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Koala Noise Suppression Engine
C Quick Start

Platforms

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

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/koala.git

Usage

  1. Include the public header files (picovoice.h and pv_koala.h).
  2. Link the project to an appropriate precompiled library for the target platform and load it.
  3. Construct the Koala Noise Suppression object:
static const char* ACCESS_KEY = "${ACCESS_KEY}";
static const char* MODEL_PATH = "${MODEL_PATH}";
pv_koala_t *koala;
const pv_status_t status = pv_koala_init(
access_key,
model_path,
&koala);
if (status != PV_STATUS_SUCCESS) {
// error handling logic
}
  1. Pass in audio to the pv_koala_process function:
extern const int16_t *get_next_audio_frame(void);
const int32_t frame_length = pv_koala_frame_length();
int16_t *enhanced_pcm = (int16_t *) malloc(frame_length * sizeof(int16_t));
while (true) {
const int16_t *pcm = get_next_audio_frame();
const pv_status_t status = pv_koala_process(handle, pcm, enhanced_pcm);
if (status != PV_STATUS_SUCCESS) {
// error handling logic
}
}
free(enhanced_pcm);
  1. Release resources explicitly when done with Koala Noise Suppression:
pv_koala_delete(koala);

Demo

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

Setup

  1. Clone the Koala Noise Suppression repository from GitHub using HTTPS:
git clone --recurse-submodules https://github.com/Picovoice/koala.git
  1. Build the microphone demo:
cd koala
cmake -S demo/c/. -B demo/c/build
cmake --build demo/c/build --target koala_demo_mic

Usage

To see the usage options for the demo:

./demo/c/build/koala_demo_mic

Ensure you have a working microphone connected to your system and run the following command to record microphone input, remove noise, and write the cleaned audio to a file:

./demo/c/build/koala_demo_mic \
-l lib/${PLATFORM}/${ARCH}/libpv_koala.${LIB_EXTENSION} \
-m lib/common/koala_params.pv \
-a ${ACCESS_KEY} \
-d ${AUDIO_DEVICE_INDEX} \
-o ${WAV_OUTPUT_PATH}

For more information on our Koala Noise Suppression demos for C, head over to our GitHub repository.

Resources

API

  • Koala Noise Suppression C API Docs

GitHub

  • Koala Noise Suppression C Demos on GitHub

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