Picovoice Cobra

Requirements

• Node.js Version: 18 or higher.

Supported Platforms

• Linux (x86_64)
• macOS (x86_64, arm64)
• Windows (x86_64, arm64)
• Raspberry Pi (3, 4, 5)

Engine Capabilities

Cobra is an on-device, private, streaming voice activity detection engine that processes all audio locally.

This package contains demo projects specifically designed for Microcontroller Units (MCUs). Currently, it provides support for the following development board:

• STM32F411E-DISCO

The cobra-web-demo demonstrates how to use Cobra in web browsers using the IIFE version of the library (via an HTML <script> tag).

It works by:

1. Instantiating a Cobra worker engine.
2. Using @picovoice/web-voice-processor to access microphone audio and automatically downsample it for the engine.

To run the Android demo, you must provide your AccessKey in the source code. Locate the ACCESS_KEY variable within MainActivity.java and replace its value with your actual key before building the project.

// In MainActivity.java
String ACCESS_KEY = "YOUR_ACCESS_KEY_HERE";

To run the local web demo for Cobra in a browser, follow these steps:

1. Install dependencies using yarn or npm.
2. Run the start script to launch a local web server.
3. Open the URL provided in the terminal output (typically http://localhost:5000) in your browser.
4. Wait for Cobra and the WebVoiceProcessor to initialize. Once ready, speaking will display voice probability on the screen.

# Using yarn
yarn
yarn start

# Using npm
npm install
npm run start

You can install the Cobra iOS binding using either Swift Package Manager (SPM) or CocoaPods.

Swift Package Manager (SPM)

Open your project's Package Dependencies in Xcode and add the following repository URL: https://github.com/Picovoice/cobra.git

CocoaPods

Add the following line to your Podfile:

pod 'Cobra-iOS'

To include Cobra in your Android project, first ensure that mavenCentral() is included in your top-level build.gradle file. Then, add the Cobra dependency to your app's build.gradle file using the following implementation line (replace ${version} with the desired version):

dependencies {
    // ...
    implementation 'ai.picovoice:cobra-android:${version}'
}

Install the Cobra command-line utilities and demos using pip3. These tools allow you to process real-time microphone audio or audio files using the Cobra voice activity detection engine.

sudo pip3 install pvcobrademo

To allow Cobra to access the device microphone, you must add the NSMicrophoneUsageDescription key to your app's Info.plist file with a string explaining why the app needs microphone access.

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

Navigate to demo/web and use yarn or npm to install dependencies and start the development server. Once running, access the demo at http://localhost:5000.

yarn
yarn start

# OR

npm install
npm run start