1:mod:`sndhdr` --- Determine type of sound file
2==============================================
3
4.. module:: sndhdr
5   :synopsis: Determine type of a sound file.
6
7.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
8.. Based on comments in the module source file.
9
10**Source code:** :source:`Lib/sndhdr.py`
11
12.. index::
13   single: A-LAW
14   single: u-LAW
15
16--------------
17
18The :mod:`sndhdr` provides utility functions which attempt to determine the type
19of sound data which is in a file.  When these functions are able to determine
20what type of sound data is stored in a file, they return a
21:func:`~collections.namedtuple`, containing five attributes: (``filetype``,
22``framerate``, ``nchannels``, ``nframes``, ``sampwidth``). The value for *type*
23indicates the data type and will be one of the strings ``'aifc'``, ``'aiff'``,
24``'au'``, ``'hcom'``, ``'sndr'``, ``'sndt'``, ``'voc'``, ``'wav'``, ``'8svx'``,
25``'sb'``, ``'ub'``, or ``'ul'``.  The *sampling_rate* will be either the actual
26value or ``0`` if unknown or difficult to decode.  Similarly, *channels* will be
27either the number of channels or ``0`` if it cannot be determined or if the
28value is difficult to decode.  The value for *frames* will be either the number
29of frames or ``-1``.  The last item in the tuple, *bits_per_sample*, will either
30be the sample size in bits or ``'A'`` for A-LAW or ``'U'`` for u-LAW.
31
32
33.. function:: what(filename)
34
35   Determines the type of sound data stored in the file *filename* using
36   :func:`whathdr`.  If it succeeds, returns a namedtuple as described above, otherwise
37   ``None`` is returned.
38
39   .. versionchanged:: 3.5
40      Result changed from a tuple to a namedtuple.
41
42
43.. function:: whathdr(filename)
44
45   Determines the type of sound data stored in a file based on the file  header.
46   The name of the file is given by *filename*.  This function returns a namedtuple as
47   described above on success, or ``None``.
48
49   .. versionchanged:: 3.5
50      Result changed from a tuple to a namedtuple.
51
52