CMU Pronunciation Dictionary Tools

• Usage
  • Warnings
• VIM Syntax File
• CMU Pronunciation Dictionary File Format
  • Metadata
• File-Based Metadata
  • format
  • metadata
• Phone Table File Format
• Metadata Description File Format
  • CSV Metadata
  • RDF Metadata
• License

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This is a collection of tools for working with the CMU Pronunciation Dictionary.

Usage

The cmudict-tools program has the following command-line structure:

cmudict-tools [OPTIONS] COMMAND DICTIONARY

COMMAND can be one of:

COMMAND	Description
print	Format and optionally sort the dictionary.
validate	Only perform validation checks.

The supported OPTIONS are:

OPTION	Description
-h, --help	Show a help message and exit.
-W WARNING	Enable or disable the specified validation warnings.
--source-accent ACCENT	Use ACCENT to source the dictionary phonesets.
--source-phoneset PHONESET	Use PHONESET to validate the phones in the dictionary.
--accent ACCENT	Use ACCENT to source the outpur phonesets.
--phoneset PHONESET	Use PHONESET to validate the phones in the output.
--format FORMAT	Output the dictionary entries in FORMAT.
--sort SORT	Sort the entries using SORT ordering.
--order-from ORDER_FROM	Start variants at ORDER_FROM, including the initial entry.
--help-warnings	List the available validation warnings.
--input-encoding ENCODING	Use ENCODING to read the dictionary file in (e.g. latin1).
--output-encoding ENCODING	Use ENCODING to print the entries in (e.g. latin1).

The supported DICTIONARY (input) and FORMAT (output) values are:

Format	Input	Output	Description
cmudict	yes	yes	The current dictionary format as maintained by Alex Rudnicky (versions 0.7a and later).
cmudict-weide	yes	yes	The old dictionary format as maintained by Robert L. Weide and others (versions 0.1 through 0.7).
cmudict-new	yes	yes	The dictionary format as maintained by Nikolay V. Shmyrev.
festlex	yes	yes	The festival lexicon format for Scheme (*.scm) files.
json	no	yes	JSON formatted entries and validation errors.

The supported ACCENT values are:

• en-US to use the American English phone table;
• en-GB-x-rp to use the Received Pronunciation British English phone table;
• a CSV file to use phonesets defined in that CSV file (see Phone Table File Format for a description of this file format).

The supported PHONESET values depend on the phone table used. For the en-US and en-GB-x-rp phone tables defined by cmudict-tools, the supported phonesets are:

Phoneset	en-US	en-GB-x-rp	Description
arpabet	yes	yes	An expanded Arpabet-based phoneset.
cepstral	yes	yes	The phoneset used by the Cepstral Text-to-Speech program.
cmu	yes	no	The phoneset used by the official cmudict dictionary.
festvox	yes	no	The phoneset used by the festlex-cmu dictionary.
ipa	yes	yes	Use an IPA (International Phonetic Alphabet) transcription.
timit	yes	no	The phoneset used by the TIMIT database.

The supported SORT values are:

• air to use the new-style sort order (group variants next to their root entry);
• none to leave the entries in the order they are in the dictionary;
• weide to use the old-style sort order (simple ASCII character ordering).

Warnings

The following values are available for the -W option:

Warning	Description
context-ordering	Check context values are ordered sequentially.
context-values	Check context values are numbers.
duplicate-entries	Check for matching entries (word, context, pronunciation).
duplicate-pronunciations	Check for duplicated pronunciations for an entry.
entry-spacing	Check spacing between word and pronunciation.
invalid-phonemes	Check for invalid phonemes.
missing-stress	Check for missing stress markers.
phoneme-spacing	Check for a single space between phonemes.
trailing-whitespace	Check for trailing whitespaces.
unsorted	Check if a word is not sorted correctly.
word-casing	Check for consistent word casing.

If -Wwarn is used, the option is enabled. If -Wno-warn is used, the option is disabled.

The following values have a special behaviour, and cannot be used with the no- prefix:

Warning	Description
all	Enable all warnings.
none	Disable all warnings.

The order is important, as the warning set is tracked incrementally. This allows things like the following combinations:

Example	Description
-Wnone -Winvalid-phonemes	Only use the invalid-phonemes warning.
-Wall -Wno-missing-stress	Use all warnings except missing-stress.

VIM Syntax File

The cmudict-tools project provides a syntax highlighting file for cmudict-style dictionaries.

You can install the files to a VIM install by running:

make VIMDIR=<path-to-vim> vim

Alternatively, if your system supports VIM addons (e.g. Debian Linux), you can install the files by running:

make vim_plugin

which installs the files to /usr/share/vim. If the addon files are not in this location, you need to point VIMDIR to the addons directory and VIMPLUGINDIR to the registry directory.

Once installed, it will automatically highlight files named cmudict. You can explicitly enable highlighting by using the VIM command:

set ft=cmudict

The following variables are supported:

Variable	Default Value	Description
cmudict_accent	en-US	The accent the dictionary is specified in.
cmudict_phoneset	cmu	The phoneset used to transcribe the phones in.
cmudict_format	air	The specific format of the dictionary.

The valid cmudict_accent and cmudict_phoneset values are:

cmudict_phoneset	cmudict_accent="en-US"	cmudict_accent="en-GB-x-rp"
arpabet	yes	yes
cepstral	yes	yes
cmu	yes	no
festvox	yes	no
timit	yes	no

The valid cmudict_format values are:

cmudict_format	Description
air	The current dictionary format as maintained by Alex Rudnicky (versions 0.7a and later).
weide	The old dictionary format as maintained by Robert L. Weide and others (versions 0.1 through 0.7).
new	The dictionary format as maintained by Nikolay V. Shmyrev.

NOTE: You need to set the variables before setting the filetype. For example:

let cmudict_phoneset="arpabet"
set ft=cmudict

CMU Pronunciation Dictionary File Format

A line comment starts with ;;; and spans until the end of the current line. In the cmudict-weide format, a line comment starts with ##.

An entry has the form ENTRY PRONUNCIATION, where ENTRY consists of WORD for the primary entry for the word, or WORD(VARIANT) for an alternate entry. The ENTRY and PRONUNCIATION are separated by two space ( ) characters and ENTRY is in upper case. In the cmudict-new format, ENTRY and PRONUNCIATION are separated by a single space ( ) character and ENTRY is in lower case.

The VARIANT consists of a number from 1 to 9 that denotes an alternate entry. These are numbered consecutively from 1 in the current cmudict format and from 2 in the cmudict-weide and cmudict-new formats.

The PRONUNCIATION section consists of Arpabet-based phones separated by a single space ( ). The casing of the phones depends on the phoneset being used. The vowels have an additional stress marker, which can be:

• 0 for an unstressed vowel;
• 1 for a primary stressed vowel;
• 2 for a secondary stressed vowel.

An entry may have a comment. These comments start with # and span to the end of the line.

NOTE: The various releases of the cmudict contain various formatting errors in several entries, where those entries deviate from the format described here. These will show up as validation warnings when those dictionary versions are run through cmudict-tools with the appropriate validation warnings enabled.

Metadata

Metadata is not supported in the official CMU dictionary format. However, the cmudict-tools project interprets specifically formatted comments as metadata. This allows additional information to be provided in a way that is compatible with existing cmudict tools.

Metadata occurs in line comments for file-based metadata, or entry comments for entry-based metadata. The metadata section of the comment starts and ends with @@. The @@ must be at the start of the comment (i.e. no spaces or other characters) for it to be recognised as metadata. Any text after the metadata is treated as a regular comment.

The content within the metadata block is a sequence of space-separated key=value pairs. A key can occur multiple times, in which case the key will have both values.

File-Based Metadata

This is metadata on line comments in the given dictionary format. This metadata is used to control the cmudict-tools behaviour.

format

The format metadata key overrides the auto-detected file format. It only applies to the cmudict-based formats.

metadata

The metadata metadata key points to a metadata description file containing the valid (key,value) pairs for entry-based metadata.

To test the (key,value) extraction for a metadata description file, you can run:

python metadata.py <metadata-description-file>

This will output JSON text, for example:

{"key1": ["value1", "value2"], "key2": ["value3"]}

Phone Table File Format

This is a CSV document with the first line containing the titles of each field. At a minimum, it needs to support the following fields:

• Arpabet is the phone using an upper-case Arpabet transcription, excluding the stress marker;
• Normalized is the optional canonical form for phonesets that use a different transcription for a given phone;
• IPA is the International Phonetic Alphabet (IPA) transcription for the phone excluding stress markers;
• Type is the phone type (see below) of the given phone;
• Phone Sets is a semi-colon (;) separated list of phonesets that support this phone.

The supported values for the Type field are:

• vowel to indicate a phone that can have a stress marker;
• consonant to indicate a phone that cannot have a stress marker;
• schwa to indicate a phone that can either have no stress marker, or the unstressed (0) stress marker.

For example:

Arpabet,Normalized,IPA,Type,Phone Sets
AA,,ɑ,vowel,arpabet;ipa;cmu;festvox;cepstral;timit
AE,,æ,vowel,arpabet;ipa;cmu;festvox;cepstral;timit

Metadata Description File Format

File Type	Metadata Format
CSV	CSV Metadata
Turtle	RDF Metadata
RDF/XML	RDF Metadata
N-Triples	RDF Metadata

NOTE: The Turtle and RDF/XML formats require the rapper command-line application. This is so those formats can be converted to the N-Triple format.

CSV Metadata

This is a CSV document with the first line containing the titles of each field. At a minimum, it needs to support the following fields:

• Key is the metadata key;
• Value is an allowed value for the metadata key.

For example:

Key,Value
key1,value1
...
keyN,valueN

RDF Metadata

This is an RDF document using the SKOS ontology.

A key is defined as a skos:ConceptScheme and a value as a skos:Concept. The labels are defined using skos:prefLabel predicates. A value is associated with a key using the skos:inScheme predicate. All other metadata triples are ignored.

For example, to support key=value a minimal RDF Turtle file is:

@prefix skos: <http://www.w3.org/2004/02/skos/core#> .

<#> a skos:ConceptScheme ; skos:prefLabel "key" .

<#val> a skos:Concept ; skos:prefLabel "value" ; skos:inScheme <#> .

License

The CMU Pronunciation Dictionary Tools are released under the GPL version 3 or later license.

Copyright (C) 2015 Reece H. Dunn