Picovoice.Cheetah 2.1.0

Cheetah Binding for .NET

Cheetah Speech-to-Text Engine

Made in Vancouver, Canada by Picovoice

Cheetah is an on-device streaming speech-to-text engine. Cheetah is:

• Private; All voice processing runs locally.
• Accurate
• Compact and Computationally-Efficient
• Cross-Platform:
  • Linux (x86_64), macOS (x86_64, arm64), and Windows (x86_64)
  • Android and iOS
  • Chrome, Safari, Firefox, and Edge
  • Raspberry Pi (3, 4, 5)

Requirements

• .NET 8.0

Compatibility

Platform compatible with .NET Framework 4.6.1+:

• Windows (x86_64)

Platforms compatible with .NET Core 2.0+:

• Linux (x86_64)
• macOS (x86_64)
• Windows (x86_64)

Platforms compatible with .NET Core 3.0+:

• Raspberry Pi:
  • 3 (32 and 64 bit)
  • 4 (32 and 64 bit)
  • 5 (32 and 64 bit)

Platform compatible with .NET 6.0+:

• macOS (arm64)

Installation

You can install the latest version of Cheetah by getting the latest Cheetah Nuget package in Visual Studio or using the .NET CLI:

dotnet add package Picovoice.Cheetah

AccessKey

Cheetah requires a valid Picovoice AccessKey at initialization. AccessKey acts as your credentials when using Cheetah SDKs. You can get your AccessKey for free. Make sure to keep your AccessKey secret. Signup or Login to Picovoice Console to get your AccessKey.

Usage

Create an instance of the engine and transcribe an audio file:

using Pv;

const string accessKey = "${ACCESS_KEY}";

Cheetah handle = Cheetah.Create(accessKey);

Replace ${ACCESS_KEY} with yours obtained from Picovoice Console.

When initialized, the valid sample rate is given by handle.SampleRate. Expected frame length (number of audio samples in an input array) is handle.FrameLength. The engine accepts 16-bit linearly-encoded PCM and operates on single-channel audio.

short[] GetNextAudioFrame()
{
    // .. get audioFrame
    return audioFrame;
}

string transcript = "";

while(true)
{
    CheetahTranscript transcriptObj = handle.Process(GetNextAudioFrame());
    transcript += transcriptObj.Transcript;

    if (transcriptObj.IsEndpoint) {
        CheetahTranscript finalTranscriptObj = handle.Flush();
        transcript += finalTranscriptObj.Transcript;
    }
}

Cheetah will have its resources freed by the garbage collector, but to have resources freed immediately after use, wrap it in a using statement:

using(Cheetah handle = Cheetah.Create(accessKey))
{
    // .. Cheetah usage here
}

Language Model

The Cheetah .NET SDK comes preloaded with a default English language model (.pv file). Default models for other supported languages can be found in lib/common.

Create custom language models using the Picovoice Console. Here you can train language models with custom vocabulary and boost words in the existing vocabulary.

using Pv;

const string accessKey = "${ACCESS_KEY}";
string modelPath = "/absolute/path/to/model.pv";

Cheetah handle = Cheetah.Create(accessKey, modelPath);

Demos

The Cheetah dotnet demo project is a .NET Core console app that allows for processing real-time audio (i.e. microphone) and files using Cheetah.