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

# NVIDIA

> Use the NVIDIA Riva speech-to-text plugin in a Zero Runtime pipeline. Setup and usage in Python.

NVIDIA Riva is a **speech-to-text** plugin that provides GPU-accelerated, low-latency speech
recognition for the caller's audio.

## Setup

Set your NVIDIA API key in the worker environment. Generate a key from the [NVIDIA build portal](https://build.nvidia.com/):

```bash theme={null}
export NVIDIA_API_KEY=<key>
```

## Usage

Import the plugin and pass it to the pipeline's `stt` slot.

```python Python theme={null}
from zrt.plugins import NvidiaSTT

stt = NvidiaSTT()

# Pipeline(stt=stt, ...)
```

## Parameters

| Parameter               | Type          | Default                                                     | Description                                                                                         |
| ----------------------- | ------------- | ----------------------------------------------------------- | --------------------------------------------------------------------------------------------------- |
| `api_key`               | `str \| None` | `None`                                                      | NVIDIA API key. Falls back to the `NVIDIA_API_KEY` environment variable when unset.                 |
| `model`                 | `str`         | `"parakeet-1.1b-en-US-asr-streaming-silero-vad-sortformer"` | Riva/NIM ASR model used for transcription (Parakeet 1.1B with Silero VAD + Sortformer diarization). |
| `server`                | `str`         | `"grpc.nvcf.nvidia.com:443"`                                | Riva gRPC endpoint.                                                                                 |
| `function_id`           | `str`         | `""`                                                        | NVCF function ID for the hosted model.                                                              |
| `language_code`         | `str`         | `"en-US"`                                                   | BCP-47 language tag of the caller's speech.                                                         |
| `sample_rate`           | `int`         | `16000`                                                     | Sample rate (Hz) of the input audio.                                                                |
| `use_ssl`               | `bool`        | `True`                                                      | Use a TLS/SSL gRPC channel.                                                                         |
| `profanity_filter`      | `bool`        | `False`                                                     | Mask profanity in transcripts.                                                                      |
| `automatic_punctuation` | `bool`        | `True`                                                      | Add punctuation to transcripts.                                                                     |

Transcribed text passes to the [LLM](/plugins/llm/google) once
[turn detection](/plugins/turn-detection/namo) decides the caller has finished speaking.