Audio Capture

Audio capture is a sensor codelet for capturing audio packets from microphones. The captured audio is published as 32-bit float data.

Configuration Parameters

Parameter Description Default
capture_card_name The name of the audio device used for capturing audio. Leave this empty if using the system’s default capture device.  
sample_rate The sampling rate in Hz for capturing audio. 16000
num_channels The number of audio channels to capture. 6
audio_frame_in_milliseconds The duration of each audio packet in milliseconds. 100
ticks_per_frame Number of times to query ALSA within the duration of 1 audio frame. 5

Messages

Message Proto Type Name
Output AudioDataProto audio_capture

Sample Application

The Audio Capture sample application captures audio from a microphone and saves it to a PCM file as raw audio data. This application requires a microphone connected to the host/device and set as the default audio input device in system settings. The specifications of the connected microphone should be used to configure the audio capture component (num_channels and sample_rate). The application is configured to capture 6 channel audio data at a 16kHz sample rate. This data is captured as 100ms audio packets and saved to /tmp/audio-out-f32-16k.pcm.

Platforms: Desktop, Jetson TX/2, Jetson Xavier, Jetson Nano

Hardware: Any microphone