leopard_flutter 1.0.2

A Flutter plugin for Picovoice's Leopard Speech-to-Text engine

Leopard Binding for Flutter

Leopard Speech-to-Text Engine

Made in Vancouver, Canada by Picovoice

Leopard is an on-device speech-to-text engine. Leopard is:

• Private; All voice processing runs locally.
• Accurate [1]
• Compact and Computationally-Efficient [2]
• Cross-Platform:
  • Linux (x86_64)
  • macOS (x86_64, arm64)
  • Windows (x86_64)
  • Android
  • iOS
  • Raspberry Pi (4, 3)
  • NVIDIA Jetson Nano

Compatibility

This binding is for running Leopard on Flutter 1.20.0+ on the following platforms:

• Android 4.4+ (API 19+)
• iOS 9.0+

Installation

To start, you must have the Flutter SDK installed on your system. Once installed, you can run flutter doctor to determine any other missing requirements.

To add the Leopard plugin to your app project, you can reference it in your pub.yaml:

dependencies:
  leopard_flutter: ^<version>

AccessKey

Leopard requires a valid Picovoice AccessKey at initialization. AccessKey acts as your credentials when using Leopard 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.

Permissions

To enable recording with the hardware's microphone, you must first ensure that you have enabled the proper permission on both iOS and Android.

On iOS, open your Info.plist and add the following line:

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

On Android, open your AndroidManifest.xml and add the following line:

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

Leopard Model File Integration

Add the Leopard model file to your Flutter application by:

1. Either creating a model in Picovoice Console or using the default model in /lib/common/leopard_params.pv.
2. Add the model file to an assets folder in your project directory.
3. Then add it to your pubspec.yaml:

flutter:
  assets:
    - assets/leopard_model.pv

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

String modelPath = "assets/leopard_model.pv";

Usage

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

import 'package:leopard_flutter/leopard.dart';

const accessKey = "{ACCESS_KEY}"  // AccessKey obtained from Picovoice Console (https://console.picovoice.ai/)

void createLeopard() async {
    try {
        _leopard = await Leopard.create(accessKey, '{LEOPARD_MODEL_PATH}');
    } on LeopardException catch (err) {
        // handle Leopard init error
    }
}

Transcribe an audio file by passing in the path:

try {
    String transcript = = await _leopard.processFile("${AUDIO_FILE_PATH}");
} on LeopardException catch (err) { }

When done resources have to be released explicitly:

leopard.delete();

Demo App

For example usage refer to our Flutter demo application.