Trait DataDictionary

Source

pub trait DataDictionary {
    type Entry: DataDictionaryEntry;

    // Required methods
    fn by_tag(&self, tag: Tag) -> Option<&Self::Entry>;
    fn by_name(&self, name: &str) -> Option<&Self::Entry>;

    // Provided methods
    fn by_expr(&self, tag: &str) -> Option<&Self::Entry> { ... }
    fn parse_tag(&self, tag: &str) -> Option<Tag> { ... }
    fn parse_selector(
        &self,
        selector_text: &str,
    ) -> Result<AttributeSelector, ParseSelectorError> { ... }
}

Expand description

Type trait for a dictionary of DICOM attributes.

The main purpose of an attribute dictionary is to retrieve a record containing additional information about a data element, in one of the following ways:

By DICOM tag, via by_tag;
By its keyword (also known as alias) via by_name;
By an expression which may either be a keyword or a tag printed in one of its standard forms, using by_expr.

These methods will return None when the tag or name is not recognized by the dictionary.

In addition, the data element dictionary provides built-in DICOM tag and selector (path) parsers for convenience. parse_tag converts an arbitrary expression to a tag, whereas parse_selector produces an attribute selector.

Required Associated Types§

Source

type Entry: DataDictionaryEntry

The type of the dictionary entry.

Required Methods§

Source

fn by_tag(&self, tag: Tag) -> Option<&Self::Entry>

Fetch a data element entry by its tag.

Source

fn by_name(&self, name: &str) -> Option<&Self::Entry>

Fetch an entry by its usual alias (e.g. “PatientName” or “SOPInstanceUID”). Aliases (or keyword) are usually in UpperCamelCase, not separated by spaces, and are case sensitive.

Querying the dictionary by name is usually slightly more expensive than by DICOM tag. If the parameter provided is a string literal (e.g. "StudyInstanceUID"), then it may be better to use by_tag with a known tag constant (such as tags::STUDY_INSTANCE_UID from the dicom-dictionary-std crate).

Provided Methods§

Source

fn by_expr(&self, tag: &str) -> Option<&Self::Entry>

Fetch an entry by its alias or by DICOM tag expression.

This method accepts a tag descriptor in any of the following formats:

(gggg,eeee): a 4-digit hexadecimal group part and a 4-digit hexadecimal element part surrounded by parentheses
gggg,eeee: a 4-digit hexadecimal group part and a 4-digit hexadecimal element part not surrounded by parentheses
KeywordName: an exact match (case sensitive) by DICOM tag keyword

When failing to identify the intended syntax or the tag keyword, None is returned.

Source

fn parse_tag(&self, tag: &str) -> Option<Tag>

Use this data element dictionary to interpret a DICOM tag.

This method accepts a tag descriptor in any of the following formats:

(gggg,eeee): a 4-digit hexadecimal group part and a 4-digit hexadecimal element part surrounded by parentheses
gggg,eeee: a 4-digit hexadecimal group part and a 4-digit hexadecimal element part not surrounded by parentheses
KeywordName: an exact match (case sensitive) by DICOM tag keyword

When failing to identify the intended syntax or the tag keyword, None is returned.

Source

fn parse_selector( &self, selector_text: &str, ) -> Result<AttributeSelector, ParseSelectorError>

Parse a string as an attribute selector.

Attribute selectors are defined by the syntax ( «key»([«item»])? . )* «key» where_«key»_ is either a DICOM tag or keyword as accepted by this dictionary when calling the method parse_tag. More details about the syntax can be found in the documentation of AttributeSelector.

Returns an error if the string does not follow the given syntax, or one of the key components could not be resolved.

§Examples of valid input:

(0002,00010): Transfer Syntax UID
00101010: Patient Age
0040A168[0].CodeValue: Code Value in first item of Concept Code Sequence
SequenceOfUltrasoundRegions.RegionSpatialFormat: Region Spatial Format in first item of Sequence of Ultrasound Regions