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Compressed audio decoding using PyMedia

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

Example Usage

Playing a MP3 file, known to be 128bkps, 44100Hz 16bit stereo:

Pipeline( RateControlledFileReader("my.mp3", readmode="bytes", rate=128*1024/8),
          Output(44100, 2, "S16_LE"),

How does it work?

Set up Decoder by specifying the filetype/codec to the initializer. What codecs are supported depends on your PyMedia installation.

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

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 Decoder(Axon.Component.component)

Decoder(fileExtension) -> new pymedia Audio Decoder.

Send raw data from a compressed audio file (which had the specified extension) to the "inbox" inbox, and decompressed blocks of raw audio data are emitted from the "outbox" outbox.

Keyword arguments:

  • codec -- The codec (ones supported depend on your local installation)


  • control : Shutdown signalling
  • inbox : compressed audio data


  • outbox : raw audio samples
  • signal : Shutdown signalling
  • needData : requests for more data (value is suggested minimum number of bytes
  • format : dictionary detailing sample_rate, sample_format and channels

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)

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