symbian-qemu-0.9.1-12/python-2.6.1/Doc/library/sndhdr.rst
author johnathan.white@2718R8BGH51.accenture.com
Mon, 08 Mar 2010 18:45:03 +0000
changeset 46 b6935a90ca64
parent 1 2fb8b9db1c86
permissions -rw-r--r--
Modify framebuffer and NGA framebuffer to read screen size from board model dtb file. Optimise memory usuage of frame buffer Add example minigui application with hooks to profiler (which writes results to S:\). Modified NGA framebuffer to run its own dfc queue at high priority


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

.. module:: sndhdr
   :synopsis: Determine type of a sound file.
.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
.. Based on comments in the module source file.

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

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 tuple ``(type,
sampling_rate, channels, frames, bits_per_sample)``.  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 tuple as described above, otherwise
   ``None`` is returned.


.. 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 tuple as
   described above on success, or ``None``.