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Usage guide

Setup, environment variables, and Python/JavaScript/Go usage examples.

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NvidiaTTS

Neural text-to-speech via NVIDIA Riva / NIM. GPU-accelerated synthesis using Riva voices (e.g. Magpie multilingual / RAD-TTS), with streaming output.

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Constructor

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api_key
str | None
NVIDIA API key. Falls back to NVIDIA_API_KEY.
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voice
str
default:"English-US-Female-1"
Riva voice name, e.g. "English-US-Female-1" or a Magpie voice like "Magpie-Multilingual.EN-US.Mia". Default "English-US-Female-1".
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language_code
str
default:"en-US"
BCP-47 language tag. Default "en-US".
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sample_rate
int
default:"22050"
Output rate in Hz. Default 22050.
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server
str
default:""
Riva gRPC endpoint. Default "".

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aclose

Release any resources held by the provider.

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emit

Emit an event, invoking all registered handlers with the given arguments. Handlers are called in registration order. Coroutine handlers are scheduled on the running event loop. If the emitter is closed, the call is a no-op.
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event
T
required
The event to emit.

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interrupt

Interrupt and cancel the current synthesis for the active session, if any.

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off

Remove a previously registered handler for an event. If the handler is not registered for the event, the call is a no-op.
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event
T
required
The event the handler was registered for.
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callback
Callable[..., Any]
required
The handler to remove.

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on

Register a handler for an event. Can be used directly by passing a callback, or as a decorator when callback is omitted.
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event
T
required
The event to listen for.
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callback
Callable[..., Any] | None
The handler to invoke when the event is emitted. If None, a decorator is returned that registers the decorated function.
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returns
Callable[..., Any]
The registered callback when callback is provided, otherwise a decorator that registers and returns the function it wraps.

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on_first_audio_byte

Register the callback invoked when the first audio byte is produced.
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callback
'Callable[[int, int], Awaitable[None] | None]'
required
A callable, optionally async, invoked with synthesis timing information when the first audio byte is emitted.

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synthesize

Synthesize the given text into speech. Implementations should convert the text to audio. The default behavior forwards the text to the active session for playback when one is present.
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text
Any
required
The text to synthesize; coerced to a string if needed.