Metaphone-ts

A fast implementation of Lawrence Philips Metaphone Algorithm with some additional tweaks

What is the Metaphone Algorithm?

The Metaphone Algorithm is an algorithm used to break words into the individual sounds that make up their pronunciation.

This implementation of the algorithm is quite fast, taking approx. 380 nanoseconds per word according to deno bench

Use Cases

The Metaphone Algorithm is useful for doing fuzzy-word searching, for example, “write” and “right” both return the same result from the metaphone algorithm since they are pronounced the same way.

The Metaphone also can be used in TTS applications such as SAM

Exports

main.ts exports metaphone which takes in one word and returns an Array<String> of phonemes.

The list of possible phonemes is as follows:

A
E
I
O
U
B
X
S
K
J
T
F
H
L
M
N
P
R
0 – theta - the th sound
W
Y

Vowels (other than Y) will only show up in the results if they are the first letter

Import

Node / Frontend

yarn add metaphone-ts

Deno

import {metaphone} from 'https://deno.land/x/metaphone-ts/mod.ts'

Example

import { metaphone } from 'metaphone-ts'

let sounds = metaphone("charlatan")

console.log(sounds) // Prints `[ "X", "R", "L", "T", "N" ]`

The Original Metaphone Algorithm

Metaphone Algorithm

   Created by Lawrence Philips (location unknown). Metaphone presented
   in article in "Computer Language" December 1990 issue.

             *********** BEGIN METAPHONE RULES ***********

 Lawrence Philips' RULES follow:

 The 16 consonant sounds:
                                             |--- ZERO represents "th"
                                             |
      B  X  S  K  J  T  F  H  L  M  N  P  R  0  W  Y

 Exceptions:

   Beginning of word: "ae-", "gn", "kn-", "pn-", "wr-"  ----> drop first letter
                      "Aebersold", "Gnagy", "Knuth", "Pniewski", "Wright"

   Beginning of word: "x"                                ----> change to "s"
                                      as in "Deng Xiaopeng"

   Beginning of word: "wh-"                              ----> change to "w"
                                      as in "Whalen"

 Transformations:

   B ----> B      unless at the end of word after "m", as in "dumb", "McComb"

   C ----> X      (sh) if "-cia-" or "-ch-"
           S      if "-ci-", "-ce-", or "-cy-"
                  SILENT if "-sci-", "-sce-", or "-scy-"
           K      otherwise, including in "-sch-"

   D ----> J      if in "-dge-", "-dgy-", or "-dgi-"
           T      otherwise

   F ----> F

   G ---->        SILENT if in "-gh-" and not at end or before a vowel
                            in "-gn" or "-gned"
                            in "-dge-" etc., as in above rule
           J      if before "i", or "e", or "y" if not double "gg"
           K      otherwise

   H ---->        SILENT if after vowel and no vowel follows
                         or after "-ch-", "-sh-", "-ph-", "-th-", "-gh-"
           H      otherwise

   J ----> J

   K ---->        SILENT if after "c"
           K      otherwise

   L ----> L

   M ----> M

   N ----> N

   P ----> F      if before "h"
           P      otherwise

   Q ----> K

   R ----> R

   S ----> X      (sh) if before "h" or in "-sio-" or "-sia-"
           S      otherwise

   T ----> X      (sh) if "-tia-" or "-tio-"
           0      (th) if before "h"
                  silent if in "-tch-"
           T      otherwise

   V ----> F

   W ---->        SILENT if not followed by a vowel
           W      if followed by a vowel

   X ----> KS

   Y ---->        SILENT if not followed by a vowel
           Y      if followed by a vowel

   Z ----> S