/Doc/library/al.rst
http://unladen-swallow.googlecode.com/ · ReStructuredText · 214 lines · 109 code · 105 blank · 0 comment · 0 complexity · 28c590ceec815b2864ffb194addf14a7 MD5 · raw file
- :mod:`al` --- Audio functions on the SGI
- ========================================
- .. module:: al
- :platform: IRIX
- :synopsis: Audio functions on the SGI.
- :deprecated:
- .. deprecated:: 2.6
- The :mod:`al` module has been deprecated for removal in Python 3.0.
- This module provides access to the audio facilities of the SGI Indy and Indigo
- workstations. See section 3A of the IRIX man pages for details. You'll need to
- read those man pages to understand what these functions do! Some of the
- functions are not available in IRIX releases before 4.0.5. Again, see the
- manual to check whether a specific function is available on your platform.
- All functions and methods defined in this module are equivalent to the C
- functions with ``AL`` prefixed to their name.
- .. index:: module: AL
- Symbolic constants from the C header file ``<audio.h>`` are defined in the
- standard module :mod:`AL`, see below.
- .. warning::
- The current version of the audio library may dump core when bad argument values
- are passed rather than returning an error status. Unfortunately, since the
- precise circumstances under which this may happen are undocumented and hard to
- check, the Python interface can provide no protection against this kind of
- problems. (One example is specifying an excessive queue size --- there is no
- documented upper limit.)
- The module defines the following functions:
- .. function:: openport(name, direction[, config])
- The name and direction arguments are strings. The optional *config* argument is
- a configuration object as returned by :func:`newconfig`. The return value is an
- :dfn:`audio port object`; methods of audio port objects are described below.
- .. function:: newconfig()
- The return value is a new :dfn:`audio configuration object`; methods of audio
- configuration objects are described below.
- .. function:: queryparams(device)
- The device argument is an integer. The return value is a list of integers
- containing the data returned by :cfunc:`ALqueryparams`.
- .. function:: getparams(device, list)
- The *device* argument is an integer. The list argument is a list such as
- returned by :func:`queryparams`; it is modified in place (!).
- .. function:: setparams(device, list)
- The *device* argument is an integer. The *list* argument is a list such as
- returned by :func:`queryparams`.
- .. _al-config-objects:
- Configuration Objects
- ---------------------
- Configuration objects returned by :func:`newconfig` have the following methods:
- .. method:: audio configuration.getqueuesize()
- Return the queue size.
- .. method:: audio configuration.setqueuesize(size)
- Set the queue size.
- .. method:: audio configuration.getwidth()
- Get the sample width.
- .. method:: audio configuration.setwidth(width)
- Set the sample width.
- .. method:: audio configuration.getchannels()
- Get the channel count.
- .. method:: audio configuration.setchannels(nchannels)
- Set the channel count.
- .. method:: audio configuration.getsampfmt()
- Get the sample format.
- .. method:: audio configuration.setsampfmt(sampfmt)
- Set the sample format.
- .. method:: audio configuration.getfloatmax()
- Get the maximum value for floating sample formats.
- .. method:: audio configuration.setfloatmax(floatmax)
- Set the maximum value for floating sample formats.
- .. _al-port-objects:
- Port Objects
- ------------
- Port objects, as returned by :func:`openport`, have the following methods:
- .. method:: audio port.closeport()
- Close the port.
- .. method:: audio port.getfd()
- Return the file descriptor as an int.
- .. method:: audio port.getfilled()
- Return the number of filled samples.
- .. method:: audio port.getfillable()
- Return the number of fillable samples.
- .. method:: audio port.readsamps(nsamples)
- Read a number of samples from the queue, blocking if necessary. Return the data
- as a string containing the raw data, (e.g., 2 bytes per sample in big-endian
- byte order (high byte, low byte) if you have set the sample width to 2 bytes).
- .. method:: audio port.writesamps(samples)
- Write samples into the queue, blocking if necessary. The samples are encoded as
- described for the :meth:`readsamps` return value.
- .. method:: audio port.getfillpoint()
- Return the 'fill point'.
- .. method:: audio port.setfillpoint(fillpoint)
- Set the 'fill point'.
- .. method:: audio port.getconfig()
- Return a configuration object containing the current configuration of the port.
- .. method:: audio port.setconfig(config)
- Set the configuration from the argument, a configuration object.
- .. method:: audio port.getstatus(list)
- Get status information on last error.
- :mod:`AL` --- Constants used with the :mod:`al` module
- ======================================================
- .. module:: AL
- :platform: IRIX
- :synopsis: Constants used with the al module.
- :deprecated:
- .. deprecated:: 2.6
- The :mod:`AL` module has been deprecated for removal in Python 3.0.
- This module defines symbolic constants needed to use the built-in module
- :mod:`al` (see above); they are equivalent to those defined in the C header file
- ``<audio.h>`` except that the name prefix ``AL_`` is omitted. Read the module
- source for a complete list of the defined names. Suggested use::
- import al
- from AL import *