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:mod:`sndhdr` --- Determine type of sound file

.. module:: sndhdr
   :synopsis: Determine type of a sound file.
   :deprecated:


.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>

Source code: :source:`Lib/sndhdr.py`

.. index::
   single: A-LAW
   single: u-LAW


.. deprecated-removed:: 3.11 3.13
   The :mod:`sndhdr` module is deprecated
   (see :pep:`PEP 594 <594#sndhdr>` for details and alternatives).

The :mod:`sndhdr` provides utility functions which attempt to determine the type of sound data which is in a file. When these functions are able to determine what type of sound data is stored in a file, they return a :func:`~collections.namedtuple`, containing five attributes: (filetype, framerate, nchannels, nframes, sampwidth). The value for type indicates the data type and will be one of the strings 'aifc', 'aiff', 'au', 'hcom', 'sndr', 'sndt', 'voc', 'wav', '8svx', 'sb', 'ub', or 'ul'. The sampling_rate will be either the actual value or 0 if unknown or difficult to decode. Similarly, channels will be either the number of channels or 0 if it cannot be determined or if the value is difficult to decode. The value for frames will be either the number of frames or -1. The last item in the tuple, bits_per_sample, will either be the sample size in bits or 'A' for A-LAW or 'U' for u-LAW.

.. function:: what(filename)

   Determines the type of sound data stored in the file *filename* using
   :func:`whathdr`.  If it succeeds, returns a namedtuple as described above, otherwise
   ``None`` is returned.

   .. versionchanged:: 3.5
      Result changed from a tuple to a namedtuple.



.. function:: whathdr(filename)

   Determines the type of sound data stored in a file based on the file  header.
   The name of the file is given by *filename*.  This function returns a namedtuple as
   described above on success, or ``None``.

   .. versionchanged:: 3.5
      Result changed from a tuple to a namedtuple.

The following sound header types are recognized, as listed below with the return value from :func:`whathdr`: and :func:`what`:

Value Sound header format
'aifc' Compressed Audio Interchange Files
'aiff' Audio Interchange Files
'au' Au Files
'hcom' HCOM Files
'sndt' Sndtool Sound Files
'voc' Creative Labs Audio Files
'wav' Waveform Audio File Format Files
'8svx' 8-Bit Sampled Voice Files
'sb' Signed Byte Audio Data Files
'ub' UB Files
'ul' uLAW Audio Files 
.. data:: tests

   A list of functions performing the individual tests.  Each function takes two
   arguments: the byte-stream and an open file-like object. When :func:`what` is
   called with a byte-stream, the file-like object will be ``None``.

   The test function should return a string describing the image type if the test
   succeeded, or ``None`` if it failed.

Example:

>>> import sndhdr
>>> imghdr.what('bass.wav')
'wav'
>>> imghdr.whathdr('bass.wav')
'wav'