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@@ -1,49 +1,75 @@
4. TEXT TO PHONEME TRANSLATION {.western}
------------------------------
# Table of contents
### 4.1 Translation Files {.western}
* [Text to phoneme translation](#text-to-phoneme-translation)
* [Translation Files](#translation-files)
* [Phoneme names](#phoneme-names)
* [Pronunciation Rules](#pronunciation-rules)
* [Rule Groups](#rule-groups)
* [Rules](#rules)
* [Special characters in \<phoneme string\>](#special-characters-in-phoneme-string)
* [Special Characters in both \<pre\> and \<post\> ](#special-characters-in-both-pre-and-post)
* [Special characters only in \<pre\> ](#special-characters-only-in-pre)
* [Special characters only in \<post\> ](#special-characters-only-in-post)
* [Pronunciation Dictionary List](#pronunciation-dictionary-list)
* [Multiple Words](#multiple-words)
* [Special characters in \<phoneme string\>](#special-characters-in-phoneme-string)
* [Flags](#flags)
* [Translating a Word to another Word](#translating-a-word-to-another-word)
* [Conditional Rules](#conditional-rules)
* [Numbers and Character Names](#numbers-and-character-names)
* [Letter names](#letter-names)
* [Numbers](#numbers)
* [Character Substitution](#character-substitution)
# Text to phoneme translation
## Translation Files
There is a separate set of pronunciation files for each language, their
names starting with the language name.
There are two separate methods for translating words into phonemes:
- -
* Pronunciation Rules. These are an attempt to define the pronunciation rules for the language. The source file is:
**\<language\>\_rules** (eg. `en_rules`)
These two files are compiled into the file ***\<language\>\_dict***  in
the espeak-data directory (eg. espeak-data/en\_dict)
* Lookup Dictionary. A list of individual words and their pronunciations and/or various other properties. The source files are:
**\<language\>\_list** (eg. `en_list`) and optionally **\<language\>\_extra**.
### 4.2 Phoneme names {.western}
These two files are compiled into the file **\<language\>\_dict**  in
the espeak-data directory (eg. `espeak-data/en_dict`)
## Phoneme names
Each of the language's phonemes is represented by a mnemonic of 1, 2, 3,
or 4 characters. Together with a number of utility codes (eg. stress
marks and pauses), these are defined in the phoneme data file (see
\*spec not yet available\*).
marks and pauses), these are defined in the phoneme data file (_TODO_).
The utility 'phonemes' are:
+--------------------------------------+--------------------------------------+
| **'** | primary stress |
+--------------------------------------+--------------------------------------+
| **,** | secondary stress |
+--------------------------------------+--------------------------------------+
| **%** | unstressed syllable |
+--------------------------------------+--------------------------------------+
| **=   ** | put the primary stress on the |
| | preceding syllable |
+--------------------------------------+--------------------------------------+
| **\_:** | short pause |
+--------------------------------------+--------------------------------------+
| **\_** | a shorter pause |
+--------------------------------------+--------------------------------------+
| **||** | indicates a word boundary within a |
| | phoneme string |
+--------------------------------------+--------------------------------------+
| **|** | can be used to separate two adjacent |
| | characters, to prevent them from |
| | being considered as a |
| | multi-character phoneme mnemonic |
+--------------------------------------+--------------------------------------+
+-----------+--------------------------------------+
| **'** | primary stress |
+-----------+--------------------------------------+
| **,** | secondary stress |
+-----------+--------------------------------------+
| **%** | unstressed syllable |
+-----------+--------------------------------------+
| **=** | put the primary stress on the |
| | preceding syllable |
+-----------+--------------------------------------+
| **\_:** | short pause |
+-----------+--------------------------------------+
| **\_** | a shorter pause |
+-----------+--------------------------------------+
| **||** | indicates a word boundary within a |
| | phoneme string |
+-----------+--------------------------------------+
| **|** | can be used to separate two adjacent |
| | characters, to prevent them from |
| | being considered as a |
| | multi-character phoneme mnemonic |
+-----------+--------------------------------------+
It is not necessary to specify the stress of every syllable. Stress
markers are only needed in order to change the effect of the language's
@@ -54,9 +80,11 @@ loosely on the Kirshenbaum ascii character representation of the
International Phonetic Alphabet
[www.kirshenbaum.net/IPA/ascii-ipa.pdf](http://www.kirshenbaum.net/IPA/ascii-ipa.pdf)
### 4.3 Pronunciation Rules {.western}
Full list of commonly used phonemes can be found in [phsource/phonemes](../phsource/phonemes) file.
The rules in the ***\<language\>\_rules***  file specify the phonemes
## Pronunciation Rules
The rules in the **\<language\>\_rules**  file specify the phonemes
which are used to pronounce each letter, or sequence of letters. Some
rules only apply when the letter or letters are preceded by, or followed
by, other specified letters.
@@ -68,21 +96,52 @@ matching rule is chosen. The pointer into the source word is then
advanced past those letters which have been matched and the process is
repeated until all the letters of the word have been processed.
#### 4.3.1 Rule Groups {.western}
### Rule Groups
The rules are organized in groups, each starting with a ".group" line:
**.group \<character\>**
> A group for each letter or character.
**.group \<2 characters\>**
> Optional groups for some common 2 letter combinations. This is only needed, for efficiency, in cases where there are many rules for a particular letter. They would not be needed for a language which has regular spelling rules. The first character can only be an ascii character (less than 0x80).
**.group**
> A group for other characters which don't have their own group.
**.L\<nn\>**
> Defines a group of letter sequences, any of which can match with Lnn in a pre or post rule (see below). nn is a 2 digit decimal number in the range 01 to 25. eg:
`.L01 b bl br pl pr`
**.replace**
> See section [Character Substitution](#character-substitution).
When matching a word, firstly the 2-letter group for the two letters at
the current position in the word (if such a group exists) is searched,
and then the single-letter group. The highest scoring rule in either of
those two groups is used.
#### 4.3.2 Rules {.western}
### Rules
Each rule is on separate line, and has the syntax:
`[<pre>)] <match> [(<post>] <phoneme string>`
eg.
```
.group o
o 0 // "o" is pronounced as [0]
oo u: // but "oo" is pronounced as [u:]
b) oo (k U
```
"oo" is pronounced as [u:], but when also preceded by "b" and followed
by "k", it is pronounced [U].
@@ -95,140 +154,142 @@ Alphabetic characters in the \<pre\>, \<match\>, and \<post\> parts must
be lower case, and matching is case-insensitive. Some upper case letters
are used in \<pre\> and \<post\> with special meanings.
#### 4.3.3 Special characters in \<phoneme string\>: {.western}
### Special characters in \<phoneme string\>:
+--------------------------------------+--------------------------------------+
| **\_\^\_\<language code\>   ** | Translate using a different |
| | language. |
+--------------------------------------+--------------------------------------+
#### 4.3.4 Special Characters in both \<pre\> and \<post\>: {.western}
**_^_\<language code\>**
+--------------------------------------+--------------------------------------+
| **\_** | Beginning or end of a word (or a |
| | hyphen). |
+--------------------------------------+--------------------------------------+
| **-** | Hyphen. |
+--------------------------------------+--------------------------------------+
| **A** | Any vowel (the set of vowel |
| | characters may be defined for a |
| | particular language). |
+--------------------------------------+--------------------------------------+
| **C** | Any consonant. |
+--------------------------------------+--------------------------------------+
| **B H F G Y ** | These may indicate other sets of |
| | characters (defined for a particular |
| | language). |
+--------------------------------------+--------------------------------------+
| **L\<nn\>** | Any of the sequence of characters |
| | defined as a letter group (see 4.3.1 |
| | above). |
+--------------------------------------+--------------------------------------+
| **D** | Any digit. |
+--------------------------------------+--------------------------------------+
| **K** | Not a vowel (i.e. a consonant or |
| | word boundary or non-alphabetic |
| | character). |
+--------------------------------------+--------------------------------------+
| **X** | There is no vowel until the word |
| | boundary. |
+--------------------------------------+--------------------------------------+
| **Z** | A non-alphabetic character. |
+--------------------------------------+--------------------------------------+
| **%** | Doubled (placed before a character |
| | in \<pre\> and after it in \<post\>. |
+--------------------------------------+--------------------------------------+
| **/** | The following character is treated |
| | literally. |
+--------------------------------------+--------------------------------------+
> Translate using a different language.
If this rule is selected when translating a word, then the translation is aborted and the word is re-translated using the specified different language. \<language code\> may be upper or lower case. This can be used to recognise certain letter combinations as being foreign words and to use the foreign pronunciation for them. eg:
`th (_ _^_EN`
indicates that a word which ends in "th" is translated using the English translation rules and spoken with English phonemes.
### Special Characters in both \<pre\> and \<post\>
+------------------+--------------------------------------+
| **\_** | Beginning or end of a word (or a |
| | hyphen). |
+------------------+--------------------------------------+
| **-** | Hyphen. |
+------------------+--------------------------------------+
| **A** | Any vowel (the set of vowel |
| | characters may be defined for a |
| | particular language). |
+------------------+--------------------------------------+
| **C** | Any consonant. |
+------------------+--------------------------------------+
| **B H F G Y** | These may indicate other sets of |
| | characters (defined for a particular |
| | language). |
+------------------+--------------------------------------+
| **L\<nn\>** | Any of the sequence of characters |
| | defined as a letter group (see 1 |
| | above). |
+------------------+--------------------------------------+
| **D** | Any digit. |
+------------------+--------------------------------------+
| **K** | Not a vowel (i.e. a consonant or |
| | word boundary or non-alphabetic |
| | character). |
+------------------+--------------------------------------+
| **X** | There is no vowel until the word |
| | boundary. |
+------------------+--------------------------------------+
| **Z** | A non-alphabetic character. |
+------------------+--------------------------------------+
| **%** | Doubled (placed before a character |
| | in \<pre\> and after it in \<post\>. |
+------------------+--------------------------------------+
| **/** | The following character is treated |
| | literally. |
+------------------+--------------------------------------+
The sets of letters indicated by A, B, C, E, F G may be defined
differently for each language.
Examples of rules:
~~~~ {.western}
```
_) a // "a" at the start of a word
a (CC // "a" followed by two consonants
a (C% // "a" followed by a double consonant (the same letter twice)
a (/% // "a" followed by a percent sign
%C) a // "a" preceded by a double consonants
~~~~
```
#### 4.3.5 Special characters only in \<pre\>: {.western}
### Special characters only in \<pre\>:
+--------------------------------------+--------------------------------------+
| **@   ** | Any syllable. |
+--------------------------------------+--------------------------------------+
| **&** | A syllable which may be stressed |
| | (i.e. is not defined as unstressed). |
+--------------------------------------+--------------------------------------+
| **V** | Matches only if a previous word has |
| | indicated that a verb form is |
| | expected. |
+--------------------------------------+--------------------------------------+
+-----------------+--------------------------------------+
| **@** | Any syllable. |
+-----------------+--------------------------------------+
| **&** | A syllable which may be stressed |
| | (i.e. is not defined as unstressed). |
+-----------------+--------------------------------------+
| **V** | Matches only if a previous word has |
| | indicated that a verb form is |
| | expected. |
+-----------------+--------------------------------------+
eg.
~~~~ {.western}
```
@@) bi // "bi" preceded by at least two syllables
@@a) bi // "bi" preceded by at least 2 syllables and following 'a'
~~~~
```
Note, that matching characters in the \<pre\> part do not affect the
syllable counting.
#### 4.3.6 Special characters only in \<post\>: {.western}
### Special characters only in \<post\>
+--------------------------------------+--------------------------------------+
| **@** | A vowel follows somewhere in the |
| | word. |
+--------------------------------------+--------------------------------------+
| **+** | Force an increase in the score in |
| | this rule (may be repeated for more |
| | effect). |
+--------------------------------------+--------------------------------------+
| **S\<number\>  ** | This number of matching characters |
| | are a standard suffix, remove them |
| | and retranslate the word. |
+--------------------------------------+--------------------------------------+
| **P\<number\>** | This number of matching characters |
| | are a standard prefix, remove them |
| | and retranslate the word. |
+--------------------------------------+--------------------------------------+
| **Lnn** | **nn** is a 2-digit decimal number |
| | in the range 01 to 20\ |
| | Matches with any of the letter |
| | sequences which have been defined |
| | for letter group **nn** |
+--------------------------------------+--------------------------------------+
| **N** | Only use this rule if the word is |
| | not a retranslation after removing a |
| | suffix. |
+--------------------------------------+--------------------------------------+
| **\#** | (English specific) change the next |
| | "e" into a special character "E" |
+--------------------------------------+--------------------------------------+
| **\$noprefix** | Only use this rule if the word is |
| | not a retranslation after removing a |
| | prefix. |
+--------------------------------------+--------------------------------------+
| **\$w\_alt\ | Only use this rule if the word is |
| \$w\_alt2\ | found in the \*\_list file with the |
| \$w\_alt3** | **\$alt**, **\$alt2** or **\$alt3** |
| | attribute respectively. |
+--------------------------------------+--------------------------------------+
| **\$p\_alt\ | Only use this rule if the part-word, |
| \$p\_alt2\ | up to and including the pre and |
| \$p\_alt3** | match parts of this rule, is found |
| | in the \*\_list file with the |
| | **\$alt**, **\$alt2** or **\$alt3** |
| | attribute respectively. |
+--------------------------------------+--------------------------------------+
+--------------------+--------------------------------------+
| **@** | A vowel follows somewhere in the |
| | word. |
+--------------------+--------------------------------------+
| **+** | Force an increase in the score in |
| | this rule (may be repeated for more |
| | effect). |
+--------------------+--------------------------------------+
| **S\<number\>** | This number of matching characters |
| | are a standard suffix, remove them |
| | and retranslate the word. |
+--------------------+--------------------------------------+
| **P\<number\>** | This number of matching characters |
| | are a standard prefix, remove them |
| | and retranslate the word. |
+--------------------+--------------------------------------+
| **Lnn** | **nn** is a 2-digit decimal number |
| | in the range 01 to 20\ |
| | Matches with any of the letter |
| | sequences which have been defined |
| | for letter group **nn** |
+--------------------+--------------------------------------+
| **N** | Only use this rule if the word is |
| | not a retranslation after removing a |
| | suffix. |
+--------------------+--------------------------------------+
| **\#** | (English specific) change the next |
| | "e" into a special character "E" |
+--------------------+--------------------------------------+
| **\$noprefix** | Only use this rule if the word is |
| | not a retranslation after removing a |
| | prefix. |
+--------------------+--------------------------------------+
| **\$w\_alt\ | Only use this rule if the word is |
| \$w\_alt2\ | found in the \*\_list file with the |
| \$w\_alt3** | **\$alt**, **\$alt2** or **\$alt3** |
| | attribute respectively. |
+--------------------+--------------------------------------+
| **\$p\_alt\ | Only use this rule if the part-word, |
| \$p\_alt2\ | up to and including the pre and |
| \$p\_alt3** | match parts of this rule, is found |
| | in the \*\_list file with the |
| | **\$alt**, **\$alt2** or **\$alt3** |
| | attribute respectively. |
+--------------------+--------------------------------------+
eg.
~~~~ {.western}
```
@) ly (_S2 lI // "ly", at end of a word with at least one other
// syllable, is a suffix pronounced [lI]. Remove
// it and retranslate the word.
@@ -237,7 +298,7 @@ eg.
// prefix pronounced [Vn]
_) un (i ju: // ... except in words starting "uni"
_) un (inP2 ,Vn // ... but it is for words starting "unin"
~~~~
```
S and P must be at the end of the \<post\> string.
@@ -245,49 +306,49 @@ S\<number\> may be followed by additional letters (eg. S2ei ). Some of
these are probably specific to English, but similar functions could be
made for other languages.
+--------------------------------------+--------------------------------------+
| **q** | query the \_list file to find stress |
| | position or other attributes for the |
| | stem, but don't re-translate the |
| | word with the suffix removed. |
+--------------------------------------+--------------------------------------+
| **t** | determine the stress pattern of the |
| | word **before** adding the suffix |
+--------------------------------------+--------------------------------------+
| **d   ** | the previous letter may have been |
| | doubled when the suffix was added. |
+--------------------------------------+--------------------------------------+
| **e** | "e" may have been removed. |
+--------------------------------------+--------------------------------------+
| **i** | "y" may have been changed to "i." |
+--------------------------------------+--------------------------------------+
| **v** | the suffix means the verb form of |
| | pronunciation should be used. |
+--------------------------------------+--------------------------------------+
| **f** | the suffix means the next word is |
| | likely to be a verb. |
+--------------------------------------+--------------------------------------+
| **m** | after this suffix has been removed, |
| | additional suffixes may be removed. |
+--------------------------------------+--------------------------------------+
+-------+--------------------------------------+
| **q** | query the \_list file to find stress |
| | position or other attributes for the |
| | stem, but don't re-translate the |
| | word with the suffix removed. |
+-------+--------------------------------------+
| **t** | determine the stress pattern of the |
| | word **before** adding the suffix |
+-------+--------------------------------------+
| **d** | the previous letter may have been |
| | doubled when the suffix was added. |
+-------+--------------------------------------+
| **e** | "e" may have been removed. |
+-------+--------------------------------------+
| **i** | "y" may have been changed to "i." |
+-------+--------------------------------------+
| **v** | the suffix means the verb form of |
| | pronunciation should be used. |
+-------+--------------------------------------+
| **f** | the suffix means the next word is |
| | likely to be a verb. |
+-------+--------------------------------------+
| **m** | after this suffix has been removed, |
| | additional suffixes may be removed. |
+-------+--------------------------------------+
P\<number\> may be followed by additonal letters (eg. P3v ).
+--------------------------------------+--------------------------------------+
| **t   ** | determine the stress pattern of the |
| | word **before** adding the prefix |
+--------------------------------------+--------------------------------------+
| **v** | the suffix means the verb form of |
| | pronunciation should be used. |
+--------------------------------------+--------------------------------------+
+--------+--------------------------------------+
| **t** | determine the stress pattern of the |
| | word **before** adding the prefix |
+--------+--------------------------------------+
| **v** | the suffix means the verb form of |
| | pronunciation should be used. |
+--------+--------------------------------------+
### 4.4 Pronunciation Dictionary List {.western}
## Pronunciation Dictionary List
The ***\<language\>\_list***  file contains a list of words whose
The **\<language\>\_list**  file contains a list of words whose
pronunciations are given explicitly, rather than determined by the
Pronunciation Rules. The ***\<language\>\_extra***  file, if present, is
Pronunciation Rules. The **\<language\>\_extra**  file, if present, is
also used and it's contents are taken as coming after those in
***\<language\>\_list***.
**\<language\>\_list**.
Also the list can be used to specify the stress pattern, or other
properties, of a word.
@@ -298,57 +359,59 @@ Dictionary List after the prefix or suffix has been removed.
Lines in the dictionary list have the form:
eg.
```
<word> [<phoneme string>] [<flags>]
```
~~~~ {.western style="margin-bottom: 0.5cm"}
eg.
```
book bUk
~~~~
```
Rather than a full pronunciation, just the stress may be given, to
change where it would be otherwise placed by the Pronunciation Rules:
~~~~ {.western}
```
berlin $2 // stress on second syllable
absolutely $3 // stress on third syllable
for $u // an unstressed word
~~~~
```
#### 4.4.1 Multiple Words {.western}
### Multiple Words
A pronunciation may also be specified for a group of words, when these
appear together. Up to four words may be given, enclosed in brackets.
This may be used for change the pronunciation or stress pattern when
these words occur together,
~~~~ {.western style="margin-bottom: 0.5cm"}
```
(de jure) deI||dZ'U@rI2 // note || used as a word break in the phoneme string
~~~~
```
or to run them together, pronounced as a single word
~~~~ {.western style="margin-bottom: 0.5cm"}
```
(of a) @v@
~~~~
```
or to give them a flag when they occur together
~~~~ {.western style="margin-bottom: 0.5cm"}
```
(such as) sVtS||a2z $pause // precede with a pause
~~~~
```
Hyphenated words in the ***\<language\>\_list***  file must also be
Hyphenated words in the **\<language\>\_list**  file must also be
enclosed within brackets, because the two parts are considered as
separate words.
#### 4.4.2 Special characters in \<phoneme string\>: {.western}
### Special characters in \<phoneme string\>:
+--------------------------------------+--------------------------------------+
| **\_\^\_\<language code\>   ** | Translate using a different |
| | language. See explanation in 4.3.3 |
| **\_\^\_\<language code\>** | Translate using a different |
| | language. See explanation in 3 |
| | above. |
+--------------------------------------+--------------------------------------+
#### 4.4.3 Flags {.western}
### 3 Flags
A word (or group of words) may be given one or more flags, either
instead of, or as well as, the phonetic translation.
@@ -449,12 +512,12 @@ instead of, or as well as, the phonetic translation.
| | end of a sentence. |
+--------------------------------------+--------------------------------------+
| \$abbrev | This has two meanings.\ |
| | 1. If there is no phoneme string: |
| | If there is no phoneme string: |
| | Speak the word as individual |
| | letters, even if it contains a vowel |
| | (eg. "abc" should be spoken as "a" |
| | "b" "c").\ |
| | 2. If there is a phoneme string: |
| | If there is a phoneme string: |
| | This word is capitalized because it |
| | is an abbreviation and |
| | capitalization does not indicate |
@@ -517,35 +580,33 @@ The dictionary list is searched from bottom to top. The first match that
satisfies any conditions is used (i.e. the one lowest down the list). So
if we have:
~~~~ {.western}
```
to t@ // unstressed version
to tu: $atend // stressed version
~~~~
```
then if "to" is at the end of the clause, we get [tu:], if not then we
get [t@].
#### 4.4.4 Translating a Word to another Word {.western}
### Translating a Word to another Word
Rather than specifying the pronunciation of a word by a phoneme string,
you can specify another "sounds like" word.
Use the attribute **\$text** eg.
~~~~ {.western style="margin-bottom: 0.5cm"}
```
cough coff $text
~~~~
```
Alternatively, use the command **\$textmode** on a line by itself to
turn this on for all subsequent entries in the file, until it's turned
off by **\$phonememode**. eg.
~~~~ {.western}
```
$textmode
cough coff
through threw
$phonememode
~~~~
```
This feature cannot be used for the special entries in the **\_list**
files which start with an underscore, such as numbers.
@@ -554,7 +615,7 @@ Currently "textmode" entries are only recognized for complete words, and
not for for stems from which a prefix or suffix has been removed (eg.
the word "coughs" would not match the example above).
### 4.5 Conditional Rules {.western}
## Conditional Rules
Rules in a **\_rules** file and entries in a **\_list** file can be made
conditional. They apply only to some voices. This can be useful to
@@ -569,14 +630,14 @@ line in the [voice file](voices.html).
If the rule starts with   **?!**   then the rule only applies if the
condition number is **not** specified in the voice file. eg.
~~~~ {.western}
```
?3 can't kant // only use this if the voice has: dictrules 3
?!3 rather rA:D3 // only use if the voice doesn't have: dictrules 3
~~~~
```
### 4.6 Numbers and Character Names {.western}
## Numbers and Character Names
#### 4.6.1 Letter names {.western}
### Letter names
The names of individual letters can be given either in the **\_rules**
or **\_list** file. Sometimes an individual letter is also used as a
@@ -585,14 +646,14 @@ letter name. If so, it should be listed in the **\_list** file, preceded
by an underscore, to give the letter name (as distinct from its
pronunciation as a word). eg. in English:
~~~~ {.western style="margin-bottom: 0.5cm"}
```
_a eI
~~~~
```
#### 4.6.2 Numbers {.western}
### Numbers
The operation the TranslateNumber() function is controlled by the
language's `langopts.numbers`{.western} option. This constructs spoken
language's `langopts.numbers` option. This constructs spoken
numbers from fragments according to various options which can be set for
each language. The number fragments are given in the **\_list** file.
@@ -636,7 +697,7 @@ each language. The number fragments are given in the **\_list** file.
| | point. |
+--------------------------------------+--------------------------------------+
### 4.7 Character Substitution {.western}
## Character Substitution
Character substitutions can be specified by using a **.replace**section
at the start of the **\_rules**file. Each line specified either one or
@@ -645,11 +706,11 @@ alphabetic characters. This substitution is done to a word before it is
translated using the spelling-to-phoneme rules. Only the lower-case
version of the characters needs to be specified. eg.
```
  .replace\
    ô   ő   // (Hungarian) allow the use of o-circumflex instead of
o-double-accute\
    ô   ő   // (Hungarian) allow the use of o-circumflex instead of o-double-accute
    û   ű
    cx   ĉ   // (Esperanto) allow "cx" as an alternative to c-circumflex
    fi   fi   // replace a single character ligature by two characters
```