Cheetah Speech-to-Text
Flutter Quick Start

Platforms

• Flutter (2.8.1+)
• Android (5.0+, API 21+)
• iOS (9.0+)

Requirements

• Flutter SDK
• Android SDK (21+)
• JDK (8+)
• Xcode (9+)

Picovoice Account & AccessKey

Signup or Login to Picovoice Console to get your AccessKey. Make sure to keep your AccessKey secret.

Quick Start

Setup

1. Install Flutter SDK.

2. Run flutter doctor to determine any missing requirements.

3. Add the Cheetah plugin to your app project by referencing it in pubspec.yaml:

dependencies:
  cheetah_flutter: ^<version>

4. Enable the proper permissions for recording with the hardware's microphone on both iOS and Android:

<key>NSMicrophoneUsageDescription</key>
<string>[Permission explanation]</string>

<uses-permission android:name="android.permission.RECORD_AUDIO"/>
<uses-permission android:name="android.permission.INTERNET"/>

Cheetah Model File Integration

Add the Cheetah model file to your Flutter application:

1. Create a model in Picovoice Console or use the default model.
2. Add the model file to an assets folder in your project directory.
3. Add the asset to your pubspec.yaml:

flutter:
  assets:
    - assets/cheetah_model.pv

4. In this example, the path to the model file in code would then be as follows:

String modelPath = "assets/cheetah_model.pv";

Usage

An instance of Cheetah is created by passing a model file path into its static constructor create:

import 'package:cheetah_flutter/cheetah.dart';

String accessKey = '{ACCESS_KEY}'  // AccessKey obtained from Picovoice Console (https://console.picovoice.ai/)
String modelPath = '{CHEETAH_MODEL_PATH}' // path relative to the assets folder or absolute path to file on device

void createCheetah() async {
    try{
        _cheetah = await Cheetah.create(accessKey, modelPath);
    } on CheetahException catch (err) {
        // handle Cheetah init error
    }
}

Transcribe audio:

List<int> buffer = getAudioFrame();

String transcript = "";

while true {
    CheetahTranscript partialResult = await _cheetah.process(getAudioFrame());
    transcript += partialResult.transcript;

    if (partialResult.isEndpoint) {
        CheetahTranscript finalResult = await _cheetah.flush();
        transcript += finalResult.transcript;
    }
}

When done, resources have to be released explicitly:

cheetah.delete();

Demo

For the Cheetah Flutter SDK, we offer demo applications that demonstrate how to use the Speech-to-Text engine on audio recordings.

Setup

Clone the Cheetah repository from GitHub using HTTPS:

git clone --recurse-submodules https://github.com/Picovoice/cheetah.git

Usage

1. Replace {YOUR_ACCESS_KEY_HERE} with a valid AccessKey in the demo/flutter/lib/main.dart file:

2. Copy assets:

cd cheetah/demo/flutter
bash copy_assets.sh

NOTE: on Windows, Git Bash or another bash shell is required, or you will have to manually copy the cheetah demo model file

3. Build and deploy the demo to your device:

flutter run

For more information on our Cheetah demos for Flutter, head over to our GitHub repository.

Resources