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(python2.1-lib.info)sunau

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Read and write Sun AU files
===========================

This manual section was written by Moshe Zadka
<moshez@zadka.site.co.il>.
Provide an interface to the Sun AU sound format.

The `sunau' module provides a convenient interface to the Sun AU sound
format.  Note that this module is interface-compatible with the modules
`aifc' and `wave'.

An audio file consists of a header followed by the data.  The fields of
the header are:

Field                                Contents
------                               -----
magic word                           The four bytes `.snd'.
header size                          Size of the header, including info,
                                     in bytes.
data size                            Physical size of the data, in bytes.
encoding                             Indicates how the audio samples are
                                     encoded.
sample rate                          The sampling rate.
# of channels                        The number of channels in the
                                     samples.
info                                 ASCII string giving a description
                                     of the audio file (padded with null
                                     bytes).

Apart from the info field, all header fields are 4 bytes in size.  They
are all 32-bit unsigned integers encoded in big-endian byte order.

The `sunau' module defines the following functions:

`open(file, mode)'
     If FILE is a string, open the file by that name, otherwise treat it
     as a seekable file-like object. MODE can be any of
    ``'r'''
          Read only mode.

    ``'w'''
          Write only mode.

     Note that it does not allow read/write files.

     A MODE of `'r'' returns a `AU_read' object, while a MODE of `'w''
     or `'wb'' returns a `AU_write' object.

`openfp(file, mode)'
     A synonym for `open', maintained for backwards compatibility.

The `sunau' module defines the following exception:

`Error'
     An error raised when something is impossible because of Sun AU
     specs or implementation deficiency.

The `sunau' module defines the following data items:

`AUDIO_FILE_MAGIC'
     An integer every valid Sun AU file begins with, stored in
     big-endian form.  This is the string `.snd' interpreted as an
     integer.

`AUDIO_FILE_ENCODING_MULAW_8'

`AUDIO_FILE_ENCODING_LINEAR_8'

`AUDIO_FILE_ENCODING_LINEAR_16'

`AUDIO_FILE_ENCODING_LINEAR_24'

`AUDIO_FILE_ENCODING_LINEAR_32'

`AUDIO_FILE_ENCODING_ALAW_8'
     Values of the encoding field from the AU header which are
     supported by this module.

`AUDIO_FILE_ENCODING_FLOAT'

`AUDIO_FILE_ENCODING_DOUBLE'

`AUDIO_FILE_ENCODING_ADPCM_G721'

`AUDIO_FILE_ENCODING_ADPCM_G722'

`AUDIO_FILE_ENCODING_ADPCM_G723_3'

`AUDIO_FILE_ENCODING_ADPCM_G723_5'
     Additional known values of the encoding field from the AU header,
     but which are not supported by this module.

AU_read Objects

AU_write Objects