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- Committer: Bazaar Package Importer
- Author(s): Samuel Thibault
- Date: 2010-08-01 22:30:18 UTC
- Revision ID: james.westby@ubuntu.com-20100801223018-6p7yxlp20l3fgwvw
Tags: 1.43.03-2
* debian/control:
- Bump Standards-Version to 3.9.0 (no change needed).
* debian/patches/big-endian.diff: New patch to fix phoneme index on
big-endian machines (Closes: #585654).
* debian/rules: Use portaudio19.h for building, but revert to upstream
portaudio18.h on cleaning.
- Bump Standards-Version to 3.9.0 (no change needed).
* debian/patches/big-endian.diff: New patch to fix phoneme index on
big-endian machines (Closes: #585654).
* debian/rules: Use portaudio19.h for building, but revert to upstream
portaudio18.h on cleaning.
- files added:
- .pc
- .pc/big-endian.diff
- .pc/big-endian.diff/platforms
- .pc/big-endian.diff/platforms/big_endian
- debian/patches
- debian/source
- files modified:
- debian/changelog
added
removed
src/portaudio.h
1
// 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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// NOTE: Copy this file to portaudio.h in order to compile with V18 portaudio
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#ifndef PORT_AUDIO_H
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#define PORT_AUDIO_H
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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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/*
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* $Id: portaudio.h 1061 2006-06-19 22:46:41Z lschwardt $
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* $Id: portaudio.h,v 1.5 2002/03/26 18:04:22 philburk Exp $
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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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* Latest version available at: http://www.audiomulch.com/portaudio/
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*
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* Copyright (c) 1999-2002 Ross Bencina and Phil Burk
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* Copyright (c) 1999-2000 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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* 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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*/
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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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64
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typedef int PaError;
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typedef enum PaErrorCode
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{
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typedef enum {
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paNoError = 0,
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paNotInitialized = -10000,
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paUnanticipatedHostError,
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paHostError = -10000,
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paInvalidChannelCount,
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paInvalidSampleRate,
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paInvalidDevice,
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paInvalidDeviceId,
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paInvalidFlag,
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paSampleFormatNotSupported,
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paBadIODeviceCombination,
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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
102
message.
103
*/
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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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paDeviceUnavailable
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} PaErrorNum;
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66
/*
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Pa_Initialize() is the library initialisation function - call this before
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using the library.
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70
*/
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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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Pa_Terminate() is the library termination function - call this after
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using the library.
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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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*/
162
#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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*/
170
#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
251
*/
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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.
257
*/
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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.
263
*/
264
PaDeviceIndex defaultOutputDevice;
265
266
} 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().
281
*/
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const PaHostApiInfo * Pa_GetHostApiInfo( PaHostApiIndex hostApi );
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284
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/** Convert a static host API unique identifier, into a runtime
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host API index.
287
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@param type A unique host API identifier belonging to the PaHostApiTypeId
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enumeration.
290
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@return A valid PaHostApiIndex ranging from 0 to (Pa_GetHostApiCount()-1) or,
292
a PaErrorCode (which are always negative) if PortAudio is not initialized
293
or an error is encountered.
294
295
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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@see PaHostApiTypeId
299
*/
300
PaHostApiIndex Pa_HostApiTypeIdToHostApiIndex( PaHostApiTypeId type );
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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.
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@param hostApi A valid host API index ranging from 0 to (Pa_GetHostApiCount()-1)
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@param hostApiDeviceIndex A valid per-host device index in the range
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0 to (Pa_GetHostApiInfo(hostApi)->deviceCount-1)
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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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A paInvalidHostApi error code indicates that the host API index specified by
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the hostApi parameter is out of range.
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A paInvalidDevice error code indicates that the hostApiDeviceIndex parameter
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is out of range.
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@see PaHostApiInfo
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*/
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PaDeviceIndex Pa_HostApiDeviceIndexToDeviceIndex( PaHostApiIndex hostApi,
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int hostApiDeviceIndex );
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/** 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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/** Return information about the last host error encountered. The error
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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.
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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 );
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/* Device enumeration and capabilities */
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/** Retrieve the number of available devices. The number of available devices
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may be zero.
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@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 );
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366
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/** Retrieve the index of the default input device. The result can be
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used in the inputDevice parameter to Pa_OpenStream().
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@return The default input device index for the default host API, or paNoDevice
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if no default input device is available or an error was encountered.
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*/
373
PaDeviceIndex Pa_GetDefaultInputDevice( void );
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/** 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
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if no default output device is available or an error was encountered.
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382
@note
383
On the PC, the user can specify a default device by
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setting an environment variable. For example, to use device #1.
385
<pre>
386
set PA_RECOMMENDED_OUTPUT_DEVICE=1
387
</pre>
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The user should first determine the available device ids by using
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the supplied application "pa_devs".
390
*/
391
PaDeviceIndex Pa_GetDefaultOutputDevice( void );
392
393
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/** 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
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PaStreamCallback and as the result of Pa_GetStreamTime().
397
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@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
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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.
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The floating point representation (paFloat32) uses +1.0 and -1.0 as the
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/*
83
Pa_GetHostError() returns a host specific error code.
84
This can be called after receiving a PortAudio error code of paHostError.
85
86
*/
87
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long Pa_GetHostError( void );
89
90
/*
91
Pa_GetErrorText() translates the supplied PortAudio error number
92
into a human readable message.
93
94
*/
95
96
const char *Pa_GetErrorText( PaError errnum );
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/*
99
Sample formats
100
101
These are formats used to pass sound data between the callback and the
102
stream. Each device has a "native" format which may be used when optimum
103
efficiency or control over conversion is required.
104
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Formats marked "always available" are supported (emulated) by all
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PortAudio implementations.
107
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The floating point representation (paFloat32) uses +1.0 and -1.0 as the
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maximum and minimum respectively.
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paUInt8 is an unsigned 8 bit format where 128 is considered "ground"
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The paNonInterleaved flag indicates that a multichannel buffer is passed
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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
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*/
114
422
115
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.
116
#define paFloat32 ((PaSampleFormat) (1<<0)) /*always available*/
117
#define paInt16 ((PaSampleFormat) (1<<1)) /*always available*/
118
#define paInt32 ((PaSampleFormat) (1<<2)) /*always available*/
119
#define paInt24 ((PaSampleFormat) (1<<3))
120
#define paPackedInt24 ((PaSampleFormat) (1<<4))
121
#define paInt8 ((PaSampleFormat) (1<<5))
122
#define paUInt8 ((PaSampleFormat) (1<<6))
123
#define paCustomFormat ((PaSampleFormat) (1<<16))
124
125
/*
126
Device enumeration mechanism.
127
128
Device ids range from 0 to Pa_CountDevices()-1.
129
130
Devices may support input, output or both.
131
437
132
*/
438
typedef struct PaDeviceInfo
133
134
typedef int PaDeviceID;
135
#define paNoDevice -1
136
137
int Pa_CountDevices( void );
138
139
typedef struct
439
140
{
440
int structVersion; /* this is struct version 2 */
141
int structVersion;
441
142
const char *name;
442
PaHostApiIndex hostApi; /* note this is a host API index, not a type id*/
443
444
143
int maxInputChannels;
445
144
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,
145
/* Number of discrete rates, or -1 if range supported. */
146
int numSampleRates;
147
/* Array of supported sample rates, or {min,max} if range supported. */
148
const double *sampleRates;
149
PaSampleFormat nativeSampleFormats;
150
}
151
PaDeviceInfo;
152
153
/*
154
Pa_GetDefaultInputDeviceID(), Pa_GetDefaultOutputDeviceID() return the
155
default device ids for input and output respectively, or paNoDevice if
156
no device is available.
157
The result can be passed to Pa_OpenStream().
158
159
On the PC, the user can specify a default device by
160
setting an environment variable. For example, to use device #1.
161
162
set PA_RECOMMENDED_OUTPUT_DEVICE=1
163
164
The user should first determine the available device ids by using
165
the supplied application "pa_devs".
166
167
*/
168
169
PaDeviceID Pa_GetDefaultInputDeviceID( void );
170
PaDeviceID Pa_GetDefaultOutputDeviceID( void );
171
172
173
174
/*
175
Pa_GetDeviceInfo() returns a pointer to an immutable PaDeviceInfo structure
176
for the device specified.
177
If the device parameter is out of range the function returns NULL.
178
179
PortAudio manages the memory referenced by the returned pointer, the client
180
must not manipulate or free the memory. The pointer is only guaranteed to be
181
valid between calls to Pa_Initialize() and Pa_Terminate().
182
183
*/
184
185
const PaDeviceInfo* Pa_GetDeviceInfo( PaDeviceID device );
186
187
/*
188
PaTimestamp is used to represent a continuous sample clock with arbitrary
189
start time that can be used for syncronization. The type is used for the
190
outTime argument to the PortAudioCallback and as the result of Pa_StreamTime()
191
192
*/
193
194
typedef double PaTimestamp;
195
196
/*
197
PortAudioCallback is implemented by PortAudio clients.
198
199
inputBuffer and outputBuffer are arrays of interleaved samples,
701
200
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
201
determined by parameters to Pa_OpenStream() (see below).
202
203
framesPerBuffer is the number of sample frames to be processed by the callback.
204
205
outTime is the time in samples when the buffer(s) processed by
206
this callback will begin being played at the audio output.
207
See also Pa_StreamTime()
208
209
userData is the value of a user supplied pointer passed to Pa_OpenStream()
210
intended for storing synthesis data etc.
211
212
return value:
213
The callback can return a non-zero value to stop the stream. This may be
214
useful in applications such as soundfile players where a specific duration
215
of output is required. However, it is not necessary to utilise this mechanism
216
as StopStream() will also terminate the stream. A callback returning a
217
non-zero value must fill the entire outputBuffer.
218
219
NOTE: None of the other stream functions may be called from within the
220
callback function except for Pa_GetCPULoad().
221
222
*/
223
224
typedef int (PortAudioCallback)(
225
void *inputBuffer, void *outputBuffer,
226
unsigned long framesPerBuffer,
227
PaTimestamp outTime, void *userData );
228
229
230
/*
231
Stream flags
232
233
These flags may be supplied (ored together) in the streamFlags argument to
234
the Pa_OpenStream() function.
235
236
*/
237
238
#define paNoFlag (0)
239
#define paClipOff (1<<0) /* disable default clipping of out of range samples */
240
#define paDitherOff (1<<1) /* disable default dithering */
241
#define paPlatformSpecificFlags (0x00010000)
242
typedef unsigned long PaStreamFlags;
243
244
/*
245
A single PortAudioStream provides multiple channels of real-time
246
input and output audio streaming to a client application.
247
Pointers to PortAudioStream objects are passed between PortAudio functions.
248
*/
249
250
typedef void PortAudioStream;
251
#define PaStream PortAudioStream
252
253
/*
254
Pa_OpenStream() opens a stream for either input, output or both.
255
256
stream is the address of a PortAudioStream pointer which will receive
750
257
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
258
259
inputDevice is the id of the device used for input (see PaDeviceID above.)
260
inputDevice may be paNoDevice to indicate that an input device is not required.
261
262
numInputChannels is the number of channels of sound to be delivered to the
263
callback. It can range from 1 to the value of maxInputChannels in the
264
PaDeviceInfo record for the device specified by the inputDevice parameter.
265
If inputDevice is paNoDevice numInputChannels is ignored.
266
267
inputSampleFormat is the sample format of inputBuffer provided to the callback
268
function. inputSampleFormat may be any of the formats described by the
269
PaSampleFormat enumeration (see above). PortAudio guarantees support for
270
the device's native formats (nativeSampleFormats in the device info record)
271
and additionally 16 and 32 bit integer and 32 bit floating point formats.
272
Support for other formats is implementation defined.
273
274
inputDriverInfo is a pointer to an optional driver specific data structure
275
containing additional information for device setup or stream processing.
276
inputDriverInfo is never required for correct operation. If not used
277
inputDriverInfo should be NULL.
278
279
outputDevice is the id of the device used for output (see PaDeviceID above.)
280
outputDevice may be paNoDevice to indicate that an output device is not required.
281
282
numOutputChannels is the number of channels of sound to be supplied by the
283
callback. See the definition of numInputChannels above for more details.
284
285
outputSampleFormat is the sample format of the outputBuffer filled by the
286
callback function. See the definition of inputSampleFormat above for more
287
details.
288
289
outputDriverInfo is a pointer to an optional driver specific data structure
290
containing additional information for device setup or stream processing.
291
outputDriverInfo is never required for correct operation. If not used
292
outputDriverInfo should be NULL.
293
294
sampleRate is the desired sampleRate. For full-duplex streams it is the
761
295
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
296
297
framesPerBuffer is the length in sample frames of all internal sample buffers
298
used for communication with platform specific audio routines. Wherever
299
possible this corresponds to the framesPerBuffer parameter passed to the
300
callback function.
301
302
numberOfBuffers is the number of buffers used for multibuffered communication
303
with the platform specific audio routines. If you pass zero, then an optimum
304
value will be chosen for you internally. This parameter is provided only
305
as a guide - and does not imply that an implementation must use multibuffered
306
i/o when reliable double buffering is available (such as SndPlayDoubleBuffer()
307
on the Macintosh.)
308
309
streamFlags may contain a combination of flags ORed together.
310
These flags modify the behaviour of the streaming process. Some flags may only
311
be relevant to certain buffer formats.
312
313
callback is a pointer to a client supplied function that is responsible
314
for processing and filling input and output buffers (see above for details.)
315
316
userData is a client supplied pointer which is passed to the callback
788
317
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.
318
for processing the audio buffers.
319
320
return value:
321
Upon success Pa_OpenStream() returns PaNoError and places a pointer to a
322
valid PortAudioStream in the stream argument. The stream is inactive (stopped).
323
If a call to Pa_OpenStream() fails a non-zero error code is returned (see
324
PaError above) and the value of stream is invalid.
325
326
*/
797
327
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,
328
PaError Pa_OpenStream( PortAudioStream** stream,
329
PaDeviceID inputDevice,
330
int numInputChannels,
331
PaSampleFormat inputSampleFormat,
332
void *inputDriverInfo,
333
PaDeviceID outputDevice,
334
int numOutputChannels,
335
PaSampleFormat outputSampleFormat,
336
void *outputDriverInfo,
804
337
double sampleRate,
805
338
unsigned long framesPerBuffer,
339
unsigned long numberOfBuffers,
806
340
PaStreamFlags streamFlags,
807
PaStreamCallback *streamCallback,
341
PortAudioCallback *callback,
808
342
void *userData );
809
343
810
344
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
345
/*
346
Pa_OpenDefaultStream() is a simplified version of Pa_OpenStream() that opens
347
the default input and/or output devices. Most parameters have identical meaning
348
to their Pa_OpenStream() counterparts, with the following exceptions:
349
350
If either numInputChannels or numOutputChannels is 0 the respective device
351
is not opened. This has the same effect as passing paNoDevice in the device
352
arguments to Pa_OpenStream().
353
354
sampleFormat applies to both the input and output buffers.
355
840
356
*/
841
PaError Pa_OpenDefaultStream( PaStream** stream,
357
358
PaError Pa_OpenDefaultStream( PortAudioStream** stream,
842
359
int numInputChannels,
843
360
int numOutputChannels,
844
361
PaSampleFormat sampleFormat,
845
362
double sampleRate,
846
363
unsigned long framesPerBuffer,
847
PaStreamCallback *streamCallback,
364
unsigned long numberOfBuffers,
365
PortAudioCallback *callback,
848
366
void *userData );
849
367
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
368
/*
369
Pa_CloseStream() closes an audio stream, flushing any pending buffers.
370
371
*/
372
373
PaError Pa_CloseStream( PortAudioStream* );
374
375
/*
376
Pa_StartStream() and Pa_StopStream() begin and terminate audio processing.
377
Pa_StopStream() waits until all pending audio buffers have been played.
378
Pa_AbortStream() stops playing immediately without waiting for pending
907
379
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
380
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
381
*/
382
383
PaError Pa_StartStream( PortAudioStream *stream );
384
385
PaError Pa_StopStream( PortAudioStream *stream );
386
387
PaError Pa_AbortStream( PortAudioStream *stream );
388
389
/*
390
Pa_StreamActive() returns one (1) when the stream is active (ie playing
391
or recording audio), zero (0) when not playing, or a negative error number
392
if the stream is invalid.
393
The stream is active between calls to Pa_StartStream() and Pa_StopStream(),
394
but may also become inactive if the callback returns a non-zero value.
395
In the latter case, the stream is considered inactive after the last
396
buffer has finished playing.
397
398
*/
399
400
PaError Pa_StreamActive( PortAudioStream *stream );
401
402
/*
403
Pa_StreamTime() returns the current output time in samples for the stream.
404
This time may be used as a time reference (for example synchronizing audio to
405
MIDI).
406
407
*/
408
409
PaTimestamp Pa_StreamTime( PortAudioStream *stream );
410
411
/*
412
Pa_GetCPULoad() returns the CPU Load for the stream.
413
The "CPU Load" is a fraction of total CPU time consumed by the stream's
1010
414
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
*/
415
callback.
416
A value of 0.5 would imply that PortAudio and the sound generating
417
callback was consuming roughly 50% of the available CPU time.
418
This function may be called from the callback function or the application.
419
420
*/
421
422
double Pa_GetCPULoad( PortAudioStream* stream );
423
424
/*
425
Pa_GetMinNumBuffers() returns the minimum number of buffers required by
426
the current host based on minimum latency.
427
On the PC, for the DirectSound implementation, latency can be optionally set
428
by user by setting an environment variable.
429
For example, to set latency to 200 msec, put:
430
431
set PA_MIN_LATENCY_MSEC=200
432
433
in the AUTOEXEC.BAT file and reboot.
434
If the environment variable is not set, then the latency will be determined
435
based on the OS. Windows NT has higher latency than Win95.
436
437
*/
438
439
int Pa_GetMinNumBuffers( int framesPerBuffer, double sampleRate );
440
441
/*
442
Pa_Sleep() puts the caller to sleep for at least 'msec' milliseconds.
443
You may sleep longer than the requested time so don't rely on this for
444
accurate musical timing.
445
446
Pa_Sleep() is provided as a convenience for authors of portable code (such as
447
the tests and examples in the PortAudio distribution.)
448
449
*/
450
451
void Pa_Sleep( long msec );
452
453
/*
454
Pa_GetSampleSize() returns the size in bytes of a single sample in the
455
supplied PaSampleFormat, or paSampleFormatNotSupported if the format is
456
no supported.
457
458
*/
459
1110
460
PaError Pa_GetSampleSize( PaSampleFormat format );
1111
461
1112
462
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
463
#ifdef __cplusplus
1125
464
}
1126
465
#endif /* __cplusplus */
1127
#endif /* PORTAUDIO_H */
466
#endif /* PORT_AUDIO_H */
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