Note
Please see Azure Cognitive Services for Speech documentation for the latest supported speech solutions.
Microsoft Speech Platform
American English Phoneme Representation
The information in this topic is provided only for reference. We recommend that you do not use the SAPI Phone Set to specify pronunciations for any languages in your applications. Instead, use the Universal Phone Set (UPS) for ISpGrammarBuilder grammars and the Speech Platform will automatically perform conversion to SAPI Phone Set for legacy languages, as required. See Legacy SAPI Phone Sets for more information.
Symbolic and Numerical Representation
Application developers can create pronunciations for words in the English language that are not currently in the lexicon by using the English phones, represented in the following table, from the SAPI Phone Set. Each phone describes a unique sound of speech. Each phone has a label (the letters and/or characters that make up the phone), and a numerical identifier (the PhoneID that corresponds to each label).
You can use the SAPI Phone Set to create custom pronunciations in grammars to customize speech recognition, and in TTS prompts to customize synthesized speech output, or in lexicons that may be used for either speech recognition or TTS.
The following is an example entry in an XML-format grammar that conforms to the Speech Recognition Grammar Specification (SRGS) Version 1.0 and specifies a pronunciation for the word "hello":
<token sapi:pron="h eh l ow"/> hello </token>
For improved accuracy, you can add the primary (1), secondary (2) stress markers, and the syllabic markers (-) to the pronunciation.
The following is an example entry in an XML-format TTS prompt that conforms to the Speech Synthesis Markup Language (SSML) Version 1.0 and specifies a pronunciation for the word "hello" using the primary stress (1) and syllabic (-) markers:
<phoneme alphabet="x-microsoft-sapi" ph="h eh - l ow 1"> hello </phoneme>
American English Phoneme Table
| Phone Label | Example | PhoneID |
|---|---|---|
| - | syllable boundary (hyphen) | 1 |
| ! | Sentence terminator (exclamation mark) | 2 |
| & | word boundary | 3 |
| , | Sentence terminator (comma) | 4 |
| . | Sentence terminator (period) | 5 |
| ? | Sentence terminator (question mark) | 6 |
| _ | Silence (underscore) | 7 |
| 1 | Primary stress | 8 |
| 2 | Secondary stress | 9 |
| aa | father | 10 |
| ae | cat | 11 |
| ah | cut | 12 |
| ao | dog | 13 |
| aw | foul | 14 |
| ax | ago | 15 |
| ay | bite | 16 |
| b | big | 17 |
| ch | chin | 18 |
| d | dig | 19 |
| dh | then | 20 |
| eh | pet | 21 |
| er | fur | 22 |
| ey | ate | 23 |
| f | fork | 24 |
| g | gut | 25 |
| h | help | 26 |
| ih | fill | 27 |
| iy | feel | 28 |
| jh | joy | 29 |
| k | cut | 30 |
| l | lid | 31 |
| m | mat | 32 |
| n | no | 33 |
| ng | sing | 34 |
| ow | go | 35 |
| oy | toy | 36 |
| p | put | 37 |
| r | red | 38 |
| s | sit | 39 |
| sh | she | 40 |
| t | talk | 41 |
| th | thin | 42 |
| uh | book | 43 |
| uw | too | 44 |
| v | vat | 45 |
| w | with | 46 |
| y | yard | 47 |
| z | zap | 48 |
| zh | pleasure | 49 |
Please see Legacy SAPI Phone Sets for information on other phone sets.