Class BeiderMorseEncoder
Encodes strings into their Beider-Morse phonetic encoding.
Inheritance
Assembly: Lucene.Net.Analysis.Phonetic.dll
Syntax
public class BeiderMorseEncoder : object, IStringEncoder
Remarks
Beider-Morse phonetic encodings are optimised for family names. However, they may be useful for a wide range of words.
This encoder is intentionally mutable to allow dynamic configuration through bean properties. As such, it is mutable, and may not be thread-safe. If you require a guaranteed thread-safe encoding then use PhoneticEngine directly.
Encoding overview
Beider-Morse phonetic encodings is a multi-step process. Firstly, a table of rules is consulted to guess what
language the word comes from. For example, if it ends in "ault
" then it infers that the word is French.
Next, the word is translated into a phonetic representation using a language-specific phonetics table. Some
runs of letters can be pronounced in multiple ways, and a single run of letters may be potentially broken up
into phonemes at different places, so this stage results in a set of possible language-specific phonetic
representations. Lastly, this language-specific phonetic representation is processed by a table of rules that
re-writes it phonetically taking into account systematic pronunciation differences between languages, to move
it towards a pan-indo-european phonetic representation. Again, sometimes there are multiple ways this could be
done and sometimes things that can be pronounced in several ways in the source language have only one way to
represent them in this average phonetic language, so the result is again a set of phonetic spellings.
Some names are treated as having multiple parts. This can be due to two things. Firstly, they may be hyphenated.
In this case, each individual hyphenated word is encoded, and then these are combined end-to-end for the final
encoding. Secondly, some names have standard prefixes, for example, "Mac/Mc
" in Scottish (English)
names. As sometimes it is ambiguous whether the prefix is intended or is an accident of the spelling, the word
is encoded once with the prefix and once without it. The resulting encoding contains one and then the other result.
Encoding format
Individual phonetic spellings of an input word are represented in upper- and lower-case roman characters. Where
there are multiple possible phonetic representations, these are joined with a pipe (|
) character.
If multiple hyphenated words where found, or if the word may contain a name prefix, each encoded word is placed
in elipses and these blocks are then joined with hyphens. For example, "d'ortley
" has a possible
prefix. The form without prefix encodes to ortlaj|ortlej
, while the form with prefix encodes to
dortlaj|dortlej
. Thus, the full, combined encoding is (ortlaj|ortlej)-(dortlaj|dortlej)
.
The encoded forms are often quite a bit longer than the input strings. This is because a single input may have many
potential phonetic interpretations. For example, Renault
encodes to
rYnDlt|rYnalt|rYnult|rinDlt|rinalt|rinult
. The APPROX rules will tend to produce larger
encodings as they consider a wider range of possible, approximate phonetic interpretations of the original word.
Down-stream applications may wish to further process the encoding for indexing or lookup purposes, for example, by
splitting on pipe (|
) and indexing under each of these alternatives.
since 1.6
Properties
Name | Description |
---|---|
IsConcat | Gets or Sets how multiple possible phonetic encodings are combined.
|
NameType | Gets or Sets the name type currently in operation. Use GENERIC unless you specifically want phonetic encodings optimized for Ashkenazi or Sephardic Jewish family names. |
RuleType | Gets or Sets the rule type to apply. This will widen or narrow the range of phonetic encodings considered. APPROX or EXACT for approximate or exact phonetic matches. |
Methods
Name | Description |
---|---|
Encode(String) | |
SetMaxPhonemes(Int32) | Sets the number of maximum of phonemes that shall be considered by the engine. since 1.7 |