Working with DICOM Tables

The internal DICOM tables have been moved from the Leadtools.Dicom.dll to a dedicated Leadtools.Dicom.Tables.dll. This makes the main DICOM DLL (Leadtools.Dicom.dll) significantly smaller in size, and offers developers several new options for accessing and tailoring DICOM tables to the specific requirements of their applications.

There are five DICOM tables that are defined and stored internally in the DICOM toolkit:

Value Representation Table
- Contains a list of all supported value representation defined in the DICOM specification.
- This list is well-defined, does not change, and is small.
- Stored internally in Leadtools.Dicom.dll
Unique Identifier Table (UID)
- Contains a list of all unique identifiers defined in the DICOM specification.
- New UIDs are added ever year.
- Stored internally in Leadtools.Dicom.Tables.dll
- Can be easily and quickly updated by calling LoadXml
Element Tag Table
- Contains a list of all DICOM elements defined in the DICOM specification.
- New elements are added every year.
- Stored internally in both Leadtools.Dicom.Tables.dll and in Leadtools.Dicom.dll
- Can be easily and quickly updated by calling LoadXml.
Information Object Definition Table (IOD)
- Contains a list of all Information Object Definitions defined in the DICOM specification.
- New IODs are defined every year.
- Stored internally in Leadtools.Dicom.Tables.dll
- This is a very large table.
- Can be easily and quickly updated by calling LoadXml.
Context Group Table
- Contains a list of all Context Groups defined in the DICOM specification.
- New Context Groups are added every year.
- Stored internally in Leadtools.Dicom.Tables.dll
- Can be easily and quickly updated by calling LoadXml.

DICOM toolkit users now have several options for using and tailoring the DICOM tables to meet the needs of their applications.

Developers can include Leadtools.Dicom.dll and Leadtools.Dicom.Tables.dll in their distributables. Leadtools.Dicom.Tables.dll includes all UIDs, Element tags, IODs, and DICOM Context Groups from the 2011 DICOM specification. This is the easiest way of using the DICOM tables.
Developers can choose not to include Leadtools.Dicom.Tables.dll in their redistributables. In this case, developers should call the appropriate LoadXml function to load the DICOM tables that they want to load. As part of the toolkit, four human-readable DICOM table XML files are now installed in the LEADTOOLS Sample Images directory:
- dicTableUid.xml - used with LeadDicomUidTable.LoadXml
- dicTableElement.xml - used with LeadDicomTagTable.LoadXml
- dicTableIodModule.xml - used with LeadDicomIodTable.LoadXml
- dicTableContextGroup.xml: used with LeadDicomContextGroupTable.LoadXml

These four tables can easily be tailored. For example, to add new UIDs, elements, IODs, or context groups, developers can edit any one of these files with any text editor. Also, the tables can be easily combined into a single table.

Developers can easily remove those items from tables that will not be used. For example, the DICOM IOD table contains more than 60 IOD definitions and more than 300 module definitions, which comes to more than 18000 lines in the dicTableIodModule.xml file. If a particular DICOM application does not use IODs, then the application footprint can be significantly reduced by not including these IODs at all. Or if you are doing basic DICOM communication, you can include only those IODs that you need, and remove all others. For example, your application might use only the following IODs: