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Audio encoding using PyMedia

Encodes raw audio data sent to its "inbox" inbox and outputs the compressed audio data from its "outbox" outbox. Decoding done using the PyMedia library.

Example Usage

Capturing to an MP3 file:

Pipeline( Input(44100, 2, "S16_LE"),
          Encoder("mp3", bitrate=128000, sample_rate=44100, channels=2)

How does it work?

Set up Encoder by specifying the desired compression codec and bitrate and the sample rate and number of channels of the raw audio. You may also specify other parameters specific to pymedia and the particular codec.

Send raw binary data strings containing the raw audio data to the "inbox" inbox, and raw binary data strings containing the compressed audio data will be sent out of the "outbox" outbox.

Encoder only supports a sample format of "S16_LE".

This component will terminate if a shutdownMicroprocess or producerFinished message is sent to the "control" inbox. The message will be forwarded on out of the "signal" outbox just before termination.


class Encoder(Axon.Component.component)

Encoder(codec,bitrate,sample_rate,channels,**otherparams) -> new Encoder component.

Send raw audio data to the "inbox" inbox, and compressed audio data will be sent out of the "outbox" outbox.

Keyword arguments:

  • codec -- which codec to use, eg "MP3"
  • bitrate -- desired bitrate, eg 128000 for 128kbps
  • sample_rate -- sample rate in Hz of the raw audio
  • channels -- number of channels of the raw audio
  • otherparams -- any other keyword arguments to be passed direct to PyMedia


  • control : Shutdown signalling
  • inbox : Raw binary audio data as strings


  • outbox : NOT USED
  • signal : Shutdown signalling

Methods defined here


You should be using the inbox/outbox interface, not these methods (except construction). This documentation is designed as a roadmap as to their functionalilty for maintainers and new component developers.

__init__(self, codec, bitrate, sample_rate, channels, **otherparams)

x.__init__(...) initializes x; see x.__class__.__doc__ for signature



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-- Automatic documentation generator, 05 Jun 2009 at 03:01:38 UTC/GMT