The MIRC XML Anonymizer

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The XML anonymizer is driven by a script file called "xml-anonymizer.script" located in the same directory where the DicomEditor program is stored. This file is not delivered as part of the installation, so you must construct it yourself using any text editor (e.g., TextPad). Because XML is very general, the script language is different from that of the DICOM anonymizer. It is also different in order to make it look XPath-like for the benefit of XSL wizards.

The following is a quick reference for the scripting language. There are three types of commands. Each starts on the first character of a line. Each is indicated by a specific starting character. A line not starting with one of the three command-start characters is appended to the preceeding line.

  • Any line starting with a '#' character is a comment line.
  • A line starting with an identifier is an assignment command. An identifier always starts with a '$' and is immediately followed by a name, for example, "$UID".
  • A line starting with a '/' character is a path assignment command. Paths are XPath-like expressions, always starting from the root element.

Here are some examples of paths:

  • /MIRCdocument/authorization/owner refers to the "owner" child element of an authorization element in an XML document whose root element is "MIRCdocument".
  • /MIRCdocument/@display refers to the "display" attribute of an XML document whose root element is "MIRCdocument".
  • /*/* refers to any second-generation child element of an XML document, no matter what its root element is named.
  • /*//owner refers to any "owner" element in an XML document, no matter what its root element is named.
  • /message/segment[3] refers to the fourth (always count from zero) "segment" element in an XML document whose root element is "message".

If no bracketed qualifier is present in a path segment, the first element matching the segment name is selected. If all elements matching the segment name are to be selected, use the "[*]" wildcard qualifier, e.g. /root/element[*].

Assignment statements are of two types:

$name = expression 
/path = expression

In a $name assignment, an expression can be any combination of literals (quoted strings, e.g. "some text"), paths, and other names. For a path assignment, an expression can be any combination of literals, paths, names, or function calls. There are three functions:

  • $require( expression ) forces the creation of the element or attribute identified by the path on the left side of the assignment, including all necessary parent elements. The value assigned to the element or attribute is the value of expression argument of the $require function.
  • $remove() causes the element or attribute identified by the path on the left side of the assignment to be removed from the document.
  • $uid( expression ) causes the value of the element to be remapped using the value of the expression as the new UID's root. The UID remapping function uses the same UID remapping table as is used by the DICOM anonymizer, allowing UIDs to be remapped while preserving the relationships between DICOM and XML objects.

Here is an example script for remapping UIDs of two different types in XML files whose root elements are called LidcReadMessage:

$UIDROOT = "1.2.3.4"
/LidcReadMessage/ResponseHeader/SeriesInstanceUid = $uid($UIDROOT)
/LidcReadMessage//imageSOP_UID = $uid($UIDROOT)

Here is an example script for doing the same work as above but at the same time renaming the "SeriesInstanceUid" element to "SeriesInstanceUID":

$UIDROOT = "1.2.3.4"
/LidcReadMessage/ResponseHeader/SeriesInstanceUid = $uid($UIDROOT)
$temp = /LidcReadMessage/ResponseHeader/SeriesInstanceUid
/LidcReadMessage/ResponseHeader/SeriesInstanceUID = $require($temp)
/LidcReadMessage/ResponseHeader/SeriesInstanceUid = $remove()
/LidcReadMessage//imageSOP_UID = $uid($UIDROOT)

To assist in debugging XML anonymizer scripts, there is a special name assignment command:

$print = expression

This causes the value of the expression to be printed on the console. If you are running DicomEditor on a Windows system and want to use this feature, you should launch the program from a command window as described at the top of this page.