> ## Documentation Index
> Fetch the complete documentation index at: https://docs.reverieinc.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Key Features

### `ssml` Tags

The SSML input to synthesize an audio output. If you want to follow W3 standards, the ssml field must be used and not the text field. Refer [here](/usage-guides/text-to-speech/ssml-tags) to know more about SSML Inputs.

| SSML Tag    | Description                                                                     |
| ----------- | ------------------------------------------------------------------------------- |
| `<prosody>` | Controls the pitch, rate, and volume of speech.                                 |
| `<say-as>`  | Defines how the enclosed text should be spoken (e.g., as a number, date, etc.). |
| `<sub>`     | Substitutes one word or phrase for another when speaking.                       |
| `<break>`   | Adds a pause in speech for a specified duration.                                |
| `<p>`       | Indicates a paragraph break, resulting in a pause.                              |
| `<s>`       | Represents a sentence break, adding a pause.                                    |
| `<speak>`   | The root tag that defines the speech content.                                   |
| `<voice>`   | Specifies which voice to use for speech (e.g., male, female).                   |

### `speed`

The speech rate of the audio file. Allows values: from 0.5 (slowest speed rate) up to 1.5 (fastest speed rate). Note: By default, speed = 1 (normal speed).

**For Example**:

<CodeGroup>
  ```bash cURL  theme={null}
  curl --location --request POST 'https://revapi.reverieinc.com/' \
  --header 'REV-API-KEY: <YOUR API KEY>' \
  --header 'REV-APP-ID: <YOUR APP-ID>' \
  --header 'REV-APPNAME: tts' \
  --header 'speaker: hi_female' \
  --header 'Content-Type: application/json' \
  --data-raw '{
  	"text": ["भारत मेरा देश है। मेरी कंपनी का नाम रेवेरी लैंग्वेज टेक्नोलॉजीज है।" ], 
  	"speed": 1, 
  }'
  ```

  ````
  </CodeGroup>

  ### `pitch` 
  Speaking pitch, in the range Allows values: from -3 up tp 3. 3 indicates an increase of 3 semitones from the original pitch. -3 indicates a decrease of 3 semitones from the original pitch. Note: By default, the pitch = 0 (zero)

  **For Example**: 
  <CodeGroup>
  ```bash cURL
  curl --location --request POST 'https://revapi.reverieinc.com/' \
  --header 'REV-API-KEY: <YOUR API KEY>' \
  --header 'REV-APP-ID: <YOUR APP-ID>' \
  --header 'REV-APPNAME: tts' \
  --header 'speaker: hi_female' \
  --header 'Content-Type: application/json' \
  --data-raw '{
  	"text": ["भारत मेरा देश है। मेरी कंपनी का नाम रेवेरी लैंग्वेज टेक्नोलॉजीज है।" ], 
  	"pitch": -3, 
  }'
  ````
</CodeGroup>

### `sample_rate`

The sampling rate (in hertz) to synthesize the audio output. Refer to [Supporting Sampling Rate](/usage-guides/text-to-speech/supported-sampling-rates), to know the supporting audio sample rates. Note: By default, the sample\_rate = 22050 Hz (22.05kHz)

**For Example**:

<CodeGroup>
  ```bash cURL  theme={null}
  curl --location --request POST 'https://revapi.reverieinc.com/' \
  --header 'REV-API-KEY: <YOUR API KEY>' \
  --header 'REV-APP-ID: <YOUR APP-ID>' \
  --header 'REV-APPNAME: tts' \
  --header 'speaker: hi_female' \
  --header 'Content-Type: application/json' \
  --data-raw '{
  	"text": ["भारत मेरा देश है। मेरी कंपनी का नाम रेवेरी लैंग्वेज टेक्नोलॉजीज है।" ], 
  	"sample_rate": 22050, 
  }'
  ```
</CodeGroup>

### `format`

The speech audio format to generate the audio file. Refer to [Supporting Audio Formats](/usage-guides/text-to-speech/supported-audio-formats), to know the supporting audio formats. Note: By default, the format = WAV

**For Example**:

<CodeGroup>
  ```bash cURL  theme={null}
  curl --location --request POST 'https://revapi.reverieinc.com/' \
  --header 'REV-API-KEY: <YOUR API KEY>' \
  --header 'REV-APP-ID: <YOUR APP-ID>' \
  --header 'REV-APPNAME: tts' \
  --header 'speaker: hi_female' \
  --header 'Content-Type: application/json' \
  --data-raw '{
  	"text": ["भारत मेरा देश है। मेरी कंपनी का नाम रेवेरी लैंग्वेज टेक्नोलॉजीज है।" ], 
  	"format": wav, 
  }'
  ```
</CodeGroup>