speech-builder

Utility to build SSML documents for different voice platforms.

Motivation / Approach

Since the major voice platforms all support slightly different subsets of SSML, documents built for one platform often cause errors when used somewhere else.

To address this issue, speech-builder accepts a list of feature flags as configuration option.

Basic Usage

const { ssml } = require('speech-builder');

const s = ssml().add('Hello').emphasis('world');

console.log(s.toString());

<speak>Hello<emphasis>world</emphasis></speak>

API

Table of Contents

• lang
• addText
• addToken
• add
• sub
• phoneme
• break
• audio
• emphasis
• p
• s
• w
• effect
• sayAs
• prosody
• replace

lang

Adds an xml:lang attribute to the current node. If not supported, this is a no-op.

Parameters

• lang string?

addText

Adds text. Characters with special meaning in XML are properly escaped.

Parameters

• text (string | number)

addToken

Like addText but prepends a space (unless it's the first token or the previous one alreads ends with whitespace).

Parameters

• text (string | number)

add

Like addToken but also accepts a function.

Parameters

• content any

sub

Adds a <sub> tag. If substitions are not supported, the alias is added as text instead.

Parameters

• text string
• alias string

phoneme

Adds a <phoneme> tag. When an object with notations in different alphabets is passed as ph, the first one that is supported will be used. For platforms without phoneme support, the special sub alphabet can be used to generate a <sub> tag as fallback.

Parameters

• text string
• ph (string | {})

break

Adds a <break> tag. If not supported, this is a no-op.

Parameters

• time (string? | number)

audio

Adds an <audio> tag. If not supported, the alt text is added as plain text.

Parameters

• src (string | {src: string, alt: string?})

emphasis

Adds an <emphasis> tag. If not supported, the text is added as-is.

Parameters

• content any
• level string?

p

Adds a <p> tag. If not supported, the text is added as-is.

Parameters

• content any

s

Adds an <s> tag. If not supported, the text is added as-is.

Parameters

• content any

w

Adds a <w> tag. If not supported, the text is added as-is.

Parameters

• role string
• content any

effect

Adds an <*:effect> tag. If not supported, the text is added as-is. NOTE: The namespace can be configured via the effect feature setting.

Parameters

• name string
• content any

sayAs

Adds an <say-as> tag. If not supported, the text is added as-is.

Parameters

• interpretAs string
• text (string | number)
• format string?
• detail (string? | number)

prosody

Adds a <prosody> tag. If not supported, the text is added as-is.

Parameters

• attrs Object
• text any

replace

Duck-type as string to support the Jovo framework.

Parameters

• pattern (string | RegExp)
• replacement (string | Function)

Adding variations

const { ssml, random, chance } = require('speech-builder');

ssml()
  .add(random('hello', 'ciao', 'hola', 'salut'))
  .add(chance(0.5, 'beautiful'))
  .add('world');

License

MIT