Audio Interface

Introduction

The gnuradio audio component provides gr::audio::source and gr::audio::sink blocks. The audio blocks stream floating point samples to and from audio hardware.

The gr-audio component will be built automatically when gnuradio-runtime is enabled. Support for underlying audio architectures depends on OS and installed libraries. At the time of writing, gr-audio supports OSS, ALSA, Jack, Portaudio, Audiounit, and Winmm.

At runtime, gr-audio will automatically select from the available architectures. The user can override the selection via configuration file by setting "audio_module" to one of the following strings:

• oss
• alsa
• jack
• portaudio
• osx
• windows

See gr-audio.conf for an example.

Import this package with:

    from gnuradio import audio

See the Doxygen documentation for details about the blocks available in this package. A quick listing of the details can be found in Python after importing by using:

    help(audio)

Usage

For an audio source, a typical OptionParser option and it's use looks like:

    parser.add_option("-O", "--audio-output", type="string", default="",
                       help="pcm device name.  E.g., hw:0,0 or surround51 or /dev/dsp")
    audio_rate = 32e3
    audio_sink = audio.sink (int (audio_rate), options.audio_output)

Similarly, an audio sink would have a typical OptionParser option and its use would look like:

    parser.add_option("-I", "--audio-input", type="string", default="",
                      help="pcm input device name.  E.g., hw:0,0 or /dev/dsp")
    audio_rate = 32e3
    audio_source = audio.source(int(audio_rate), audio_input)