Overview

You can control how the Syniverse Voice API plays machine-generated text to your users by using a subset of the tags defined in the Speech Synthesis Markup Language (SSML) specification. This XML-based markup enables you to mix multiple languages, provide pronunciation hints for specific words and numbers and control the speed, volume and pitch of synthesized text.

For Syniverse Voice API, you can send SSML Tags as part of the text string. But first, you must surround the entire string in <speak></speak> tags to tell Syniverse that the string includes SSML. You should use escaped double quotes for tag attribute values.

Here is an example of SSML in the body property

    {"body":"<speak>Hello your passcode is 7, 2, 2, 3</speak>"} 

SSML tags

• Breaks: Add breaks (pauses) to spoken text
• Language Voices: Specify the language to use in Text-to-Speech
• Prosody: Set the pitch, speed and volume of the spoken text
• Say as: Provide pronunciation hints for words, numbers and dates
• Sentences and paragraphs: Force the API to recognize sentences and paragraphs when speaking your text
• Substitution: Replace specific text with a pronunciation of your choice”

Breaks

The break tag allows you to add pauses to text. The duration of the pause can be specified either using a strength duration or as a time seconds or milliseconds.

{"body": "<speak>My name is <break time=\"1s\" />John Smith.</speak>"}

Valid strength values include:

• none or x-weak (which removes a pause which might otherwise exist after a full stop)
• weak or medium (equivalent to a comma)
• strong or x-strong (equivalent to a paragraph break)

{"body": "<speak>To be <break strength=\"weak\" />or not to be <break strength=\"weak\"/>that is the question </speak>"}

 

Voice

The Voice tag allows you to control the language used in  Text-to-speech (tts) calls. Voice tag is carried by the "tts:voice" attribute and allows you to select a voice matching the language in which you are composing your message. Voice can be in female or male gender. See available options for Voice below in the Voice/accent & Language section

"options":{"tts:voice":"Penelope"},
 "body":"<speak>Hola, esta es una muestra de una llamada de voz en español</speak>"

Prosody

The prosody tag allows you to set the pitch, rate and volume of the text.

• The volume attribute can be set to the following values: default, silent, x-soft, soft, medium, loud and x-loud. You can also specify a relative decibel value in the form +ndB or -nDB where n is an integer value.
• The rate attribute changes the speed of speech. Acceptable values include: x-slow, slow, medium, fast and x-fast.
• The pitch attribute changes the pitch of the voice. You can specify this using either predefined value labels or numerically. The value labels are: default, x-low, low, medium, high and x-high. The format for specifying a numerical pitch change is: +n% and -n%.

The example below shows how to change the volume, rate and pitch.

{"body": "<speak>I am <prosody volume=\"loud\">loud and proud</prosody>,<prosody rate=\"fast\">quick as a bullet</prosody>and can <prosody pitch=\"x-low\">change my pitch</prosody></speak>"}

Say As

The say-as tag allows you to provide instructions for how particular words and numbers are spoken. Many of these features are automatically detected in speech by the TTS engine, but the say-as command allows you to mark them specifically.

The say-as tag has a required attribute: interpret-as. That attribute must contain one of the following values:

Value of interpret-as	Effect on spoken text
character/spell-out	Spells each letter out, for example: I-A-T-A.
cardinal/number	Pronounces the value as a number. For example, "974" would be pronounced "nine hundred and seventy four".
ordinal	Pronounces the number as an ordinal. For example, "1" would be pronounced "first" and "33" would be pronounced "thirty-third".
digits	Reads the specified numbers out as digits. For example, "747" would be pronounced "seven four seven" and not "seven hundred and forty seven".
fraction	Reads the numbers out as a fraction. For example, "1/3" would be pronounced "one third" and "2 4/10" would be pronounced "two and four tenths".
unit	Reads the specified number out as a unit. The value must be a number followed by a unit of measure with no space between the two. For example: "1meter".
date	Specify how to pronounce dates. See the section below on date formatting below
time	Pronounces time durations in minutes and seconds. For example: 1'30" is read as "one minute and thirty seconds".
address	Reads out a street address with appropriate breaks.
expletive	Replaces the content with a "bleep" to censor expletives. You can use this to automatically substitute filtered swear words.
telephone	Reads out a telephone number with appropriate breaks.

An example:

"body": "<speak>On the <say-as interpret-as=\"ordinal\">1</say-as> day of Christmas,come to <say-as interpret-as=\"address\">123 Main Street</say-as>.<say-as interpret-as=\"spell-out\">RSVP</say-as> for a delicious apple pie.</speak>"

Date formatting

Dates can be formatted in the following ways:

format	How date is read out
mdy	month-date-year (e.g. "3/10/2019")
dmy	day-month-year (e.g. "10/3/2019")
ymd	year-month-day (e.g. "2019/3/10")
md	month-day (e.g. "3/10")
dm	day-month (e.g. "10/3")
ym	year-month (e.g. "2019/3")
my	month-year (e.g. "3/2019")
d	day (e.g. "10")
m	month (e.g. "3")
y	year (e.g. "2019")
yyyymmdd	year-month-day, with optional ? to replace unspecified components. For example: 20190310 or ????0310.

The example below will be converted to "Today is November 15th".

"body": "<speak>Today is <say-as interpret-as=\"date\" format=\"dm\">15/11</say-as></speak>"

Sentences and paragraphs

Sentences

You can wrap sentences in the s tag. This is equivalent to putting a full stop at the end of the sentence.

<"body": "<speak><s>Thank you Kola</s> <s>I will call you later</s></speak>"

Paragraphs

The p tag allows you to specify paragraphs in your speech.

"body": "<speak><p>Hello John</p> 
<p>Can you tell us about yourself</p>
<p>Thank you</p></speak>"

Substitution

The sub tag allows you to provide a substitute pronunciation. The contents of the alias attribute will be read instead.

"body": "<speak>Welcome to the <sub alias=\"United Kingdom\">UK</sub>.</speak>"

 

Voice/Accent & Language Matrix

Below is a list of supported Voice talents and Gender options in different countries for composing your TTS. 

 

Voice	Language Code	Gender	Language Name	SSML Support
Joanna	en-US	female	English-US	Yes
Kendra	en-US	female	English-US	Yes
Kimberly	en-US	female	English-US	Yes
Matthew	en-US	male	English-US	Yes
Amy	en-GB	female	English-British	Yes
Emma	en-GB	female	English-British	Yes
Brian	en-GB	male	English-British	Yes
Geraint	en-GB-WLS	male	English-Welsh	Yes
Nicole	en-AU	female	English-Australian	Yes
Russell	en-AU	male	English-Australian	Yes
Raveena	en-IN	female	English-Indian	Yes
Gwyneth	cy-GB	female	Welsh	Yes
Naja	da-DK	female	Danish	Yes
Mads	da-DK	male	Danish	Yes
Marlene	de-DE	female	German	Yes
Hans	de-DE	male	German	Yes
Conchita	es-ES	female	Spanish-Castilian	Yes
Enrique	es-ES	male	Spanish-Castilian	Yes
Penelope	es-US	female	Spanish-US	Yes
Miguel	es-US	male	Spanish-US	Yes
Chantal	fr-CA	female	French-Canadian	Yes
Celine	fr-FR	female	French	Yes
Mathieu	fr-FR	male	French	Yes
Aditi	hi-IN	female	Hindi	Yes
Dora	is-IS	female	Icelandic	Yes
Karl	is-IS	male	Icelandic	Yes
Carla	it-IT	female	Italian	Yes
Giorgio	it-IT	male	Italian	Yes
Liv	nb-NO	female	Norwegian	Yes
Lotte	nl-NL	female	Dutch	Yes
Ruben	nl-NL	male	Dutch	Yes
Ewa	pl-PL	female	Polish	Yes
Maja	pl-PL	female	Polish	Yes
Jan	pl-PL	male	Polish	Yes
Jacek	pl-PL	male	Polish	Yes
Vitoria	pt-BR	female	Portuguese-Brazilian	Yes
Ricardo	pt-BR	male	Portuguese-Brazilian	Yes
Ines	pt-PT	female	Portuguese-European	Yes
Cristiano	pt-PT	male	Portuguese-European	Yes
Carmen	ro-RO	female	Romanian	Yes
Tatyana	ru-RU	female	Russian	Yes
Maxim	ru-RU	male	Russian	Yes
Astrid	sv-SE	female	Swedish	Yes
Filiz	tr-TR	female	Turkish	Yes
Mizuki	ja-JP	female	Japanese	Yes
Takumi	ja-JP	male	Japanese	Yes
Seoyeon	ko-KR	female	Korean	Yes
Zeina	ar	female	Arabic	Yes
Sin-Ji	yue-CN	female	Cantonese	No
Zhiyu	cmn-CN	female	Chinese	Yes
Tessa	en-ZA	female	South African	No
Carmit	he-IL	female	Israeli-Hebrew	No
Mei-Jia	cmn-TW	female	Taiwanese	No