-World objects. It provides a means of standardizing information exchanged between applications. There are a tremendous number of IODs that are standard for the DICOM file format. In addition to the standard IODs, user-defined IODs may also be added.

LEADTOOLS maintains a tree internally of all available Information Object Definitions (IODs), standard and user defined. In this documentation the tree of available IODs will be referred to as the IOD Structure, since some functions allow you to evaluate the internal IOD Structure as a tree or as a list. Unfortunately, the collection of default IODs is too large to include a table of default values in this documentation. For more information on IOD defaults, refer to the DICOM Standard.

LEADTOOLS provides a number of functions for maneuvering through and modifying the IOD Structure. All functions pertaining to the IOD Structure are in the class LDicomIOD.

For maneuvering through the IOD Structure, LEADTOOLS provides the following functions:

LDicomIOD::GetRoot

LDicomIOD::GetParent

LDicomIOD::GetChild

LDicomIOD::GetFirst

LDicomIOD::GetLast

LDicomIOD::GetPrev

LDicomIOD::GetNext

LDicomIOD::GetCountModule

LEADTOOLS provides several functions for searching the IOD Structure. To find the IOD for a specific class or module, use LDicomIOD::FindClass and LDicomIOD::FindModule. You can find the IOD for elements, modules or classes using LDicomIOD::Find. If you want to find the IOD for the module at a specific position in a specific class, use LDicomIOD::FindIndexModule.

To insert new items in the IOD Structure, call LDicomIOD::Insert.

You can delete individual items from the IOD Structure using LDicomIOD::Delete, or you can delete all items from the IOD Structure, using LDicomIOD::Reset.

To change the name or the description of an IOD already in the IOD Structure, call LDicomIOD::SetName and LDicomIOD::SetDescription.

To determine whether you have a valid pointer to an IOD item, call LDicomIOD::Exists.

To load DICOM IODs from a file, call LDicomIOD::LoadXml.

Finally, to reset the IOD Structure to the default values, use LDicomIOD::Default.

For more information on IODs, refer to An Overview of the DICOM File Format or the DICOM Standard.