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// NOTE: Copy this file to portaudio.h in order to compile with V19 portaudio
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#ifndef PORTAUDIO_H
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#define PORTAUDIO_H
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/*
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* $Id: portaudio.h 1061 2006-06-19 22:46:41Z lschwardt $
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* PortAudio Portable Real-Time Audio Library
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* PortAudio API Header File
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* Latest version available at: http://www.portaudio.com/
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*
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* Copyright (c) 1999-2002 Ross Bencina and Phil Burk
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*
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* Permission is hereby granted, free of charge, to any person obtaining
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* a copy of this software and associated documentation files
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* (the "Software"), to deal in the Software without restriction,
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* including without limitation the rights to use, copy, modify, merge,
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* publish, distribute, sublicense, and/or sell copies of the Software,
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* and to permit persons to whom the Software is furnished to do so,
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* subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be
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* included in all copies or substantial portions of the Software.
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*
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* Any person wishing to distribute modifications to the Software is
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* requested to send the modifications to the original developer so that
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* they can be incorporated into the canonical version.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
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* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
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* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
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* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
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* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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*/
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/** @file
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@brief The PortAudio API.
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*/
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#ifdef __cplusplus
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extern "C"
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{
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#endif /* __cplusplus */
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/** Retrieve the release number of the currently running PortAudio build,
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eg 1900.
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*/
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int Pa_GetVersion( void );
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/** Retrieve a textual description of the current PortAudio build,
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eg "PortAudio V19-devel 13 October 2002".
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*/
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const char* Pa_GetVersionText( void );
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/** Error codes returned by PortAudio functions.
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Note that with the exception of paNoError, all PaErrorCodes are negative.
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*/
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typedef int PaError;
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typedef enum PaErrorCode
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{
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paNoError = 0,
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paNotInitialized = -10000,
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paUnanticipatedHostError,
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paInvalidChannelCount,
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paInvalidSampleRate,
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paInvalidDevice,
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paInvalidFlag,
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paSampleFormatNotSupported,
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paBadIODeviceCombination,
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paInsufficientMemory,
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paBufferTooBig,
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paBufferTooSmall,
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paNullCallback,
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paBadStreamPtr,
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paTimedOut,
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paInternalError,
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paDeviceUnavailable,
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paIncompatibleHostApiSpecificStreamInfo,
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paStreamIsStopped,
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paStreamIsNotStopped,
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paInputOverflowed,
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paOutputUnderflowed,
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paHostApiNotFound,
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paInvalidHostApi,
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paCanNotReadFromACallbackStream, /**< @todo review error code name */
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paCanNotWriteToACallbackStream, /**< @todo review error code name */
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paCanNotReadFromAnOutputOnlyStream, /**< @todo review error code name */
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paCanNotWriteToAnInputOnlyStream, /**< @todo review error code name */
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paIncompatibleStreamHostApi,
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paBadBufferPtr
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} PaErrorCode;
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/** Translate the supplied PortAudio error code into a human readable
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message.
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*/
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const char *Pa_GetErrorText( PaError errorCode );
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/** Library initialization function - call this before using PortAudio.
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This function initialises internal data structures and prepares underlying
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host APIs for use. This function MUST be called before using any other
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PortAudio API functions.
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If Pa_Initialize() is called multiple times, each successful
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call must be matched with a corresponding call to Pa_Terminate().
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Pairs of calls to Pa_Initialize()/Pa_Terminate() may overlap, and are not
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required to be fully nested.
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Note that if Pa_Initialize() returns an error code, Pa_Terminate() should
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NOT be called.
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@return paNoError if successful, otherwise an error code indicating the cause
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of failure.
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@see Pa_Terminate
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*/
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PaError Pa_Initialize( void );
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/** Library termination function - call this when finished using PortAudio.
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This function deallocates all resources allocated by PortAudio since it was
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initializied by a call to Pa_Initialize(). In cases where Pa_Initialise() has
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been called multiple times, each call must be matched with a corresponding call
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to Pa_Terminate(). The final matching call to Pa_Terminate() will automatically
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close any PortAudio streams that are still open.
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Pa_Terminate() MUST be called before exiting a program which uses PortAudio.
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Failure to do so may result in serious resource leaks, such as audio devices
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not being available until the next reboot.
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@return paNoError if successful, otherwise an error code indicating the cause
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of failure.
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@see Pa_Initialize
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*/
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PaError Pa_Terminate( void );
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/** The type used to refer to audio devices. Values of this type usually
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range from 0 to (Pa_DeviceCount-1), and may also take on the PaNoDevice
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and paUseHostApiSpecificDeviceSpecification values.
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@see Pa_DeviceCount, paNoDevice, paUseHostApiSpecificDeviceSpecification
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*/
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typedef int PaDeviceIndex;
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/** A special PaDeviceIndex value indicating that no device is available,
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or should be used.
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@see PaDeviceIndex
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*/
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#define paNoDevice ((PaDeviceIndex)-1)
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/** A special PaDeviceIndex value indicating that the device(s) to be used
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are specified in the host api specific stream info structure.
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@see PaDeviceIndex
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*/
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#define paUseHostApiSpecificDeviceSpecification ((PaDeviceIndex)-2)
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/* Host API enumeration mechanism */
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/** The type used to enumerate to host APIs at runtime. Values of this type
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range from 0 to (Pa_GetHostApiCount()-1).
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@see Pa_GetHostApiCount
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*/
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typedef int PaHostApiIndex;
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/** Retrieve the number of available host APIs. Even if a host API is
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available it may have no devices available.
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@return A non-negative value indicating the number of available host APIs
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or, a PaErrorCode (which are always negative) if PortAudio is not initialized
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or an error is encountered.
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@see PaHostApiIndex
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*/
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PaHostApiIndex Pa_GetHostApiCount( void );
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/** Retrieve the index of the default host API. The default host API will be
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the lowest common denominator host API on the current platform and is
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unlikely to provide the best performance.
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@return A non-negative value ranging from 0 to (Pa_GetHostApiCount()-1)
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indicating the default host API index or, a PaErrorCode (which are always
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negative) if PortAudio is not initialized or an error is encountered.
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*/
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PaHostApiIndex Pa_GetDefaultHostApi( void );
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/** Unchanging unique identifiers for each supported host API. This type
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is used in the PaHostApiInfo structure. The values are guaranteed to be
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unique and to never change, thus allowing code to be written that
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conditionally uses host API specific extensions.
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New type ids will be allocated when support for a host API reaches
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"public alpha" status, prior to that developers should use the
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paInDevelopment type id.
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@see PaHostApiInfo
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*/
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typedef enum PaHostApiTypeId
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{
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paInDevelopment=0, /* use while developing support for a new host API */
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paDirectSound=1,
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paMME=2,
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paASIO=3,
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paSoundManager=4,
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paCoreAudio=5,
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paOSS=7,
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paALSA=8,
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paAL=9,
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paBeOS=10,
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paWDMKS=11,
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paJACK=12,
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paWASAPI=13,
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paAudioScienceHPI=14
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} PaHostApiTypeId;
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/** A structure containing information about a particular host API. */
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typedef struct PaHostApiInfo
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{
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/** this is struct version 1 */
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int structVersion;
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/** The well known unique identifier of this host API @see PaHostApiTypeId */
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PaHostApiTypeId type;
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/** A textual description of the host API for display on user interfaces. */
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const char *name;
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/** The number of devices belonging to this host API. This field may be
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used in conjunction with Pa_HostApiDeviceIndexToDeviceIndex() to enumerate
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all devices for this host API.
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@see Pa_HostApiDeviceIndexToDeviceIndex
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*/
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int deviceCount;
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/** The default input device for this host API. The value will be a
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device index ranging from 0 to (Pa_GetDeviceCount()-1), or paNoDevice
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if no default input device is available.
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*/
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PaDeviceIndex defaultInputDevice;
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/** The default output device for this host API. The value will be a
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device index ranging from 0 to (Pa_GetDeviceCount()-1), or paNoDevice
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if no default output device is available.
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*/
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PaDeviceIndex defaultOutputDevice;
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} PaHostApiInfo;
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/** Retrieve a pointer to a structure containing information about a specific
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host Api.
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@param hostApi A valid host API index ranging from 0 to (Pa_GetHostApiCount()-1)
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@return A pointer to an immutable PaHostApiInfo structure describing
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a specific host API. If the hostApi parameter is out of range or an error
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is encountered, the function returns NULL.
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The returned structure is owned by the PortAudio implementation and must not
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be manipulated or freed. The pointer is only guaranteed to be valid between
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calls to Pa_Initialize() and Pa_Terminate().
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*/
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const PaHostApiInfo * Pa_GetHostApiInfo( PaHostApiIndex hostApi );
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/** Convert a static host API unique identifier, into a runtime
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host API index.
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@param type A unique host API identifier belonging to the PaHostApiTypeId
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enumeration.
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@return A valid PaHostApiIndex ranging from 0 to (Pa_GetHostApiCount()-1) or,
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a PaErrorCode (which are always negative) if PortAudio is not initialized
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or an error is encountered.
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The paHostApiNotFound error code indicates that the host API specified by the
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type parameter is not available.
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|
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@see PaHostApiTypeId
|
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*/
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PaHostApiIndex Pa_HostApiTypeIdToHostApiIndex( PaHostApiTypeId type );
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|
302 |
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/** Convert a host-API-specific device index to standard PortAudio device index.
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This function may be used in conjunction with the deviceCount field of
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PaHostApiInfo to enumerate all devices for the specified host API.
|
306 |
|
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@param hostApi A valid host API index ranging from 0 to (Pa_GetHostApiCount()-1)
|
308 |
|
309 |
@param hostApiDeviceIndex A valid per-host device index in the range
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0 to (Pa_GetHostApiInfo(hostApi)->deviceCount-1)
|
311 |
|
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@return A non-negative PaDeviceIndex ranging from 0 to (Pa_GetDeviceCount()-1)
|
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or, a PaErrorCode (which are always negative) if PortAudio is not initialized
|
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or an error is encountered.
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315 |
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A paInvalidHostApi error code indicates that the host API index specified by
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317 |
the hostApi parameter is out of range.
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318 |
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A paInvalidDevice error code indicates that the hostApiDeviceIndex parameter
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is out of range.
|
321 |
|
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@see PaHostApiInfo
|
323 |
*/
|
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PaDeviceIndex Pa_HostApiDeviceIndexToDeviceIndex( PaHostApiIndex hostApi,
|
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int hostApiDeviceIndex );
|
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|
327 |
|
328 |
|
329 |
/** Structure used to return information about a host error condition.
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*/
|
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typedef struct PaHostErrorInfo{
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PaHostApiTypeId hostApiType; /**< the host API which returned the error code */
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long errorCode; /**< the error code returned */
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const char *errorText; /**< a textual description of the error if available, otherwise a zero-length string */
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}PaHostErrorInfo;
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|
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|
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/** Return information about the last host error encountered. The error
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339 |
information returned by Pa_GetLastHostErrorInfo() will never be modified
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asyncronously by errors occurring in other PortAudio owned threads
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(such as the thread that manages the stream callback.)
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This function is provided as a last resort, primarily to enhance debugging
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by providing clients with access to all available error information.
|
345 |
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@return A pointer to an immutable structure constaining information about
|
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the host error. The values in this structure will only be valid if a
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PortAudio function has previously returned the paUnanticipatedHostError
|
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error code.
|
350 |
*/
|
351 |
const PaHostErrorInfo* Pa_GetLastHostErrorInfo( void );
|
352 |
|
353 |
|
354 |
|
355 |
/* Device enumeration and capabilities */
|
356 |
|
357 |
/** Retrieve the number of available devices. The number of available devices
|
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may be zero.
|
359 |
|
360 |
@return A non-negative value indicating the number of available devices or,
|
361 |
a PaErrorCode (which are always negative) if PortAudio is not initialized
|
362 |
or an error is encountered.
|
363 |
*/
|
364 |
PaDeviceIndex Pa_GetDeviceCount( void );
|
365 |
|
366 |
|
367 |
/** Retrieve the index of the default input device. The result can be
|
368 |
used in the inputDevice parameter to Pa_OpenStream().
|
369 |
|
370 |
@return The default input device index for the default host API, or paNoDevice
|
371 |
if no default input device is available or an error was encountered.
|
372 |
*/
|
373 |
PaDeviceIndex Pa_GetDefaultInputDevice( void );
|
374 |
|
375 |
|
376 |
/** Retrieve the index of the default output device. The result can be
|
377 |
used in the outputDevice parameter to Pa_OpenStream().
|
378 |
|
379 |
@return The default output device index for the defualt host API, or paNoDevice
|
380 |
if no default output device is available or an error was encountered.
|
381 |
|
382 |
@note
|
383 |
On the PC, the user can specify a default device by
|
384 |
setting an environment variable. For example, to use device #1.
|
385 |
<pre>
|
386 |
set PA_RECOMMENDED_OUTPUT_DEVICE=1
|
387 |
</pre>
|
388 |
The user should first determine the available device ids by using
|
389 |
the supplied application "pa_devs".
|
390 |
*/
|
391 |
PaDeviceIndex Pa_GetDefaultOutputDevice( void );
|
392 |
|
393 |
|
394 |
/** The type used to represent monotonic time in seconds that can be used
|
395 |
for syncronisation. The type is used for the outTime argument to the
|
396 |
PaStreamCallback and as the result of Pa_GetStreamTime().
|
397 |
|
398 |
@see PaStreamCallback, Pa_GetStreamTime
|
399 |
*/
|
400 |
typedef double PaTime;
|
401 |
|
402 |
|
403 |
/** A type used to specify one or more sample formats. Each value indicates
|
404 |
a possible format for sound data passed to and from the stream callback,
|
405 |
Pa_ReadStream and Pa_WriteStream.
|
406 |
|
407 |
The standard formats paFloat32, paInt16, paInt32, paInt24, paInt8
|
408 |
and aUInt8 are usually implemented by all implementations.
|
409 |
|
410 |
The floating point representation (paFloat32) uses +1.0 and -1.0 as the
|
411 |
maximum and minimum respectively.
|
412 |
|
413 |
paUInt8 is an unsigned 8 bit format where 128 is considered "ground"
|
414 |
|
415 |
The paNonInterleaved flag indicates that a multichannel buffer is passed
|
416 |
as a set of non-interleaved pointers.
|
417 |
|
418 |
@see Pa_OpenStream, Pa_OpenDefaultStream, PaDeviceInfo
|
419 |
@see paFloat32, paInt16, paInt32, paInt24, paInt8
|
420 |
@see paUInt8, paCustomFormat, paNonInterleaved
|
421 |
*/
|
422 |
typedef unsigned long PaSampleFormat;
|
423 |
|
424 |
|
425 |
#define paFloat32 ((PaSampleFormat) 0x00000001) /**< @see PaSampleFormat */
|
426 |
#define paInt32 ((PaSampleFormat) 0x00000002) /**< @see PaSampleFormat */
|
427 |
#define paInt24 ((PaSampleFormat) 0x00000004) /**< Packed 24 bit format. @see PaSampleFormat */
|
428 |
#define paInt16 ((PaSampleFormat) 0x00000008) /**< @see PaSampleFormat */
|
429 |
#define paInt8 ((PaSampleFormat) 0x00000010) /**< @see PaSampleFormat */
|
430 |
#define paUInt8 ((PaSampleFormat) 0x00000020) /**< @see PaSampleFormat */
|
431 |
#define paCustomFormat ((PaSampleFormat) 0x00010000)/**< @see PaSampleFormat */
|
432 |
|
433 |
#define paNonInterleaved ((PaSampleFormat) 0x80000000)
|
434 |
|
435 |
/** A structure providing information and capabilities of PortAudio devices.
|
436 |
Devices may support input, output or both input and output.
|
437 |
*/
|
438 |
typedef struct PaDeviceInfo
|
439 |
{
|
440 |
int structVersion; /* this is struct version 2 */
|
441 |
const char *name;
|
442 |
PaHostApiIndex hostApi; /* note this is a host API index, not a type id*/
|
443 |
|
444 |
int maxInputChannels;
|
445 |
int maxOutputChannels;
|
446 |
|
447 |
/* Default latency values for interactive performance. */
|
448 |
PaTime defaultLowInputLatency;
|
449 |
PaTime defaultLowOutputLatency;
|
450 |
/* Default latency values for robust non-interactive applications (eg. playing sound files). */
|
451 |
PaTime defaultHighInputLatency;
|
452 |
PaTime defaultHighOutputLatency;
|
453 |
|
454 |
double defaultSampleRate;
|
455 |
} PaDeviceInfo;
|
456 |
|
457 |
|
458 |
/** Retrieve a pointer to a PaDeviceInfo structure containing information
|
459 |
about the specified device.
|
460 |
@return A pointer to an immutable PaDeviceInfo structure. If the device
|
461 |
parameter is out of range the function returns NULL.
|
462 |
|
463 |
@param device A valid device index in the range 0 to (Pa_GetDeviceCount()-1)
|
464 |
|
465 |
@note PortAudio manages the memory referenced by the returned pointer,
|
466 |
the client must not manipulate or free the memory. The pointer is only
|
467 |
guaranteed to be valid between calls to Pa_Initialize() and Pa_Terminate().
|
468 |
|
469 |
@see PaDeviceInfo, PaDeviceIndex
|
470 |
*/
|
471 |
const PaDeviceInfo* Pa_GetDeviceInfo( PaDeviceIndex device );
|
472 |
|
473 |
|
474 |
/** Parameters for one direction (input or output) of a stream.
|
475 |
*/
|
476 |
typedef struct PaStreamParameters
|
477 |
{
|
478 |
/** A valid device index in the range 0 to (Pa_GetDeviceCount()-1)
|
479 |
specifying the device to be used or the special constant
|
480 |
paUseHostApiSpecificDeviceSpecification which indicates that the actual
|
481 |
device(s) to use are specified in hostApiSpecificStreamInfo.
|
482 |
This field must not be set to paNoDevice.
|
483 |
*/
|
484 |
PaDeviceIndex device;
|
485 |
|
486 |
/** The number of channels of sound to be delivered to the
|
487 |
stream callback or accessed by Pa_ReadStream() or Pa_WriteStream().
|
488 |
It can range from 1 to the value of maxInputChannels in the
|
489 |
PaDeviceInfo record for the device specified by the device parameter.
|
490 |
*/
|
491 |
int channelCount;
|
492 |
|
493 |
/** The sample format of the buffer provided to the stream callback,
|
494 |
a_ReadStream() or Pa_WriteStream(). It may be any of the formats described
|
495 |
by the PaSampleFormat enumeration.
|
496 |
*/
|
497 |
PaSampleFormat sampleFormat;
|
498 |
|
499 |
/** The desired latency in seconds. Where practical, implementations should
|
500 |
configure their latency based on these parameters, otherwise they may
|
501 |
choose the closest viable latency instead. Unless the suggested latency
|
502 |
is greater than the absolute upper limit for the device implementations
|
503 |
should round the suggestedLatency up to the next practial value - ie to
|
504 |
provide an equal or higher latency than suggestedLatency wherever possibe.
|
505 |
Actual latency values for an open stream may be retrieved using the
|
506 |
inputLatency and outputLatency fields of the PaStreamInfo structure
|
507 |
returned by Pa_GetStreamInfo().
|
508 |
@see default*Latency in PaDeviceInfo, *Latency in PaStreamInfo
|
509 |
*/
|
510 |
PaTime suggestedLatency;
|
511 |
|
512 |
/** An optional pointer to a host api specific data structure
|
513 |
containing additional information for device setup and/or stream processing.
|
514 |
hostApiSpecificStreamInfo is never required for correct operation,
|
515 |
if not used it should be set to NULL.
|
516 |
*/
|
517 |
void *hostApiSpecificStreamInfo;
|
518 |
|
519 |
} PaStreamParameters;
|
520 |
|
521 |
|
522 |
/** Return code for Pa_IsFormatSupported indicating success. */
|
523 |
#define paFormatIsSupported (0)
|
524 |
|
525 |
/** Determine whether it would be possible to open a stream with the specified
|
526 |
parameters.
|
527 |
|
528 |
@param inputParameters A structure that describes the input parameters used to
|
529 |
open a stream. The suggestedLatency field is ignored. See PaStreamParameters
|
530 |
for a description of these parameters. inputParameters must be NULL for
|
531 |
output-only streams.
|
532 |
|
533 |
@param outputParameters A structure that describes the output parameters used
|
534 |
to open a stream. The suggestedLatency field is ignored. See PaStreamParameters
|
535 |
for a description of these parameters. outputParameters must be NULL for
|
536 |
input-only streams.
|
537 |
|
538 |
@param sampleRate The required sampleRate. For full-duplex streams it is the
|
539 |
sample rate for both input and output
|
540 |
|
541 |
@return Returns 0 if the format is supported, and an error code indicating why
|
542 |
the format is not supported otherwise. The constant paFormatIsSupported is
|
543 |
provided to compare with the return value for success.
|
544 |
|
545 |
@see paFormatIsSupported, PaStreamParameters
|
546 |
*/
|
547 |
PaError Pa_IsFormatSupported( const PaStreamParameters *inputParameters,
|
548 |
const PaStreamParameters *outputParameters,
|
549 |
double sampleRate );
|
550 |
|
551 |
|
552 |
|
553 |
/* Streaming types and functions */
|
554 |
|
555 |
|
556 |
/**
|
557 |
A single PaStream can provide multiple channels of real-time
|
558 |
streaming audio input and output to a client application. A stream
|
559 |
provides access to audio hardware represented by one or more
|
560 |
PaDevices. Depending on the underlying Host API, it may be possible
|
561 |
to open multiple streams using the same device, however this behavior
|
562 |
is implementation defined. Portable applications should assume that
|
563 |
a PaDevice may be simultaneously used by at most one PaStream.
|
564 |
|
565 |
Pointers to PaStream objects are passed between PortAudio functions that
|
566 |
operate on streams.
|
567 |
|
568 |
@see Pa_OpenStream, Pa_OpenDefaultStream, Pa_OpenDefaultStream, Pa_CloseStream,
|
569 |
Pa_StartStream, Pa_StopStream, Pa_AbortStream, Pa_IsStreamActive,
|
570 |
Pa_GetStreamTime, Pa_GetStreamCpuLoad
|
571 |
|
572 |
*/
|
573 |
typedef void PaStream;
|
574 |
|
575 |
|
576 |
/** Can be passed as the framesPerBuffer parameter to Pa_OpenStream()
|
577 |
or Pa_OpenDefaultStream() to indicate that the stream callback will
|
578 |
accept buffers of any size.
|
579 |
*/
|
580 |
#define paFramesPerBufferUnspecified (0)
|
581 |
|
582 |
|
583 |
/** Flags used to control the behavior of a stream. They are passed as
|
584 |
parameters to Pa_OpenStream or Pa_OpenDefaultStream. Multiple flags may be
|
585 |
ORed together.
|
586 |
|
587 |
@see Pa_OpenStream, Pa_OpenDefaultStream
|
588 |
@see paNoFlag, paClipOff, paDitherOff, paNeverDropInput,
|
589 |
paPrimeOutputBuffersUsingStreamCallback, paPlatformSpecificFlags
|
590 |
*/
|
591 |
typedef unsigned long PaStreamFlags;
|
592 |
|
593 |
/** @see PaStreamFlags */
|
594 |
#define paNoFlag ((PaStreamFlags) 0)
|
595 |
|
596 |
/** Disable default clipping of out of range samples.
|
597 |
@see PaStreamFlags
|
598 |
*/
|
599 |
#define paClipOff ((PaStreamFlags) 0x00000001)
|
600 |
|
601 |
/** Disable default dithering.
|
602 |
@see PaStreamFlags
|
603 |
*/
|
604 |
#define paDitherOff ((PaStreamFlags) 0x00000002)
|
605 |
|
606 |
/** Flag requests that where possible a full duplex stream will not discard
|
607 |
overflowed input samples without calling the stream callback. This flag is
|
608 |
only valid for full duplex callback streams and only when used in combination
|
609 |
with the paFramesPerBufferUnspecified (0) framesPerBuffer parameter. Using
|
610 |
this flag incorrectly results in a paInvalidFlag error being returned from
|
611 |
Pa_OpenStream and Pa_OpenDefaultStream.
|
612 |
|
613 |
@see PaStreamFlags, paFramesPerBufferUnspecified
|
614 |
*/
|
615 |
#define paNeverDropInput ((PaStreamFlags) 0x00000004)
|
616 |
|
617 |
/** Call the stream callback to fill initial output buffers, rather than the
|
618 |
default behavior of priming the buffers with zeros (silence). This flag has
|
619 |
no effect for input-only and blocking read/write streams.
|
620 |
|
621 |
@see PaStreamFlags
|
622 |
*/
|
623 |
#define paPrimeOutputBuffersUsingStreamCallback ((PaStreamFlags) 0x00000008)
|
624 |
|
625 |
/** A mask specifying the platform specific bits.
|
626 |
@see PaStreamFlags
|
627 |
*/
|
628 |
#define paPlatformSpecificFlags ((PaStreamFlags)0xFFFF0000)
|
629 |
|
630 |
/**
|
631 |
Timing information for the buffers passed to the stream callback.
|
632 |
*/
|
633 |
typedef struct PaStreamCallbackTimeInfo{
|
634 |
PaTime inputBufferAdcTime;
|
635 |
PaTime currentTime;
|
636 |
PaTime outputBufferDacTime;
|
637 |
} PaStreamCallbackTimeInfo;
|
638 |
|
639 |
|
640 |
/**
|
641 |
Flag bit constants for the statusFlags to PaStreamCallback.
|
642 |
|
643 |
@see paInputUnderflow, paInputOverflow, paOutputUnderflow, paOutputOverflow,
|
644 |
paPrimingOutput
|
645 |
*/
|
646 |
typedef unsigned long PaStreamCallbackFlags;
|
647 |
|
648 |
/** In a stream opened with paFramesPerBufferUnspecified, indicates that
|
649 |
input data is all silence (zeros) because no real data is available. In a
|
650 |
stream opened without paFramesPerBufferUnspecified, it indicates that one or
|
651 |
more zero samples have been inserted into the input buffer to compensate
|
652 |
for an input underflow.
|
653 |
@see PaStreamCallbackFlags
|
654 |
*/
|
655 |
#define paInputUnderflow ((PaStreamCallbackFlags) 0x00000001)
|
656 |
|
657 |
/** In a stream opened with paFramesPerBufferUnspecified, indicates that data
|
658 |
prior to the first sample of the input buffer was discarded due to an
|
659 |
overflow, possibly because the stream callback is using too much CPU time.
|
660 |
Otherwise indicates that data prior to one or more samples in the
|
661 |
input buffer was discarded.
|
662 |
@see PaStreamCallbackFlags
|
663 |
*/
|
664 |
#define paInputOverflow ((PaStreamCallbackFlags) 0x00000002)
|
665 |
|
666 |
/** Indicates that output data (or a gap) was inserted, possibly because the
|
667 |
stream callback is using too much CPU time.
|
668 |
@see PaStreamCallbackFlags
|
669 |
*/
|
670 |
#define paOutputUnderflow ((PaStreamCallbackFlags) 0x00000004)
|
671 |
|
672 |
/** Indicates that output data will be discarded because no room is available.
|
673 |
@see PaStreamCallbackFlags
|
674 |
*/
|
675 |
#define paOutputOverflow ((PaStreamCallbackFlags) 0x00000008)
|
676 |
|
677 |
/** Some of all of the output data will be used to prime the stream, input
|
678 |
data may be zero.
|
679 |
@see PaStreamCallbackFlags
|
680 |
*/
|
681 |
#define paPrimingOutput ((PaStreamCallbackFlags) 0x00000010)
|
682 |
|
683 |
/**
|
684 |
Allowable return values for the PaStreamCallback.
|
685 |
@see PaStreamCallback
|
686 |
*/
|
687 |
typedef enum PaStreamCallbackResult
|
688 |
{
|
689 |
paContinue=0,
|
690 |
paComplete=1,
|
691 |
paAbort=2
|
692 |
} PaStreamCallbackResult;
|
693 |
|
694 |
|
695 |
/**
|
696 |
Functions of type PaStreamCallback are implemented by PortAudio clients.
|
697 |
They consume, process or generate audio in response to requests from an
|
698 |
active PortAudio stream.
|
699 |
|
700 |
@param input and @param output are arrays of interleaved samples,
|
701 |
the format, packing and number of channels used by the buffers are
|
702 |
determined by parameters to Pa_OpenStream().
|
703 |
|
704 |
@param frameCount The number of sample frames to be processed by
|
705 |
the stream callback.
|
706 |
|
707 |
@param timeInfo The time in seconds when the first sample of the input
|
708 |
buffer was received at the audio input, the time in seconds when the first
|
709 |
sample of the output buffer will begin being played at the audio output, and
|
710 |
the time in seconds when the stream callback was called.
|
711 |
See also Pa_GetStreamTime()
|
712 |
|
713 |
@param statusFlags Flags indicating whether input and/or output buffers
|
714 |
have been inserted or will be dropped to overcome underflow or overflow
|
715 |
conditions.
|
716 |
|
717 |
@param userData The value of a user supplied pointer passed to
|
718 |
Pa_OpenStream() intended for storing synthesis data etc.
|
719 |
|
720 |
@return
|
721 |
The stream callback should return one of the values in the
|
722 |
PaStreamCallbackResult enumeration. To ensure that the callback continues
|
723 |
to be called, it should return paContinue (0). Either paComplete or paAbort
|
724 |
can be returned to finish stream processing, after either of these values is
|
725 |
returned the callback will not be called again. If paAbort is returned the
|
726 |
stream will finish as soon as possible. If paComplete is returned, the stream
|
727 |
will continue until all buffers generated by the callback have been played.
|
728 |
This may be useful in applications such as soundfile players where a specific
|
729 |
duration of output is required. However, it is not necessary to utilise this
|
730 |
mechanism as Pa_StopStream(), Pa_AbortStream() or Pa_CloseStream() can also
|
731 |
be used to stop the stream. The callback must always fill the entire output
|
732 |
buffer irrespective of its return value.
|
733 |
|
734 |
@see Pa_OpenStream, Pa_OpenDefaultStream
|
735 |
|
736 |
@note With the exception of Pa_GetStreamCpuLoad() it is not permissable to call
|
737 |
PortAudio API functions from within the stream callback.
|
738 |
*/
|
739 |
typedef int PaStreamCallback(
|
740 |
const void *input, void *output,
|
741 |
unsigned long frameCount,
|
742 |
const PaStreamCallbackTimeInfo* timeInfo,
|
743 |
PaStreamCallbackFlags statusFlags,
|
744 |
void *userData );
|
745 |
|
746 |
|
747 |
/** Opens a stream for either input, output or both.
|
748 |
|
749 |
@param stream The address of a PaStream pointer which will receive
|
750 |
a pointer to the newly opened stream.
|
751 |
|
752 |
@param inputParameters A structure that describes the input parameters used by
|
753 |
the opened stream. See PaStreamParameters for a description of these parameters.
|
754 |
inputParameters must be NULL for output-only streams.
|
755 |
|
756 |
@param outputParameters A structure that describes the output parameters used by
|
757 |
the opened stream. See PaStreamParameters for a description of these parameters.
|
758 |
outputParameters must be NULL for input-only streams.
|
759 |
|
760 |
@param sampleRate The desired sampleRate. For full-duplex streams it is the
|
761 |
sample rate for both input and output
|
762 |
|
763 |
@param framesPerBuffer The number of frames passed to the stream callback
|
764 |
function, or the preferred block granularity for a blocking read/write stream.
|
765 |
The special value paFramesPerBufferUnspecified (0) may be used to request that
|
766 |
the stream callback will recieve an optimal (and possibly varying) number of
|
767 |
frames based on host requirements and the requested latency settings.
|
768 |
Note: With some host APIs, the use of non-zero framesPerBuffer for a callback
|
769 |
stream may introduce an additional layer of buffering which could introduce
|
770 |
additional latency. PortAudio guarantees that the additional latency
|
771 |
will be kept to the theoretical minimum however, it is strongly recommended
|
772 |
that a non-zero framesPerBuffer value only be used when your algorithm
|
773 |
requires a fixed number of frames per stream callback.
|
774 |
|
775 |
@param streamFlags Flags which modify the behaviour of the streaming process.
|
776 |
This parameter may contain a combination of flags ORed together. Some flags may
|
777 |
only be relevant to certain buffer formats.
|
778 |
|
779 |
@param streamCallback A pointer to a client supplied function that is responsible
|
780 |
for processing and filling input and output buffers. If this parameter is NULL
|
781 |
the stream will be opened in 'blocking read/write' mode. In blocking mode,
|
782 |
the client can receive sample data using Pa_ReadStream and write sample data
|
783 |
using Pa_WriteStream, the number of samples that may be read or written
|
784 |
without blocking is returned by Pa_GetStreamReadAvailable and
|
785 |
Pa_GetStreamWriteAvailable respectively.
|
786 |
|
787 |
@param userData A client supplied pointer which is passed to the stream callback
|
788 |
function. It could for example, contain a pointer to instance data necessary
|
789 |
for processing the audio buffers. This parameter is ignored if streamCallback
|
790 |
is NULL.
|
791 |
|
792 |
@return
|
793 |
Upon success Pa_OpenStream() returns paNoError and places a pointer to a
|
794 |
valid PaStream in the stream argument. The stream is inactive (stopped).
|
795 |
If a call to Pa_OpenStream() fails, a non-zero error code is returned (see
|
796 |
PaError for possible error codes) and the value of stream is invalid.
|
797 |
|
798 |
@see PaStreamParameters, PaStreamCallback, Pa_ReadStream, Pa_WriteStream,
|
799 |
Pa_GetStreamReadAvailable, Pa_GetStreamWriteAvailable
|
800 |
*/
|
801 |
PaError Pa_OpenStream( PaStream** stream,
|
802 |
const PaStreamParameters *inputParameters,
|
803 |
const PaStreamParameters *outputParameters,
|
804 |
double sampleRate,
|
805 |
unsigned long framesPerBuffer,
|
806 |
PaStreamFlags streamFlags,
|
807 |
PaStreamCallback *streamCallback,
|
808 |
void *userData );
|
809 |
|
810 |
|
811 |
/** A simplified version of Pa_OpenStream() that opens the default input
|
812 |
and/or output devices.
|
813 |
|
814 |
@param stream The address of a PaStream pointer which will receive
|
815 |
a pointer to the newly opened stream.
|
816 |
|
817 |
@param numInputChannels The number of channels of sound that will be supplied
|
818 |
to the stream callback or returned by Pa_ReadStream. It can range from 1 to
|
819 |
the value of maxInputChannels in the PaDeviceInfo record for the default input
|
820 |
device. If 0 the stream is opened as an output-only stream.
|
821 |
|
822 |
@param numOutputChannels The number of channels of sound to be delivered to the
|
823 |
stream callback or passed to Pa_WriteStream. It can range from 1 to the value
|
824 |
of maxOutputChannels in the PaDeviceInfo record for the default output dvice.
|
825 |
If 0 the stream is opened as an output-only stream.
|
826 |
|
827 |
@param sampleFormat The sample format of both the input and output buffers
|
828 |
provided to the callback or passed to and from Pa_ReadStream and Pa_WriteStream.
|
829 |
sampleFormat may be any of the formats described by the PaSampleFormat
|
830 |
enumeration.
|
831 |
|
832 |
@param sampleRate Same as Pa_OpenStream parameter of the same name.
|
833 |
@param framesPerBuffer Same as Pa_OpenStream parameter of the same name.
|
834 |
@param streamCallback Same as Pa_OpenStream parameter of the same name.
|
835 |
@param userData Same as Pa_OpenStream parameter of the same name.
|
836 |
|
837 |
@return As for Pa_OpenStream
|
838 |
|
839 |
@see Pa_OpenStream, PaStreamCallback
|
840 |
*/
|
841 |
PaError Pa_OpenDefaultStream( PaStream** stream,
|
842 |
int numInputChannels,
|
843 |
int numOutputChannels,
|
844 |
PaSampleFormat sampleFormat,
|
845 |
double sampleRate,
|
846 |
unsigned long framesPerBuffer,
|
847 |
PaStreamCallback *streamCallback,
|
848 |
void *userData );
|
849 |
|
850 |
|
851 |
/** Closes an audio stream. If the audio stream is active it
|
852 |
discards any pending buffers as if Pa_AbortStream() had been called.
|
853 |
*/
|
854 |
PaError Pa_CloseStream( PaStream *stream );
|
855 |
|
856 |
|
857 |
/** Functions of type PaStreamFinishedCallback are implemented by PortAudio
|
858 |
clients. They can be registered with a stream using the Pa_SetStreamFinishedCallback
|
859 |
function. Once registered they are called when the stream becomes inactive
|
860 |
(ie once a call to Pa_StopStream() will not block).
|
861 |
A stream will become inactive after the stream callback returns non-zero,
|
862 |
or when Pa_StopStream or Pa_AbortStream is called. For a stream providing audio
|
863 |
output, if the stream callback returns paComplete, or Pa_StopStream is called,
|
864 |
the stream finished callback will not be called until all generated sample data
|
865 |
has been played.
|
866 |
|
867 |
@param userData The userData parameter supplied to Pa_OpenStream()
|
868 |
|
869 |
@see Pa_SetStreamFinishedCallback
|
870 |
*/
|
871 |
typedef void PaStreamFinishedCallback( void *userData );
|
872 |
|
873 |
|
874 |
/** Register a stream finished callback function which will be called when the
|
875 |
stream becomes inactive. See the description of PaStreamFinishedCallback for
|
876 |
further details about when the callback will be called.
|
877 |
|
878 |
@param stream a pointer to a PaStream that is in the stopped state - if the
|
879 |
stream is not stopped, the stream's finished callback will remain unchanged
|
880 |
and an error code will be returned.
|
881 |
|
882 |
@param streamFinishedCallback a pointer to a function with the same signature
|
883 |
as PaStreamFinishedCallback, that will be called when the stream becomes
|
884 |
inactive. Passing NULL for this parameter will un-register a previously
|
885 |
registered stream finished callback function.
|
886 |
|
887 |
@return on success returns paNoError, otherwise an error code indicating the cause
|
888 |
of the error.
|
889 |
|
890 |
@see PaStreamFinishedCallback
|
891 |
*/
|
892 |
PaError Pa_SetStreamFinishedCallback( PaStream *stream, PaStreamFinishedCallback* streamFinishedCallback );
|
893 |
|
894 |
|
895 |
/** Commences audio processing.
|
896 |
*/
|
897 |
PaError Pa_StartStream( PaStream *stream );
|
898 |
|
899 |
|
900 |
/** Terminates audio processing. It waits until all pending
|
901 |
audio buffers have been played before it returns.
|
902 |
*/
|
903 |
PaError Pa_StopStream( PaStream *stream );
|
904 |
|
905 |
|
906 |
/** Terminates audio processing immediately without waiting for pending
|
907 |
buffers to complete.
|
908 |
*/
|
909 |
PaError Pa_AbortStream( PaStream *stream );
|
910 |
|
911 |
|
912 |
/** Determine whether the stream is stopped.
|
913 |
A stream is considered to be stopped prior to a successful call to
|
914 |
Pa_StartStream and after a successful call to Pa_StopStream or Pa_AbortStream.
|
915 |
If a stream callback returns a value other than paContinue the stream is NOT
|
916 |
considered to be stopped.
|
917 |
|
918 |
@return Returns one (1) when the stream is stopped, zero (0) when
|
919 |
the stream is running or, a PaErrorCode (which are always negative) if
|
920 |
PortAudio is not initialized or an error is encountered.
|
921 |
|
922 |
@see Pa_StopStream, Pa_AbortStream, Pa_IsStreamActive
|
923 |
*/
|
924 |
PaError Pa_IsStreamStopped( PaStream *stream );
|
925 |
|
926 |
|
927 |
/** Determine whether the stream is active.
|
928 |
A stream is active after a successful call to Pa_StartStream(), until it
|
929 |
becomes inactive either as a result of a call to Pa_StopStream() or
|
930 |
Pa_AbortStream(), or as a result of a return value other than paContinue from
|
931 |
the stream callback. In the latter case, the stream is considered inactive
|
932 |
after the last buffer has finished playing.
|
933 |
|
934 |
@return Returns one (1) when the stream is active (ie playing or recording
|
935 |
audio), zero (0) when not playing or, a PaErrorCode (which are always negative)
|
936 |
if PortAudio is not initialized or an error is encountered.
|
937 |
|
938 |
@see Pa_StopStream, Pa_AbortStream, Pa_IsStreamStopped
|
939 |
*/
|
940 |
PaError Pa_IsStreamActive( PaStream *stream );
|
941 |
|
942 |
|
943 |
|
944 |
/** A structure containing unchanging information about an open stream.
|
945 |
@see Pa_GetStreamInfo
|
946 |
*/
|
947 |
|
948 |
typedef struct PaStreamInfo
|
949 |
{
|
950 |
/** this is struct version 1 */
|
951 |
int structVersion;
|
952 |
|
953 |
/** The input latency of the stream in seconds. This value provides the most
|
954 |
accurate estimate of input latency available to the implementation. It may
|
955 |
differ significantly from the suggestedLatency value passed to Pa_OpenStream().
|
956 |
The value of this field will be zero (0.) for output-only streams.
|
957 |
@see PaTime
|
958 |
*/
|
959 |
PaTime inputLatency;
|
960 |
|
961 |
/** The output latency of the stream in seconds. This value provides the most
|
962 |
accurate estimate of output latency available to the implementation. It may
|
963 |
differ significantly from the suggestedLatency value passed to Pa_OpenStream().
|
964 |
The value of this field will be zero (0.) for input-only streams.
|
965 |
@see PaTime
|
966 |
*/
|
967 |
PaTime outputLatency;
|
968 |
|
969 |
/** The sample rate of the stream in Hertz (samples per second). In cases
|
970 |
where the hardware sample rate is inaccurate and PortAudio is aware of it,
|
971 |
the value of this field may be different from the sampleRate parameter
|
972 |
passed to Pa_OpenStream(). If information about the actual hardware sample
|
973 |
rate is not available, this field will have the same value as the sampleRate
|
974 |
parameter passed to Pa_OpenStream().
|
975 |
*/
|
976 |
double sampleRate;
|
977 |
|
978 |
} PaStreamInfo;
|
979 |
|
980 |
|
981 |
/** Retrieve a pointer to a PaStreamInfo structure containing information
|
982 |
about the specified stream.
|
983 |
@return A pointer to an immutable PaStreamInfo structure. If the stream
|
984 |
parameter invalid, or an error is encountered, the function returns NULL.
|
985 |
|
986 |
@param stream A pointer to an open stream previously created with Pa_OpenStream.
|
987 |
|
988 |
@note PortAudio manages the memory referenced by the returned pointer,
|
989 |
the client must not manipulate or free the memory. The pointer is only
|
990 |
guaranteed to be valid until the specified stream is closed.
|
991 |
|
992 |
@see PaStreamInfo
|
993 |
*/
|
994 |
const PaStreamInfo* Pa_GetStreamInfo( PaStream *stream );
|
995 |
|
996 |
|
997 |
/** Determine the current time for the stream according to the same clock used
|
998 |
to generate buffer timestamps. This time may be used for syncronising other
|
999 |
events to the audio stream, for example synchronizing audio to MIDI.
|
1000 |
|
1001 |
@return The stream's current time in seconds, or 0 if an error occurred.
|
1002 |
|
1003 |
@see PaTime, PaStreamCallback
|
1004 |
*/
|
1005 |
PaTime Pa_GetStreamTime( PaStream *stream );
|
1006 |
|
1007 |
|
1008 |
/** Retrieve CPU usage information for the specified stream.
|
1009 |
The "CPU Load" is a fraction of total CPU time consumed by a callback stream's
|
1010 |
audio processing routines including, but not limited to the client supplied
|
1011 |
stream callback. This function does not work with blocking read/write streams.
|
1012 |
|
1013 |
This function may be called from the stream callback function or the
|
1014 |
application.
|
1015 |
|
1016 |
@return
|
1017 |
A floating point value, typically between 0.0 and 1.0, where 1.0 indicates
|
1018 |
that the stream callback is consuming the maximum number of CPU cycles possible
|
1019 |
to maintain real-time operation. A value of 0.5 would imply that PortAudio and
|
1020 |
the stream callback was consuming roughly 50% of the available CPU time. The
|
1021 |
return value may exceed 1.0. A value of 0.0 will always be returned for a
|
1022 |
blocking read/write stream, or if an error occurrs.
|
1023 |
*/
|
1024 |
double Pa_GetStreamCpuLoad( PaStream* stream );
|
1025 |
|
1026 |
|
1027 |
/** Read samples from an input stream. The function doesn't return until
|
1028 |
the entire buffer has been filled - this may involve waiting for the operating
|
1029 |
system to supply the data.
|
1030 |
|
1031 |
@param stream A pointer to an open stream previously created with Pa_OpenStream.
|
1032 |
|
1033 |
@param buffer A pointer to a buffer of sample frames. The buffer contains
|
1034 |
samples in the format specified by the inputParameters->sampleFormat field
|
1035 |
used to open the stream, and the number of channels specified by
|
1036 |
inputParameters->numChannels. If non-interleaved samples were requested,
|
1037 |
buffer is a pointer to the first element of an array of non-interleaved
|
1038 |
buffer pointers, one for each channel.
|
1039 |
|
1040 |
@param frames The number of frames to be read into buffer. This parameter
|
1041 |
is not constrained to a specific range, however high performance applications
|
1042 |
will want to match this parameter to the framesPerBuffer parameter used
|
1043 |
when opening the stream.
|
1044 |
|
1045 |
@return On success PaNoError will be returned, or PaInputOverflowed if input
|
1046 |
data was discarded by PortAudio after the previous call and before this call.
|
1047 |
*/
|
1048 |
PaError Pa_ReadStream( PaStream* stream,
|
1049 |
void *buffer,
|
1050 |
unsigned long frames );
|
1051 |
|
1052 |
|
1053 |
/** Write samples to an output stream. This function doesn't return until the
|
1054 |
entire buffer has been consumed - this may involve waiting for the operating
|
1055 |
system to consume the data.
|
1056 |
|
1057 |
@param stream A pointer to an open stream previously created with Pa_OpenStream.
|
1058 |
|
1059 |
@param buffer A pointer to a buffer of sample frames. The buffer contains
|
1060 |
samples in the format specified by the outputParameters->sampleFormat field
|
1061 |
used to open the stream, and the number of channels specified by
|
1062 |
outputParameters->numChannels. If non-interleaved samples were requested,
|
1063 |
buffer is a pointer to the first element of an array of non-interleaved
|
1064 |
buffer pointers, one for each channel.
|
1065 |
|
1066 |
@param frames The number of frames to be written from buffer. This parameter
|
1067 |
is not constrained to a specific range, however high performance applications
|
1068 |
will want to match this parameter to the framesPerBuffer parameter used
|
1069 |
when opening the stream.
|
1070 |
|
1071 |
@return On success PaNoError will be returned, or paOutputUnderflowed if
|
1072 |
additional output data was inserted after the previous call and before this
|
1073 |
call.
|
1074 |
*/
|
1075 |
PaError Pa_WriteStream( PaStream* stream,
|
1076 |
const void *buffer,
|
1077 |
unsigned long frames );
|
1078 |
|
1079 |
|
1080 |
/** Retrieve the number of frames that can be read from the stream without
|
1081 |
waiting.
|
1082 |
|
1083 |
@return Returns a non-negative value representing the maximum number of frames
|
1084 |
that can be read from the stream without blocking or busy waiting or, a
|
1085 |
PaErrorCode (which are always negative) if PortAudio is not initialized or an
|
1086 |
error is encountered.
|
1087 |
*/
|
1088 |
signed long Pa_GetStreamReadAvailable( PaStream* stream );
|
1089 |
|
1090 |
|
1091 |
/** Retrieve the number of frames that can be written to the stream without
|
1092 |
waiting.
|
1093 |
|
1094 |
@return Returns a non-negative value representing the maximum number of frames
|
1095 |
that can be written to the stream without blocking or busy waiting or, a
|
1096 |
PaErrorCode (which are always negative) if PortAudio is not initialized or an
|
1097 |
error is encountered.
|
1098 |
*/
|
1099 |
signed long Pa_GetStreamWriteAvailable( PaStream* stream );
|
1100 |
|
1101 |
|
1102 |
/* Miscellaneous utilities */
|
1103 |
|
1104 |
|
1105 |
/** Retrieve the size of a given sample format in bytes.
|
1106 |
|
1107 |
@return The size in bytes of a single sample in the specified format,
|
1108 |
or paSampleFormatNotSupported if the format is not supported.
|
1109 |
*/
|
1110 |
PaError Pa_GetSampleSize( PaSampleFormat format );
|
1111 |
|
1112 |
|
1113 |
/** Put the caller to sleep for at least 'msec' milliseconds. This function is
|
1114 |
provided only as a convenience for authors of portable code (such as the tests
|
1115 |
and examples in the PortAudio distribution.)
|
1116 |
|
1117 |
The function may sleep longer than requested so don't rely on this for accurate
|
1118 |
musical timing.
|
1119 |
*/
|
1120 |
void Pa_Sleep( long msec );
|
1121 |
|
1122 |
|
1123 |
|
1124 |
#ifdef __cplusplus
|
1125 |
}
|
1126 |
#endif /* __cplusplus */
|
1127 |
#endif /* PORTAUDIO_H */
|