default for each hostapi

Author: dholl

sounddevice.py

@@ -2143,188 +2143,195 @@ def __repr__(self):
         return '[{0[0]!r}, {0[1]!r}]'.format(self)
 
 
-class default(object):
-    """Get/set defaults for the *sounddevice* module.
+def _create_default():
+    class default(object):
+        """Get/set defaults for the *sounddevice* module.
 
-    The attributes `device`, `channels`, `dtype`, `latency` and
-    `extra_settings` accept single values which specify the given
-    property for both input and output.  However, if the property
-    differs between input and output, pairs of values can be used, where
-    the first value specifies the input and the second value specifies
-    the output.  All other attributes are always single values.
+        The attributes `device`, `channels`, `dtype`, `latency` and
+        `extra_settings` accept single values which specify the given
+        property for both input and output.  However, if the property
+        differs between input and output, pairs of values can be used, where
+        the first value specifies the input and the second value specifies
+        the output.  All other attributes are always single values.
 
-    Examples
-    --------
+        Examples
+        --------
 
-    >>> import sounddevice as sd
-    >>> sd.default.samplerate = 48000
-    >>> sd.default.dtype
-    ['float32', 'float32']
+        >>> import sounddevice as sd
+        >>> sd.default.samplerate = 48000
+        >>> sd.default.dtype
+        ['float32', 'float32']
 
-    Different values for input and output:
+        Different values for input and output:
 
-    >>> sd.default.channels = 1, 2
+        >>> sd.default.channels = 1, 2
 
-    A single value sets both input and output at the same time:
+        A single value sets both input and output at the same time:
 
-    >>> sd.default.device = 5
-    >>> sd.default.device
-    [5, 5]
+        >>> sd.default.device = 5
+        >>> sd.default.device
+        [5, 5]
 
-    An attribute can be set to the "factory default" by assigning
-    ``None``:
+        An attribute can be set to the "factory default" by assigning
+        ``None``:
 
-    >>> sd.default.samplerate = None
-    >>> sd.default.device = None, 4
+        >>> sd.default.samplerate = None
+        >>> sd.default.device = None, 4
 
-    Use `reset()` to reset all attributes:
+        Use `reset()` to reset all attributes:
 
-    >>> sd.default.reset()
+        >>> sd.default.reset()
 
-    """
-    _pairs = 'device', 'channels', 'dtype', 'latency', 'extra_settings'
-    # The class attributes listed in _pairs are only provided here for static
-    # analysis tools and for the docs.  They're overwritten in __init__().
-    device = None, None
-    """Index or query string of default input/output device.
+        """
+        _pairs = 'device', 'channels', 'dtype', 'latency', 'extra_settings'
+        # The class attributes listed in _pairs are only provided here for static
+        # analysis tools and for the docs.  They're overwritten in __init__().
+        device = None, None
+        """Index or query string of default input/output device.
 
-    If not overwritten, this is queried from PortAudio.
+        If not overwritten, this is queried from PortAudio.
 
-    If a string is given, the device is selected which contains all
-    space-separated parts in the right order.  Each device string
-    contains the name of the corresponding host API in the end.
-    The string comparison is case-insensitive.
+        If a string is given, the device is selected which contains all
+        space-separated parts in the right order.  Each device string
+        contains the name of the corresponding host API in the end.
+        The string comparison is case-insensitive.
 
-    See Also
-    --------
-    :func:`query_devices`
+        See Also
+        --------
+        :func:`query_devices`
 
-    """
-    channels = _default_channels = None, None
-    """Number of input/output channels.
+        """
+        channels = _default_channels = None, None
+        """Number of input/output channels.
 
-    The maximum number of channels for a given device can be found out
-    with `query_devices()`.
+        The maximum number of channels for a given device can be found out
+        with `query_devices()`.
 
-    """
-    dtype = _default_dtype = 'float32', 'float32'
-    """Data type used for input/output samples.
+        """
+        dtype = _default_dtype = 'float32', 'float32'
+        """Data type used for input/output samples.
 
-    The types ``'float32'``, ``'int32'``, ``'int16'``, ``'int8'`` and
-    ``'uint8'`` can be used for all streams and functions.
-    Additionally, `play()`, `rec()` and `playrec()` support
-    ``'float64'`` (for convenience, data is merely converted from/to
-    ``'float32'``) and `RawInputStream`, `RawOutputStream` and
-    `RawStream` support ``'int24'`` (packed 24 bit format, which is
-    *not* supported in NumPy!).
+        The types ``'float32'``, ``'int32'``, ``'int16'``, ``'int8'`` and
+        ``'uint8'`` can be used for all streams and functions.
+        Additionally, `play()`, `rec()` and `playrec()` support
+        ``'float64'`` (for convenience, data is merely converted from/to
+        ``'float32'``) and `RawInputStream`, `RawOutputStream` and
+        `RawStream` support ``'int24'`` (packed 24 bit format, which is
+        *not* supported in NumPy!).
 
-    If NumPy is available, the corresponding `numpy.dtype` objects can
-    be used as well.
+        If NumPy is available, the corresponding `numpy.dtype` objects can
+        be used as well.
 
-    The floating point representations ``'float32'`` and ``'float64'``
-    use +1.0 and -1.0 as the maximum and minimum values, respectively.
-    ``'uint8'`` is an unsigned 8 bit format where 128 is considered
-    "ground".
+        The floating point representations ``'float32'`` and ``'float64'``
+        use +1.0 and -1.0 as the maximum and minimum values, respectively.
+        ``'uint8'`` is an unsigned 8 bit format where 128 is considered
+        "ground".
 
-    """
-    latency = _default_latency = 'high', 'high'
-    """Suggested input/output latency in seconds.
+        """
+        latency = _default_latency = 'high', 'high'
+        """Suggested input/output latency in seconds.
 
-    The special values ``'low'`` and ``'high'`` can be used to select
-    the default low/high latency of the chosen device.
-    ``'high'`` is typically more robust (i.e. buffer under-/overflows
-    are less likely), but the latency may be too large for interactive
-    applications.
+        The special values ``'low'`` and ``'high'`` can be used to select
+        the default low/high latency of the chosen device.
+        ``'high'`` is typically more robust (i.e. buffer under-/overflows
+        are less likely), but the latency may be too large for interactive
+        applications.
 
-    See Also
-    --------
-    :func:`query_devices`
+        See Also
+        --------
+        :func:`query_devices`
 
-    """
-    extra_settings = _default_extra_settings = None, None
-    """Host-API-specific input/output settings.
+        """
+        extra_settings = _default_extra_settings = None, None
+        """Host-API-specific input/output settings.
 
-    See Also
-    --------
-    AsioSettings, CoreAudioSettings, WasapiSettings
+        See Also
+        --------
+        AsioSettings, CoreAudioSettings, WasapiSettings
 
-    """
-    samplerate = None
-    """Sampling frequency in Hertz (= frames per second).
+        """
+        samplerate = None
+        """Sampling frequency in Hertz (= frames per second).
 
-    See Also
-    --------
-    :func:`query_devices`
+        See Also
+        --------
+        :func:`query_devices`
 
-    """
-    blocksize = _lib.paFramesPerBufferUnspecified
-    """See the *blocksize* argument of `Stream`."""
-    clip_off = False
-    """Disable clipping.
+        """
+        blocksize = _lib.paFramesPerBufferUnspecified
+        """See the *blocksize* argument of `Stream`."""
+        clip_off = False
+        """Disable clipping.
 
-    Set to ``True`` to disable default clipping of out of range samples.
+        Set to ``True`` to disable default clipping of out of range samples.
 
-    """
-    dither_off = False
-    """Disable dithering.
+        """
+        dither_off = False
+        """Disable dithering.
 
-    Set to ``True`` to disable default dithering.
+        Set to ``True`` to disable default dithering.
 
-    """
-    never_drop_input = False
-    """Set behavior for input overflow of full-duplex streams.
-
-    Set to ``True`` to request that where possible a full duplex stream
-    will not discard overflowed input samples without calling the stream
-    callback.  This flag is only valid for full-duplex callback streams
-    (i.e. only `Stream` and `RawStream` and only if *callback* was
-    specified; this includes `playrec()`) and only when used in
-    combination with ``blocksize=0`` (the default).  Using this flag
-    incorrectly results in an error being raised.  See also
-    http://www.portaudio.com/docs/proposals/001-UnderflowOverflowHandling.html.
+        """
+        never_drop_input = False
+        """Set behavior for input overflow of full-duplex streams.
+
+        Set to ``True`` to request that where possible a full duplex stream
+        will not discard overflowed input samples without calling the stream
+        callback.  This flag is only valid for full-duplex callback streams
+        (i.e. only `Stream` and `RawStream` and only if *callback* was
+        specified; this includes `playrec()`) and only when used in
+        combination with ``blocksize=0`` (the default).  Using this flag
+        incorrectly results in an error being raised.  See also
+        http://www.portaudio.com/docs/proposals/001-UnderflowOverflowHandling.html.
 
-    """
-    prime_output_buffers_using_stream_callback = False
-    """How to fill initial output buffers.
+        """
+        prime_output_buffers_using_stream_callback = False
+        """How to fill initial output buffers.
 
-    Set to ``True`` to call the stream callback to fill initial output
-    buffers, rather than the default behavior of priming the buffers
-    with zeros (silence).  This flag has no effect for input-only
-    (`InputStream` and `RawInputStream`) and blocking read/write streams
-    (i.e. if *callback* wasn't specified).  See also
-    http://www.portaudio.com/docs/proposals/020-AllowCallbackToPrimeStream.html.
+        Set to ``True`` to call the stream callback to fill initial output
+        buffers, rather than the default behavior of priming the buffers
+        with zeros (silence).  This flag has no effect for input-only
+        (`InputStream` and `RawInputStream`) and blocking read/write streams
+        (i.e. if *callback* wasn't specified).  See also
+        http://www.portaudio.com/docs/proposals/020-AllowCallbackToPrimeStream.html.
 
-    """
+        """
 
-    def __init__(self):
-        for attr in self._pairs:
-            # __setattr__() must be avoided here
-            vars(self)[attr] = _InputOutputPair(self, '_default_' + attr)
-
-    def __setattr__(self, name, value):
-        """Only allow setting existing attributes."""
-        if name in self._pairs:
-            getattr(self, name)._pair[:] = _split(value)
-        elif name in dir(self) and name != 'reset':
-            object.__setattr__(self, name, value)
-        else:
-            raise AttributeError(
-                "'default' object has no attribute " + repr(name))
+        def __init__(self):
+            for attr in self._pairs:
+                # __setattr__() must be avoided here
+                vars(self)[attr] = _InputOutputPair(self, '_default_' + attr)
+
+        def __setattr__(self, name, value):
+            """Only allow setting existing attributes."""
+            if name in self._pairs:
+                getattr(self, name)._pair[:] = _split(value)
+            elif name in dir(self) and name != 'reset':
+                object.__setattr__(self, name, value)
+            else:
+                raise AttributeError(
+                    "'default' object has no attribute " + repr(name))
 
-    @property
-    def _default_device(self):
-        return (_lib.Pa_GetDefaultInputDevice(),
-                _lib.Pa_GetDefaultOutputDevice())
+        @property
+        def _default_device(self):
+            return (_lib.Pa_GetDefaultInputDevice(),
+                    _lib.Pa_GetDefaultOutputDevice())
 
-    @property
-    def hostapi(self):
-        """Index of the default host API (read-only)."""
-        return _check(_lib.Pa_GetDefaultHostApi())
+        @property
+        def hostapi(self):
+            """Index of the default host API (read-only)."""
+            return _check(_lib.Pa_GetDefaultHostApi())
+
+        def reset(self):
+            """Reset all attributes to their "factory default"."""
+            vars(self).clear()
+            self.__init__()
+
+    return default
+
+
+default = _create_default()
 
-    def reset(self):
-        """Reset all attributes to their "factory default"."""
-        vars(self).clear()
-        self.__init__()
 
 if not hasattr(_ffi, 'I_AM_FAKE'):
     # This object shadows the 'default' class, except when building the docs.
@@ -2450,7 +2457,8 @@ def _populate_hostapis():
     _HostAPI = _namedtuple('_HostAPI', ('name', 'devices',
                                         'default_input_device',
                                         'default_output_device',
-                                        'apiname', 'api'))
+                                        'apiname', 'api', 'default'))
+
     class HostAPIs(_namedtuple('HostAPIs', (h['apiname'] for h in hostapi_list))):
         """Access to PortAudio Host API's"""
         __slots__ = ()
@@ -2460,6 +2468,8 @@ class HostAPIs(_namedtuple('HostAPIs', (h['apiname'] for h in hostapi_list))):
     for apiname in missing_apinames:
         setattr(HostAPIs, apiname, None)
 
+    for hostapi in hostapi_list:
+        hostapi['default'] = _create_default()
     hostapis = HostAPIs(*(_HostAPI(**h) for h in hostapi_list))
 
 
@@ -3092,6 +3102,14 @@ def _check_dtype(dtype):
     return dtype
 
 
+def _get_device_hostapi(device):
+    """Find a device's in hostapis"""
+    for hostapi in hostapis:
+        if device in hostapi.devices:
+            return hostapi
+    return None
+
+
 def _get_stream_parameters(kind, device, channels, dtype, latency,
                            extra_settings, samplerate):
     """Get parameters for one direction (input or output) of a stream."""
@@ -3110,6 +3128,19 @@ def _get_stream_parameters(kind, device, channels, dtype, latency,
         samplerate = default.samplerate
 
     device = _get_device_id(device, kind, raise_on_error=True)
+    hostapi = _get_device_hostapi(device)
+    if hostapi:
+        if channels is None:
+            channels = hostapi.default.channels[kind]
+        if dtype is None:
+            dtype = hostapi.default.dtype[kind]
+        if latency is None:
+            latency = hostapi.default.latency[kind]
+        if extra_settings is None:
+            extra_settings = hostapi.default.extra_settings[kind]
+        if samplerate is None:
+            samplerate = hostapi.default.samplerate
+
     info = query_devices(device)
     if channels is None:
         channels = info['max_' + kind + '_channels']