Cobra VAD — C Quick Start

Platforms

• Linux (x86_64)
• macOS (x86_64, arm64)
• Windows (x86_64)
• BeagleBone
• NVIDIA Jetson Nano
• Raspberry Pi (Zero, 2, 3, 4)

Requirements

• C99-compatible compiler
• CMake (3.13+)
• For Windows Only: MinGW is required to build the demo

Picovoice Account & AccessKey

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

Quick Start

Setup

1. Clone the repository:

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

Usage

1. Include the public header files (picovoice.h and pv_cobra.h) .
2. Link the project to an appropriate precompiled library for the target platform and load it.
3. Construct the Cobra object:

static const char* ACCESS_KEY = "${ACCESS_KEY}";

pv_cobra_t *cobra;

const pv_status_t status = pv_cobra_init(
    ACCESS_KEY
    &cobra);

if (status != PV_STATUS_SUCCESS) {
    // error handling logic
}

4. Pass in audio to the pv_cobra_process function:

extern const int16_t *get_next_audio_frame(void);

while (true) {
    const int16_t *pcm = get_next_audio_frame();

    float is_voiced = 0.f;
    const pv_status_t status = pv_cobra_process(cobra, pcm, &is_voiced);
    if (status != PV_STATUS_SUCCESS) {
        // error handling logic
    }
}

5. Release resources explicitly when done with Cobra:

pv_cobra_delete(cobra);

Demo

For the Cobra SDK, we offer demo applications that demonstrate how to use the VAD engine on real-time audio streams (i.e. microphone input) and audio files.

Setup

1. Clone the Cobra repository from GitHub using HTTPS:

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

2. Build the microphone demo:

cd cobra
cmake -S demo/c/. -B demo/c/build
cmake --build demo/c/build --target cobra_demo_mic

Usage

To see the usage options for the demo:

./demo/c/build/cobra_demo_mic

Ensure you have a working microphone connected to your system and run the command corresponding to your platform to detect voice activity:

./demo/c/build/cobra_demo_mic \
-l lib/${PLATFORM}/${ARCH}/libpv_cobra.so \
-a ${ACCESS_KEY} \
-d ${AUDIO_DEVICE_INDEX}

For more information on our Cobra demos for C, head over to our GitHub repository .

Resources