-#ifndef PORTAUDIO_H
-#define PORTAUDIO_H
-/*
- * $Id: portaudio.h 1745 2011-08-25 17:44:01Z rossb $
- * PortAudio Portable Real-Time Audio Library
- * PortAudio API Header File
- * Latest version available at: http://www.portaudio.com/
- *
- * Copyright (c) 1999-2002 Ross Bencina and Phil Burk
- *
- * Permission is hereby granted, free of charge, to any person obtaining
- * a copy of this software and associated documentation files
- * (the "Software"), to deal in the Software without restriction,
- * including without limitation the rights to use, copy, modify, merge,
- * publish, distribute, sublicense, and/or sell copies of the Software,
- * and to permit persons to whom the Software is furnished to do so,
- * subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be
- * included in all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
- * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
- * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
- * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
- * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
- * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
- * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- */
-
-/*
- * The text above constitutes the entire PortAudio license; however,
- * the PortAudio community also makes the following non-binding requests:
- *
- * Any person wishing to distribute modifications to the Software is
- * requested to send the modifications to the original developer so that
- * they can be incorporated into the canonical version. It is also
- * requested that these non-binding requests be included along with the
- * license above.
- */
-
-/** @file
- @ingroup public_header
- @brief The portable PortAudio API.
-*/
-
-
-#ifdef __cplusplus
-extern "C"
-{
-#endif /* __cplusplus */
-
-
-/** Retrieve the release number of the currently running PortAudio build,
- eg 1900.
-*/
-int Pa_GetVersion( void );
-
-
-/** Retrieve a textual description of the current PortAudio build,
- eg "PortAudio V19-devel 13 October 2002".
-*/
-const char* Pa_GetVersionText( void );
-
-
-/** Error codes returned by PortAudio functions.
- Note that with the exception of paNoError, all PaErrorCodes are negative.
-*/
-
-typedef int PaError;
-typedef enum PaErrorCode
-{
- paNoError = 0,
-
- paNotInitialized = -10000,
- paUnanticipatedHostError,
- paInvalidChannelCount,
- paInvalidSampleRate,
- paInvalidDevice,
- paInvalidFlag,
- paSampleFormatNotSupported,
- paBadIODeviceCombination,
- paInsufficientMemory,
- paBufferTooBig,
- paBufferTooSmall,
- paNullCallback,
- paBadStreamPtr,
- paTimedOut,
- paInternalError,
- paDeviceUnavailable,
- paIncompatibleHostApiSpecificStreamInfo,
- paStreamIsStopped,
- paStreamIsNotStopped,
- paInputOverflowed,
- paOutputUnderflowed,
- paHostApiNotFound,
- paInvalidHostApi,
- paCanNotReadFromACallbackStream,
- paCanNotWriteToACallbackStream,
- paCanNotReadFromAnOutputOnlyStream,
- paCanNotWriteToAnInputOnlyStream,
- paIncompatibleStreamHostApi,
- paBadBufferPtr
-} PaErrorCode;
-
-
-/** Translate the supplied PortAudio error code into a human readable
- message.
-*/
-const char *Pa_GetErrorText( PaError errorCode );
-
-
-/** Library initialization function - call this before using PortAudio.
- This function initializes internal data structures and prepares underlying
- host APIs for use. With the exception of Pa_GetVersion(), Pa_GetVersionText(),
- and Pa_GetErrorText(), this function MUST be called before using any other
- PortAudio API functions.
-
- If Pa_Initialize() is called multiple times, each successful
- call must be matched with a corresponding call to Pa_Terminate().
- Pairs of calls to Pa_Initialize()/Pa_Terminate() may overlap, and are not
- required to be fully nested.
-
- Note that if Pa_Initialize() returns an error code, Pa_Terminate() should
- NOT be called.
-
- @return paNoError if successful, otherwise an error code indicating the cause
- of failure.
-
- @see Pa_Terminate
-*/
-PaError Pa_Initialize( void );
-
-
-/** Library termination function - call this when finished using PortAudio.
- This function deallocates all resources allocated by PortAudio since it was
- initialized by a call to Pa_Initialize(). In cases where Pa_Initialise() has
- been called multiple times, each call must be matched with a corresponding call
- to Pa_Terminate(). The final matching call to Pa_Terminate() will automatically
- close any PortAudio streams that are still open.
-
- Pa_Terminate() MUST be called before exiting a program which uses PortAudio.
- Failure to do so may result in serious resource leaks, such as audio devices
- not being available until the next reboot.
-
- @return paNoError if successful, otherwise an error code indicating the cause
- of failure.
-
- @see Pa_Initialize
-*/
-PaError Pa_Terminate( void );
-
-
-
-/** The type used to refer to audio devices. Values of this type usually
- range from 0 to (Pa_GetDeviceCount()-1), and may also take on the PaNoDevice
- and paUseHostApiSpecificDeviceSpecification values.
-
- @see Pa_GetDeviceCount, paNoDevice, paUseHostApiSpecificDeviceSpecification
-*/
-typedef int PaDeviceIndex;
-
-
-/** A special PaDeviceIndex value indicating that no device is available,
- or should be used.
-
- @see PaDeviceIndex
-*/
-#define paNoDevice ((PaDeviceIndex)-1)
-
-
-/** A special PaDeviceIndex value indicating that the device(s) to be used
- are specified in the host api specific stream info structure.
-
- @see PaDeviceIndex
-*/
-#define paUseHostApiSpecificDeviceSpecification ((PaDeviceIndex)-2)
-
-
-/* Host API enumeration mechanism */
-
-/** The type used to enumerate to host APIs at runtime. Values of this type
- range from 0 to (Pa_GetHostApiCount()-1).
-
- @see Pa_GetHostApiCount
-*/
-typedef int PaHostApiIndex;
-
-
-/** Retrieve the number of available host APIs. Even if a host API is
- available it may have no devices available.
-
- @return A non-negative value indicating the number of available host APIs
- or, a PaErrorCode (which are always negative) if PortAudio is not initialized
- or an error is encountered.
-
- @see PaHostApiIndex
-*/
-PaHostApiIndex Pa_GetHostApiCount( void );
-
-
-/** Retrieve the index of the default host API. The default host API will be
- the lowest common denominator host API on the current platform and is
- unlikely to provide the best performance.
-
- @return A non-negative value ranging from 0 to (Pa_GetHostApiCount()-1)
- indicating the default host API index or, a PaErrorCode (which are always
- negative) if PortAudio is not initialized or an error is encountered.
-*/
-PaHostApiIndex Pa_GetDefaultHostApi( void );
-
-
-/** Unchanging unique identifiers for each supported host API. This type
- is used in the PaHostApiInfo structure. The values are guaranteed to be
- unique and to never change, thus allowing code to be written that
- conditionally uses host API specific extensions.
-
- New type ids will be allocated when support for a host API reaches
- "public alpha" status, prior to that developers should use the
- paInDevelopment type id.
-
- @see PaHostApiInfo
-*/
-typedef enum PaHostApiTypeId
-{
- paInDevelopment=0, /* use while developing support for a new host API */
- paDirectSound=1,
- paMME=2,
- paASIO=3,
- paSoundManager=4,
- paCoreAudio=5,
- paOSS=7,
- paALSA=8,
- paAL=9,
- paBeOS=10,
- paWDMKS=11,
- paJACK=12,
- paWASAPI=13,
- paAudioScienceHPI=14
-} PaHostApiTypeId;
-
-
-/** A structure containing information about a particular host API. */
-
-typedef struct PaHostApiInfo
-{
- /** this is struct version 1 */
- int structVersion;
- /** The well known unique identifier of this host API @see PaHostApiTypeId */
- PaHostApiTypeId type;
- /** A textual description of the host API for display on user interfaces. */
- const char *name;
-
- /** The number of devices belonging to this host API. This field may be
- used in conjunction with Pa_HostApiDeviceIndexToDeviceIndex() to enumerate
- all devices for this host API.
- @see Pa_HostApiDeviceIndexToDeviceIndex
- */
- int deviceCount;
-
- /** The default input device for this host API. The value will be a
- device index ranging from 0 to (Pa_GetDeviceCount()-1), or paNoDevice
- if no default input device is available.
- */
- PaDeviceIndex defaultInputDevice;
-
- /** The default output device for this host API. The value will be a
- device index ranging from 0 to (Pa_GetDeviceCount()-1), or paNoDevice
- if no default output device is available.
- */
- PaDeviceIndex defaultOutputDevice;
-
-} PaHostApiInfo;
-
-
-/** Retrieve a pointer to a structure containing information about a specific
- host Api.
-
- @param hostApi A valid host API index ranging from 0 to (Pa_GetHostApiCount()-1)
-
- @return A pointer to an immutable PaHostApiInfo structure describing
- a specific host API. If the hostApi parameter is out of range or an error
- is encountered, the function returns NULL.
-
- The returned structure is owned by the PortAudio implementation and must not
- be manipulated or freed. The pointer is only guaranteed to be valid between
- calls to Pa_Initialize() and Pa_Terminate().
-*/
-const PaHostApiInfo * Pa_GetHostApiInfo( PaHostApiIndex hostApi );
-
-
-/** Convert a static host API unique identifier, into a runtime
- host API index.
-
- @param type A unique host API identifier belonging to the PaHostApiTypeId
- enumeration.
-
- @return A valid PaHostApiIndex ranging from 0 to (Pa_GetHostApiCount()-1) or,
- a PaErrorCode (which are always negative) if PortAudio is not initialized
- or an error is encountered.
-
- The paHostApiNotFound error code indicates that the host API specified by the
- type parameter is not available.
-
- @see PaHostApiTypeId
-*/
-PaHostApiIndex Pa_HostApiTypeIdToHostApiIndex( PaHostApiTypeId type );
-
-
-/** Convert a host-API-specific device index to standard PortAudio device index.
- This function may be used in conjunction with the deviceCount field of
- PaHostApiInfo to enumerate all devices for the specified host API.
-
- @param hostApi A valid host API index ranging from 0 to (Pa_GetHostApiCount()-1)
-
- @param hostApiDeviceIndex A valid per-host device index in the range
- 0 to (Pa_GetHostApiInfo(hostApi)->deviceCount-1)
-
- @return A non-negative PaDeviceIndex ranging from 0 to (Pa_GetDeviceCount()-1)
- or, a PaErrorCode (which are always negative) if PortAudio is not initialized
- or an error is encountered.
-
- A paInvalidHostApi error code indicates that the host API index specified by
- the hostApi parameter is out of range.
-
- A paInvalidDevice error code indicates that the hostApiDeviceIndex parameter
- is out of range.
-
- @see PaHostApiInfo
-*/
-PaDeviceIndex Pa_HostApiDeviceIndexToDeviceIndex( PaHostApiIndex hostApi,
- int hostApiDeviceIndex );
-
-
-
-/** Structure used to return information about a host error condition.
-*/
-typedef struct PaHostErrorInfo{
- PaHostApiTypeId hostApiType; /**< the host API which returned the error code */
- long errorCode; /**< the error code returned */
- const char *errorText; /**< a textual description of the error if available, otherwise a zero-length string */
-}PaHostErrorInfo;
-
-
-/** Return information about the last host error encountered. The error
- information returned by Pa_GetLastHostErrorInfo() will never be modified
- asynchronously by errors occurring in other PortAudio owned threads
- (such as the thread that manages the stream callback.)
-
- This function is provided as a last resort, primarily to enhance debugging
- by providing clients with access to all available error information.
-
- @return A pointer to an immutable structure constraining information about
- the host error. The values in this structure will only be valid if a
- PortAudio function has previously returned the paUnanticipatedHostError
- error code.
-*/
-const PaHostErrorInfo* Pa_GetLastHostErrorInfo( void );
-
-
-
-/* Device enumeration and capabilities */
-
-/** Retrieve the number of available devices. The number of available devices
- may be zero.
-
- @return A non-negative value indicating the number of available devices or,
- a PaErrorCode (which are always negative) if PortAudio is not initialized
- or an error is encountered.
-*/
-PaDeviceIndex Pa_GetDeviceCount( void );
-
-
-/** Retrieve the index of the default input device. The result can be
- used in the inputDevice parameter to Pa_OpenStream().
-
- @return The default input device index for the default host API, or paNoDevice
- if no default input device is available or an error was encountered.
-*/
-PaDeviceIndex Pa_GetDefaultInputDevice( void );
-
-
-/** Retrieve the index of the default output device. The result can be
- used in the outputDevice parameter to Pa_OpenStream().
-
- @return The default output device index for the default host API, or paNoDevice
- if no default output device is available or an error was encountered.
-
- @note
- On the PC, the user can specify a default device by
- setting an environment variable. For example, to use device #1.
-<pre>
- set PA_RECOMMENDED_OUTPUT_DEVICE=1
-</pre>
- The user should first determine the available device ids by using
- the supplied application "pa_devs".
-*/
-PaDeviceIndex Pa_GetDefaultOutputDevice( void );
-
-
-/** The type used to represent monotonic time in seconds. PaTime is
- used for the fields of the PaStreamCallbackTimeInfo argument to the
- PaStreamCallback and as the result of Pa_GetStreamTime().
-
- PaTime values have unspecified origin.
-
- @see PaStreamCallback, PaStreamCallbackTimeInfo, Pa_GetStreamTime
-*/
-typedef double PaTime;
-
-
-/** A type used to specify one or more sample formats. Each value indicates
- a possible format for sound data passed to and from the stream callback,
- Pa_ReadStream and Pa_WriteStream.
-
- The standard formats paFloat32, paInt16, paInt32, paInt24, paInt8
- and aUInt8 are usually implemented by all implementations.
-
- The floating point representation (paFloat32) uses +1.0 and -1.0 as the
- maximum and minimum respectively.
-
- paUInt8 is an unsigned 8 bit format where 128 is considered "ground"
-
- The paNonInterleaved flag indicates that audio data is passed as an array
- of pointers to separate buffers, one buffer for each channel. Usually,
- when this flag is not used, audio data is passed as a single buffer with
- all channels interleaved.
-
- @see Pa_OpenStream, Pa_OpenDefaultStream, PaDeviceInfo
- @see paFloat32, paInt16, paInt32, paInt24, paInt8
- @see paUInt8, paCustomFormat, paNonInterleaved
-*/
-typedef unsigned long PaSampleFormat;
-
-
-#define paFloat32 ((PaSampleFormat) 0x00000001) /**< @see PaSampleFormat */
-#define paInt32 ((PaSampleFormat) 0x00000002) /**< @see PaSampleFormat */
-#define paInt24 ((PaSampleFormat) 0x00000004) /**< Packed 24 bit format. @see PaSampleFormat */
-#define paInt16 ((PaSampleFormat) 0x00000008) /**< @see PaSampleFormat */
-#define paInt8 ((PaSampleFormat) 0x00000010) /**< @see PaSampleFormat */
-#define paUInt8 ((PaSampleFormat) 0x00000020) /**< @see PaSampleFormat */
-#define paCustomFormat ((PaSampleFormat) 0x00010000) /**< @see PaSampleFormat */
-
-#define paNonInterleaved ((PaSampleFormat) 0x80000000) /**< @see PaSampleFormat */
-
-/** A structure providing information and capabilities of PortAudio devices.
- Devices may support input, output or both input and output.
-*/
-typedef struct PaDeviceInfo
-{
- int structVersion; /* this is struct version 2 */
- const char *name;
- PaHostApiIndex hostApi; /**< note this is a host API index, not a type id*/
-
- int maxInputChannels;
- int maxOutputChannels;
-
- /** Default latency values for interactive performance. */
- PaTime defaultLowInputLatency;
- PaTime defaultLowOutputLatency;
- /** Default latency values for robust non-interactive applications (eg. playing sound files). */
- PaTime defaultHighInputLatency;
- PaTime defaultHighOutputLatency;
-
- double defaultSampleRate;
-} PaDeviceInfo;
-
-
-/** Retrieve a pointer to a PaDeviceInfo structure containing information
- about the specified device.
- @return A pointer to an immutable PaDeviceInfo structure. If the device
- parameter is out of range the function returns NULL.
-
- @param device A valid device index in the range 0 to (Pa_GetDeviceCount()-1)
-
- @note PortAudio manages the memory referenced by the returned pointer,
- the client must not manipulate or free the memory. The pointer is only
- guaranteed to be valid between calls to Pa_Initialize() and Pa_Terminate().
-
- @see PaDeviceInfo, PaDeviceIndex
-*/
-const PaDeviceInfo* Pa_GetDeviceInfo( PaDeviceIndex device );
-
-
-/** Parameters for one direction (input or output) of a stream.
-*/
-typedef struct PaStreamParameters
-{
- /** A valid device index in the range 0 to (Pa_GetDeviceCount()-1)
- specifying the device to be used or the special constant
- paUseHostApiSpecificDeviceSpecification which indicates that the actual
- device(s) to use are specified in hostApiSpecificStreamInfo.
- This field must not be set to paNoDevice.
- */
- PaDeviceIndex device;
-
- /** The number of channels of sound to be delivered to the
- stream callback or accessed by Pa_ReadStream() or Pa_WriteStream().
- It can range from 1 to the value of maxInputChannels in the
- PaDeviceInfo record for the device specified by the device parameter.
- */
- int channelCount;
-
- /** The sample format of the buffer provided to the stream callback,
- a_ReadStream() or Pa_WriteStream(). It may be any of the formats described
- by the PaSampleFormat enumeration.
- */
- PaSampleFormat sampleFormat;
-
- /** The desired latency in seconds. Where practical, implementations should
- configure their latency based on these parameters, otherwise they may
- choose the closest viable latency instead. Unless the suggested latency
- is greater than the absolute upper limit for the device implementations
- should round the suggestedLatency up to the next practical value - ie to
- provide an equal or higher latency than suggestedLatency wherever possible.
- Actual latency values for an open stream may be retrieved using the
- inputLatency and outputLatency fields of the PaStreamInfo structure
- returned by Pa_GetStreamInfo().
- @see default*Latency in PaDeviceInfo, *Latency in PaStreamInfo
- */
- PaTime suggestedLatency;
-
- /** An optional pointer to a host api specific data structure
- containing additional information for device setup and/or stream processing.
- hostApiSpecificStreamInfo is never required for correct operation,
- if not used it should be set to NULL.
- */
- void *hostApiSpecificStreamInfo;
-
-} PaStreamParameters;
-
-
-/** Return code for Pa_IsFormatSupported indicating success. */
-#define paFormatIsSupported (0)
-
-/** Determine whether it would be possible to open a stream with the specified
- parameters.
-
- @param inputParameters A structure that describes the input parameters used to
- open a stream. The suggestedLatency field is ignored. See PaStreamParameters
- for a description of these parameters. inputParameters must be NULL for
- output-only streams.
-
- @param outputParameters A structure that describes the output parameters used
- to open a stream. The suggestedLatency field is ignored. See PaStreamParameters
- for a description of these parameters. outputParameters must be NULL for
- input-only streams.
-
- @param sampleRate The required sampleRate. For full-duplex streams it is the
- sample rate for both input and output
-
- @return Returns 0 if the format is supported, and an error code indicating why
- the format is not supported otherwise. The constant paFormatIsSupported is
- provided to compare with the return value for success.
-
- @see paFormatIsSupported, PaStreamParameters
-*/
-PaError Pa_IsFormatSupported( const PaStreamParameters *inputParameters,
- const PaStreamParameters *outputParameters,
- double sampleRate );
-
-
-
-/* Streaming types and functions */
-
-
-/**
- A single PaStream can provide multiple channels of real-time
- streaming audio input and output to a client application. A stream
- provides access to audio hardware represented by one or more
- PaDevices. Depending on the underlying Host API, it may be possible
- to open multiple streams using the same device, however this behavior
- is implementation defined. Portable applications should assume that
- a PaDevice may be simultaneously used by at most one PaStream.
-
- Pointers to PaStream objects are passed between PortAudio functions that
- operate on streams.
-
- @see Pa_OpenStream, Pa_OpenDefaultStream, Pa_OpenDefaultStream, Pa_CloseStream,
- Pa_StartStream, Pa_StopStream, Pa_AbortStream, Pa_IsStreamActive,
- Pa_GetStreamTime, Pa_GetStreamCpuLoad
-
-*/
-typedef void PaStream;
-
-
-/** Can be passed as the framesPerBuffer parameter to Pa_OpenStream()
- or Pa_OpenDefaultStream() to indicate that the stream callback will
- accept buffers of any size.
-*/
-#define paFramesPerBufferUnspecified (0)
-
-
-/** Flags used to control the behavior of a stream. They are passed as
- parameters to Pa_OpenStream or Pa_OpenDefaultStream. Multiple flags may be
- ORed together.
-
- @see Pa_OpenStream, Pa_OpenDefaultStream
- @see paNoFlag, paClipOff, paDitherOff, paNeverDropInput,
- paPrimeOutputBuffersUsingStreamCallback, paPlatformSpecificFlags
-*/
-typedef unsigned long PaStreamFlags;
-
-/** @see PaStreamFlags */
-#define paNoFlag ((PaStreamFlags) 0)
-
-/** Disable default clipping of out of range samples.
- @see PaStreamFlags
-*/
-#define paClipOff ((PaStreamFlags) 0x00000001)
-
-/** Disable default dithering.
- @see PaStreamFlags
-*/
-#define paDitherOff ((PaStreamFlags) 0x00000002)
-
-/** Flag requests that where possible a full duplex stream will not discard
- overflowed input samples without calling the stream callback. This flag is
- only valid for full duplex callback streams and only when used in combination
- with the paFramesPerBufferUnspecified (0) framesPerBuffer parameter. Using
- this flag incorrectly results in a paInvalidFlag error being returned from
- Pa_OpenStream and Pa_OpenDefaultStream.
-
- @see PaStreamFlags, paFramesPerBufferUnspecified
-*/
-#define paNeverDropInput ((PaStreamFlags) 0x00000004)
-
-/** Call the stream callback to fill initial output buffers, rather than the
- default behavior of priming the buffers with zeros (silence). This flag has
- no effect for input-only and blocking read/write streams.
-
- @see PaStreamFlags
-*/
-#define paPrimeOutputBuffersUsingStreamCallback ((PaStreamFlags) 0x00000008)
-
-/** A mask specifying the platform specific bits.
- @see PaStreamFlags
-*/
-#define paPlatformSpecificFlags ((PaStreamFlags)0xFFFF0000)
-
-/**
- Timing information for the buffers passed to the stream callback.
-
- Time values are expressed in seconds and are synchronised with the time base used by Pa_GetStreamTime() for the associated stream.
-
- @see PaStreamCallback, Pa_GetStreamTime
-*/
-typedef struct PaStreamCallbackTimeInfo{
- PaTime inputBufferAdcTime; /**< The time when the first sample of the input buffer was captured at the ADC input */
- PaTime currentTime; /**< The time when the stream callback was invoked */
- PaTime outputBufferDacTime; /**< The time when the first sample of the output buffer will output the DAC */
-} PaStreamCallbackTimeInfo;
-
-
-/**
- Flag bit constants for the statusFlags to PaStreamCallback.
-
- @see paInputUnderflow, paInputOverflow, paOutputUnderflow, paOutputOverflow,
- paPrimingOutput
-*/
-typedef unsigned long PaStreamCallbackFlags;
-
-/** In a stream opened with paFramesPerBufferUnspecified, indicates that
- input data is all silence (zeros) because no real data is available. In a
- stream opened without paFramesPerBufferUnspecified, it indicates that one or
- more zero samples have been inserted into the input buffer to compensate
- for an input underflow.
- @see PaStreamCallbackFlags
-*/
-#define paInputUnderflow ((PaStreamCallbackFlags) 0x00000001)
-
-/** In a stream opened with paFramesPerBufferUnspecified, indicates that data
- prior to the first sample of the input buffer was discarded due to an
- overflow, possibly because the stream callback is using too much CPU time.
- Otherwise indicates that data prior to one or more samples in the
- input buffer was discarded.
- @see PaStreamCallbackFlags
-*/
-#define paInputOverflow ((PaStreamCallbackFlags) 0x00000002)
-
-/** Indicates that output data (or a gap) was inserted, possibly because the
- stream callback is using too much CPU time.
- @see PaStreamCallbackFlags
-*/
-#define paOutputUnderflow ((PaStreamCallbackFlags) 0x00000004)
-
-/** Indicates that output data will be discarded because no room is available.
- @see PaStreamCallbackFlags
-*/
-#define paOutputOverflow ((PaStreamCallbackFlags) 0x00000008)
-
-/** Some of all of the output data will be used to prime the stream, input
- data may be zero.
- @see PaStreamCallbackFlags
-*/
-#define paPrimingOutput ((PaStreamCallbackFlags) 0x00000010)
-
-/**
- Allowable return values for the PaStreamCallback.
- @see PaStreamCallback
-*/
-typedef enum PaStreamCallbackResult
-{
- paContinue=0, /**< Signal that the stream should continue invoking the callback and processing audio. */
- paComplete=1, /**< Signal that the stream should stop invoking the callback and finish once all output samples have played. */
- paAbort=2 /**< Signal that the stream should stop invoking the callback and finish as soon as possible. */
-} PaStreamCallbackResult;
-
-
-/**
- Functions of type PaStreamCallback are implemented by PortAudio clients.
- They consume, process or generate audio in response to requests from an
- active PortAudio stream.
-
- When a stream is running, PortAudio calls the stream callback periodically.
- The callback function is responsible for processing buffers of audio samples
- passed via the input and output parameters.
-
- The PortAudio stream callback runs at very high or real-time priority.
- It is required to consistently meet its time deadlines. Do not allocate
- memory, access the file system, call library functions or call other functions
- from the stream callback that may block or take an unpredictable amount of
- time to complete.
-
- In order for a stream to maintain glitch-free operation the callback
- must consume and return audio data faster than it is recorded and/or
- played. PortAudio anticipates that each callback invocation may execute for
- a duration approaching the duration of frameCount audio frames at the stream
- sample rate. It is reasonable to expect to be able to utilise 70% or more of
- the available CPU time in the PortAudio callback. However, due to buffer size
- adaption and other factors, not all host APIs are able to guarantee audio
- stability under heavy CPU load with arbitrary fixed callback buffer sizes.
- When high callback CPU utilisation is required the most robust behavior
- can be achieved by using paFramesPerBufferUnspecified as the
- Pa_OpenStream() framesPerBuffer parameter.
-
- @param input and @param output are either arrays of interleaved samples or;
- if non-interleaved samples were requested using the paNonInterleaved sample
- format flag, an array of buffer pointers, one non-interleaved buffer for
- each channel.
-
- The format, packing and number of channels used by the buffers are
- determined by parameters to Pa_OpenStream().
-
- @param frameCount The number of sample frames to be processed by
- the stream callback.
-
- @param timeInfo Timestamps indicating the ADC capture time of the first sample
- in the input buffer, the DAC output time of the first sample in the output buffer
- and the time the callback was invoked.
- See PaStreamCallbackTimeInfo and Pa_GetStreamTime()
-
- @param statusFlags Flags indicating whether input and/or output buffers
- have been inserted or will be dropped to overcome underflow or overflow
- conditions.
-
- @param userData The value of a user supplied pointer passed to
- Pa_OpenStream() intended for storing synthesis data etc.
-
- @return
- The stream callback should return one of the values in the
- ::PaStreamCallbackResult enumeration. To ensure that the callback continues
- to be called, it should return paContinue (0). Either paComplete or paAbort
- can be returned to finish stream processing, after either of these values is
- returned the callback will not be called again. If paAbort is returned the
- stream will finish as soon as possible. If paComplete is returned, the stream
- will continue until all buffers generated by the callback have been played.
- This may be useful in applications such as soundfile players where a specific
- duration of output is required. However, it is not necessary to utilize this
- mechanism as Pa_StopStream(), Pa_AbortStream() or Pa_CloseStream() can also
- be used to stop the stream. The callback must always fill the entire output
- buffer irrespective of its return value.
-
- @see Pa_OpenStream, Pa_OpenDefaultStream
-
- @note With the exception of Pa_GetStreamCpuLoad() it is not permissible to call
- PortAudio API functions from within the stream callback.
-*/
-typedef int PaStreamCallback(
- const void *input, void *output,
- unsigned long frameCount,
- const PaStreamCallbackTimeInfo* timeInfo,
- PaStreamCallbackFlags statusFlags,
- void *userData );
-
-
-/** Opens a stream for either input, output or both.
-
- @param stream The address of a PaStream pointer which will receive
- a pointer to the newly opened stream.
-
- @param inputParameters A structure that describes the input parameters used by
- the opened stream. See PaStreamParameters for a description of these parameters.
- inputParameters must be NULL for output-only streams.
-
- @param outputParameters A structure that describes the output parameters used by
- the opened stream. See PaStreamParameters for a description of these parameters.
- outputParameters must be NULL for input-only streams.
-
- @param sampleRate The desired sampleRate. For full-duplex streams it is the
- sample rate for both input and output
-
- @param framesPerBuffer The number of frames passed to the stream callback
- function, or the preferred block granularity for a blocking read/write stream.
- The special value paFramesPerBufferUnspecified (0) may be used to request that
- the stream callback will receive an optimal (and possibly varying) number of
- frames based on host requirements and the requested latency settings.
- Note: With some host APIs, the use of non-zero framesPerBuffer for a callback
- stream may introduce an additional layer of buffering which could introduce
- additional latency. PortAudio guarantees that the additional latency
- will be kept to the theoretical minimum however, it is strongly recommended
- that a non-zero framesPerBuffer value only be used when your algorithm
- requires a fixed number of frames per stream callback.
-
- @param streamFlags Flags which modify the behavior of the streaming process.
- This parameter may contain a combination of flags ORed together. Some flags may
- only be relevant to certain buffer formats.
-
- @param streamCallback A pointer to a client supplied function that is responsible
- for processing and filling input and output buffers. If this parameter is NULL
- the stream will be opened in 'blocking read/write' mode. In blocking mode,
- the client can receive sample data using Pa_ReadStream and write sample data
- using Pa_WriteStream, the number of samples that may be read or written
- without blocking is returned by Pa_GetStreamReadAvailable and
- Pa_GetStreamWriteAvailable respectively.
-
- @param userData A client supplied pointer which is passed to the stream callback
- function. It could for example, contain a pointer to instance data necessary
- for processing the audio buffers. This parameter is ignored if streamCallback
- is NULL.
-
- @return
- Upon success Pa_OpenStream() returns paNoError and places a pointer to a
- valid PaStream in the stream argument. The stream is inactive (stopped).
- If a call to Pa_OpenStream() fails, a non-zero error code is returned (see
- PaError for possible error codes) and the value of stream is invalid.
-
- @see PaStreamParameters, PaStreamCallback, Pa_ReadStream, Pa_WriteStream,
- Pa_GetStreamReadAvailable, Pa_GetStreamWriteAvailable
-*/
-PaError Pa_OpenStream( PaStream** stream,
- const PaStreamParameters *inputParameters,
- const PaStreamParameters *outputParameters,
- double sampleRate,
- unsigned long framesPerBuffer,
- PaStreamFlags streamFlags,
- PaStreamCallback *streamCallback,
- void *userData );
-
-
-/** A simplified version of Pa_OpenStream() that opens the default input
- and/or output devices.
-
- @param stream The address of a PaStream pointer which will receive
- a pointer to the newly opened stream.
-
- @param numInputChannels The number of channels of sound that will be supplied
- to the stream callback or returned by Pa_ReadStream. It can range from 1 to
- the value of maxInputChannels in the PaDeviceInfo record for the default input
- device. If 0 the stream is opened as an output-only stream.
-
- @param numOutputChannels The number of channels of sound to be delivered to the
- stream callback or passed to Pa_WriteStream. It can range from 1 to the value
- of maxOutputChannels in the PaDeviceInfo record for the default output device.
- If 0 the stream is opened as an output-only stream.
-
- @param sampleFormat The sample format of both the input and output buffers
- provided to the callback or passed to and from Pa_ReadStream and Pa_WriteStream.
- sampleFormat may be any of the formats described by the PaSampleFormat
- enumeration.
-
- @param sampleRate Same as Pa_OpenStream parameter of the same name.
- @param framesPerBuffer Same as Pa_OpenStream parameter of the same name.
- @param streamCallback Same as Pa_OpenStream parameter of the same name.
- @param userData Same as Pa_OpenStream parameter of the same name.
-
- @return As for Pa_OpenStream
-
- @see Pa_OpenStream, PaStreamCallback
-*/
-PaError Pa_OpenDefaultStream( PaStream** stream,
- int numInputChannels,
- int numOutputChannels,
- PaSampleFormat sampleFormat,
- double sampleRate,
- unsigned long framesPerBuffer,
- PaStreamCallback *streamCallback,
- void *userData );
-
-
-/** Closes an audio stream. If the audio stream is active it
- discards any pending buffers as if Pa_AbortStream() had been called.
-*/
-PaError Pa_CloseStream( PaStream *stream );
-
-
-/** Functions of type PaStreamFinishedCallback are implemented by PortAudio
- clients. They can be registered with a stream using the Pa_SetStreamFinishedCallback
- function. Once registered they are called when the stream becomes inactive
- (ie once a call to Pa_StopStream() will not block).
- A stream will become inactive after the stream callback returns non-zero,
- or when Pa_StopStream or Pa_AbortStream is called. For a stream providing audio
- output, if the stream callback returns paComplete, or Pa_StopStream is called,
- the stream finished callback will not be called until all generated sample data
- has been played.
-
- @param userData The userData parameter supplied to Pa_OpenStream()
-
- @see Pa_SetStreamFinishedCallback
-*/
-typedef void PaStreamFinishedCallback( void *userData );
-
-
-/** Register a stream finished callback function which will be called when the
- stream becomes inactive. See the description of PaStreamFinishedCallback for
- further details about when the callback will be called.
-
- @param stream a pointer to a PaStream that is in the stopped state - if the
- stream is not stopped, the stream's finished callback will remain unchanged
- and an error code will be returned.
-
- @param streamFinishedCallback a pointer to a function with the same signature
- as PaStreamFinishedCallback, that will be called when the stream becomes
- inactive. Passing NULL for this parameter will un-register a previously
- registered stream finished callback function.
-
- @return on success returns paNoError, otherwise an error code indicating the cause
- of the error.
-
- @see PaStreamFinishedCallback
-*/
-PaError Pa_SetStreamFinishedCallback( PaStream *stream, PaStreamFinishedCallback* streamFinishedCallback );
-
-
-/** Commences audio processing.
-*/
-PaError Pa_StartStream( PaStream *stream );
-
-
-/** Terminates audio processing. It waits until all pending
- audio buffers have been played before it returns.
-*/
-PaError Pa_StopStream( PaStream *stream );
-
-
-/** Terminates audio processing immediately without waiting for pending
- buffers to complete.
-*/
-PaError Pa_AbortStream( PaStream *stream );
-
-
-/** Determine whether the stream is stopped.
- A stream is considered to be stopped prior to a successful call to
- Pa_StartStream and after a successful call to Pa_StopStream or Pa_AbortStream.
- If a stream callback returns a value other than paContinue the stream is NOT
- considered to be stopped.
-
- @return Returns one (1) when the stream is stopped, zero (0) when
- the stream is running or, a PaErrorCode (which are always negative) if
- PortAudio is not initialized or an error is encountered.
-
- @see Pa_StopStream, Pa_AbortStream, Pa_IsStreamActive
-*/
-PaError Pa_IsStreamStopped( PaStream *stream );
-
-
-/** Determine whether the stream is active.
- A stream is active after a successful call to Pa_StartStream(), until it
- becomes inactive either as a result of a call to Pa_StopStream() or
- Pa_AbortStream(), or as a result of a return value other than paContinue from
- the stream callback. In the latter case, the stream is considered inactive
- after the last buffer has finished playing.
-
- @return Returns one (1) when the stream is active (ie playing or recording
- audio), zero (0) when not playing or, a PaErrorCode (which are always negative)
- if PortAudio is not initialized or an error is encountered.
-
- @see Pa_StopStream, Pa_AbortStream, Pa_IsStreamStopped
-*/
-PaError Pa_IsStreamActive( PaStream *stream );
-
-
-
-/** A structure containing unchanging information about an open stream.
- @see Pa_GetStreamInfo
-*/
-
-typedef struct PaStreamInfo
-{
- /** this is struct version 1 */
- int structVersion;
-
- /** The input latency of the stream in seconds. This value provides the most
- accurate estimate of input latency available to the implementation. It may
- differ significantly from the suggestedLatency value passed to Pa_OpenStream().
- The value of this field will be zero (0.) for output-only streams.
- @see PaTime
- */
- PaTime inputLatency;
-
- /** The output latency of the stream in seconds. This value provides the most
- accurate estimate of output latency available to the implementation. It may
- differ significantly from the suggestedLatency value passed to Pa_OpenStream().
- The value of this field will be zero (0.) for input-only streams.
- @see PaTime
- */
- PaTime outputLatency;
-
- /** The sample rate of the stream in Hertz (samples per second). In cases
- where the hardware sample rate is inaccurate and PortAudio is aware of it,
- the value of this field may be different from the sampleRate parameter
- passed to Pa_OpenStream(). If information about the actual hardware sample
- rate is not available, this field will have the same value as the sampleRate
- parameter passed to Pa_OpenStream().
- */
- double sampleRate;
-
-} PaStreamInfo;
-
-
-/** Retrieve a pointer to a PaStreamInfo structure containing information
- about the specified stream.
- @return A pointer to an immutable PaStreamInfo structure. If the stream
- parameter invalid, or an error is encountered, the function returns NULL.
-
- @param stream A pointer to an open stream previously created with Pa_OpenStream.
-
- @note PortAudio manages the memory referenced by the returned pointer,
- the client must not manipulate or free the memory. The pointer is only
- guaranteed to be valid until the specified stream is closed.
-
- @see PaStreamInfo
-*/
-const PaStreamInfo* Pa_GetStreamInfo( PaStream *stream );
-
-
-/** Returns the current time in seconds for a stream according to the same clock used
- to generate callback PaStreamCallbackTimeInfo timestamps. The time values are
- monotonically increasing and have unspecified origin.
-
- Pa_GetStreamTime returns valid time values for the entire life of the stream,
- from when the stream is opened until it is closed. Starting and stopping the stream
- does not affect the passage of time returned by Pa_GetStreamTime.
-
- This time may be used for synchronizing other events to the audio stream, for
- example synchronizing audio to MIDI.
-
- @return The stream's current time in seconds, or 0 if an error occurred.
-
- @see PaTime, PaStreamCallback, PaStreamCallbackTimeInfo
-*/
-PaTime Pa_GetStreamTime( PaStream *stream );
-
-
-/** Retrieve CPU usage information for the specified stream.
- The "CPU Load" is a fraction of total CPU time consumed by a callback stream's
- audio processing routines including, but not limited to the client supplied
- stream callback. This function does not work with blocking read/write streams.
-
- This function may be called from the stream callback function or the
- application.
-
- @return
- A floating point value, typically between 0.0 and 1.0, where 1.0 indicates
- that the stream callback is consuming the maximum number of CPU cycles possible
- to maintain real-time operation. A value of 0.5 would imply that PortAudio and
- the stream callback was consuming roughly 50% of the available CPU time. The
- return value may exceed 1.0. A value of 0.0 will always be returned for a
- blocking read/write stream, or if an error occurs.
-*/
-double Pa_GetStreamCpuLoad( PaStream* stream );
-
-
-/** Read samples from an input stream. The function doesn't return until
- the entire buffer has been filled - this may involve waiting for the operating
- system to supply the data.
-
- @param stream A pointer to an open stream previously created with Pa_OpenStream.
-
- @param buffer A pointer to a buffer of sample frames. The buffer contains
- samples in the format specified by the inputParameters->sampleFormat field
- used to open the stream, and the number of channels specified by
- inputParameters->numChannels. If non-interleaved samples were requested using
- the paNonInterleaved sample format flag, buffer is a pointer to the first element
- of an array of buffer pointers, one non-interleaved buffer for each channel.
-
- @param frames The number of frames to be read into buffer. This parameter
- is not constrained to a specific range, however high performance applications
- will want to match this parameter to the framesPerBuffer parameter used
- when opening the stream.
-
- @return On success PaNoError will be returned, or PaInputOverflowed if input
- data was discarded by PortAudio after the previous call and before this call.
-*/
-PaError Pa_ReadStream( PaStream* stream,
- void *buffer,
- unsigned long frames );
-
-
-/** Write samples to an output stream. This function doesn't return until the
- entire buffer has been consumed - this may involve waiting for the operating
- system to consume the data.
-
- @param stream A pointer to an open stream previously created with Pa_OpenStream.
-
- @param buffer A pointer to a buffer of sample frames. The buffer contains
- samples in the format specified by the outputParameters->sampleFormat field
- used to open the stream, and the number of channels specified by
- outputParameters->numChannels. If non-interleaved samples were requested using
- the paNonInterleaved sample format flag, buffer is a pointer to the first element
- of an array of buffer pointers, one non-interleaved buffer for each channel.
-
- @param frames The number of frames to be written from buffer. This parameter
- is not constrained to a specific range, however high performance applications
- will want to match this parameter to the framesPerBuffer parameter used
- when opening the stream.
-
- @return On success PaNoError will be returned, or paOutputUnderflowed if
- additional output data was inserted after the previous call and before this
- call.
-*/
-PaError Pa_WriteStream( PaStream* stream,
- const void *buffer,
- unsigned long frames );
-
-
-/** Retrieve the number of frames that can be read from the stream without
- waiting.
-
- @return Returns a non-negative value representing the maximum number of frames
- that can be read from the stream without blocking or busy waiting or, a
- PaErrorCode (which are always negative) if PortAudio is not initialized or an
- error is encountered.
-*/
-signed long Pa_GetStreamReadAvailable( PaStream* stream );
-
-
-/** Retrieve the number of frames that can be written to the stream without
- waiting.
-
- @return Returns a non-negative value representing the maximum number of frames
- that can be written to the stream without blocking or busy waiting or, a
- PaErrorCode (which are always negative) if PortAudio is not initialized or an
- error is encountered.
-*/
-signed long Pa_GetStreamWriteAvailable( PaStream* stream );
-
-
-/* Miscellaneous utilities */
-
-
-/** Retrieve the size of a given sample format in bytes.
-
- @return The size in bytes of a single sample in the specified format,
- or paSampleFormatNotSupported if the format is not supported.
-*/
-PaError Pa_GetSampleSize( PaSampleFormat format );
-
-
-/** Put the caller to sleep for at least 'msec' milliseconds. This function is
- provided only as a convenience for authors of portable code (such as the tests
- and examples in the PortAudio distribution.)
-
- The function may sleep longer than requested so don't rely on this for accurate
- musical timing.
-*/
-void Pa_Sleep( long msec );
-
-
-
-#ifdef __cplusplus
-}
-#endif /* __cplusplus */
-#endif /* PORTAUDIO_H */
+#ifndef PORTAUDIO_H\r
+#define PORTAUDIO_H\r
+/*\r
+ * $Id: portaudio.h 1745 2011-08-25 17:44:01Z rossb $\r
+ * PortAudio Portable Real-Time Audio Library\r
+ * PortAudio API Header File\r
+ * Latest version available at: http://www.portaudio.com/\r
+ *\r
+ * Copyright (c) 1999-2002 Ross Bencina and Phil Burk\r
+ *\r
+ * Permission is hereby granted, free of charge, to any person obtaining\r
+ * a copy of this software and associated documentation files\r
+ * (the "Software"), to deal in the Software without restriction,\r
+ * including without limitation the rights to use, copy, modify, merge,\r
+ * publish, distribute, sublicense, and/or sell copies of the Software,\r
+ * and to permit persons to whom the Software is furnished to do so,\r
+ * subject to the following conditions:\r
+ *\r
+ * The above copyright notice and this permission notice shall be\r
+ * included in all copies or substantial portions of the Software.\r
+ *\r
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,\r
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF\r
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.\r
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR\r
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF\r
+ * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION\r
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.\r
+ */\r
+\r
+/*\r
+ * The text above constitutes the entire PortAudio license; however, \r
+ * the PortAudio community also makes the following non-binding requests:\r
+ *\r
+ * Any person wishing to distribute modifications to the Software is\r
+ * requested to send the modifications to the original developer so that\r
+ * they can be incorporated into the canonical version. It is also \r
+ * requested that these non-binding requests be included along with the \r
+ * license above.\r
+ */\r
+\r
+/** @file\r
+ @ingroup public_header\r
+ @brief The portable PortAudio API.\r
+*/\r
+\r
+\r
+#ifdef __cplusplus\r
+extern "C"\r
+{\r
+#endif /* __cplusplus */\r
+\r
+ \r
+/** Retrieve the release number of the currently running PortAudio build,\r
+ eg 1900.\r
+*/\r
+int Pa_GetVersion( void );\r
+\r
+\r
+/** Retrieve a textual description of the current PortAudio build,\r
+ eg "PortAudio V19-devel 13 October 2002".\r
+*/\r
+const char* Pa_GetVersionText( void );\r
+\r
+\r
+/** Error codes returned by PortAudio functions.\r
+ Note that with the exception of paNoError, all PaErrorCodes are negative.\r
+*/\r
+\r
+typedef int PaError;\r
+typedef enum PaErrorCode\r
+{\r
+ paNoError = 0,\r
+\r
+ paNotInitialized = -10000,\r
+ paUnanticipatedHostError,\r
+ paInvalidChannelCount,\r
+ paInvalidSampleRate,\r
+ paInvalidDevice,\r
+ paInvalidFlag,\r
+ paSampleFormatNotSupported,\r
+ paBadIODeviceCombination,\r
+ paInsufficientMemory,\r
+ paBufferTooBig,\r
+ paBufferTooSmall,\r
+ paNullCallback,\r
+ paBadStreamPtr,\r
+ paTimedOut,\r
+ paInternalError,\r
+ paDeviceUnavailable,\r
+ paIncompatibleHostApiSpecificStreamInfo,\r
+ paStreamIsStopped,\r
+ paStreamIsNotStopped,\r
+ paInputOverflowed,\r
+ paOutputUnderflowed,\r
+ paHostApiNotFound,\r
+ paInvalidHostApi,\r
+ paCanNotReadFromACallbackStream,\r
+ paCanNotWriteToACallbackStream,\r
+ paCanNotReadFromAnOutputOnlyStream,\r
+ paCanNotWriteToAnInputOnlyStream,\r
+ paIncompatibleStreamHostApi,\r
+ paBadBufferPtr\r
+} PaErrorCode;\r
+\r
+\r
+/** Translate the supplied PortAudio error code into a human readable\r
+ message.\r
+*/\r
+const char *Pa_GetErrorText( PaError errorCode );\r
+\r
+\r
+/** Library initialization function - call this before using PortAudio.\r
+ This function initializes internal data structures and prepares underlying\r
+ host APIs for use. With the exception of Pa_GetVersion(), Pa_GetVersionText(),\r
+ and Pa_GetErrorText(), this function MUST be called before using any other\r
+ PortAudio API functions.\r
+\r
+ If Pa_Initialize() is called multiple times, each successful \r
+ call must be matched with a corresponding call to Pa_Terminate(). \r
+ Pairs of calls to Pa_Initialize()/Pa_Terminate() may overlap, and are not \r
+ required to be fully nested.\r
+\r
+ Note that if Pa_Initialize() returns an error code, Pa_Terminate() should\r
+ NOT be called.\r
+\r
+ @return paNoError if successful, otherwise an error code indicating the cause\r
+ of failure.\r
+\r
+ @see Pa_Terminate\r
+*/\r
+PaError Pa_Initialize( void );\r
+\r
+\r
+/** Library termination function - call this when finished using PortAudio.\r
+ This function deallocates all resources allocated by PortAudio since it was\r
+ initialized by a call to Pa_Initialize(). In cases where Pa_Initialise() has\r
+ been called multiple times, each call must be matched with a corresponding call\r
+ to Pa_Terminate(). The final matching call to Pa_Terminate() will automatically\r
+ close any PortAudio streams that are still open.\r
+\r
+ Pa_Terminate() MUST be called before exiting a program which uses PortAudio.\r
+ Failure to do so may result in serious resource leaks, such as audio devices\r
+ not being available until the next reboot.\r
+\r
+ @return paNoError if successful, otherwise an error code indicating the cause\r
+ of failure.\r
+ \r
+ @see Pa_Initialize\r
+*/\r
+PaError Pa_Terminate( void );\r
+\r
+\r
+\r
+/** The type used to refer to audio devices. Values of this type usually\r
+ range from 0 to (Pa_GetDeviceCount()-1), and may also take on the PaNoDevice\r
+ and paUseHostApiSpecificDeviceSpecification values.\r
+\r
+ @see Pa_GetDeviceCount, paNoDevice, paUseHostApiSpecificDeviceSpecification\r
+*/\r
+typedef int PaDeviceIndex;\r
+\r
+\r
+/** A special PaDeviceIndex value indicating that no device is available,\r
+ or should be used.\r
+\r
+ @see PaDeviceIndex\r
+*/\r
+#define paNoDevice ((PaDeviceIndex)-1)\r
+\r
+\r
+/** A special PaDeviceIndex value indicating that the device(s) to be used\r
+ are specified in the host api specific stream info structure.\r
+\r
+ @see PaDeviceIndex\r
+*/\r
+#define paUseHostApiSpecificDeviceSpecification ((PaDeviceIndex)-2)\r
+\r
+\r
+/* Host API enumeration mechanism */\r
+\r
+/** The type used to enumerate to host APIs at runtime. Values of this type\r
+ range from 0 to (Pa_GetHostApiCount()-1).\r
+\r
+ @see Pa_GetHostApiCount\r
+*/\r
+typedef int PaHostApiIndex;\r
+\r
+\r
+/** Retrieve the number of available host APIs. Even if a host API is\r
+ available it may have no devices available.\r
+\r
+ @return A non-negative value indicating the number of available host APIs\r
+ or, a PaErrorCode (which are always negative) if PortAudio is not initialized\r
+ or an error is encountered.\r
+\r
+ @see PaHostApiIndex\r
+*/\r
+PaHostApiIndex Pa_GetHostApiCount( void );\r
+\r
+\r
+/** Retrieve the index of the default host API. The default host API will be\r
+ the lowest common denominator host API on the current platform and is\r
+ unlikely to provide the best performance.\r
+\r
+ @return A non-negative value ranging from 0 to (Pa_GetHostApiCount()-1)\r
+ indicating the default host API index or, a PaErrorCode (which are always\r
+ negative) if PortAudio is not initialized or an error is encountered.\r
+*/\r
+PaHostApiIndex Pa_GetDefaultHostApi( void );\r
+\r
+\r
+/** Unchanging unique identifiers for each supported host API. This type\r
+ is used in the PaHostApiInfo structure. The values are guaranteed to be\r
+ unique and to never change, thus allowing code to be written that\r
+ conditionally uses host API specific extensions.\r
+\r
+ New type ids will be allocated when support for a host API reaches\r
+ "public alpha" status, prior to that developers should use the\r
+ paInDevelopment type id.\r
+\r
+ @see PaHostApiInfo\r
+*/\r
+typedef enum PaHostApiTypeId\r
+{\r
+ paInDevelopment=0, /* use while developing support for a new host API */\r
+ paDirectSound=1,\r
+ paMME=2,\r
+ paASIO=3,\r
+ paSoundManager=4,\r
+ paCoreAudio=5,\r
+ paOSS=7,\r
+ paALSA=8,\r
+ paAL=9,\r
+ paBeOS=10,\r
+ paWDMKS=11,\r
+ paJACK=12,\r
+ paWASAPI=13,\r
+ paAudioScienceHPI=14\r
+} PaHostApiTypeId;\r
+\r
+\r
+/** A structure containing information about a particular host API. */\r
+\r
+typedef struct PaHostApiInfo\r
+{\r
+ /** this is struct version 1 */\r
+ int structVersion;\r
+ /** The well known unique identifier of this host API @see PaHostApiTypeId */\r
+ PaHostApiTypeId type;\r
+ /** A textual description of the host API for display on user interfaces. */\r
+ const char *name;\r
+\r
+ /** The number of devices belonging to this host API. This field may be\r
+ used in conjunction with Pa_HostApiDeviceIndexToDeviceIndex() to enumerate\r
+ all devices for this host API.\r
+ @see Pa_HostApiDeviceIndexToDeviceIndex\r
+ */\r
+ int deviceCount;\r
+\r
+ /** The default input device for this host API. The value will be a\r
+ device index ranging from 0 to (Pa_GetDeviceCount()-1), or paNoDevice\r
+ if no default input device is available.\r
+ */\r
+ PaDeviceIndex defaultInputDevice;\r
+\r
+ /** The default output device for this host API. The value will be a\r
+ device index ranging from 0 to (Pa_GetDeviceCount()-1), or paNoDevice\r
+ if no default output device is available.\r
+ */\r
+ PaDeviceIndex defaultOutputDevice;\r
+ \r
+} PaHostApiInfo;\r
+\r
+\r
+/** Retrieve a pointer to a structure containing information about a specific\r
+ host Api.\r
+\r
+ @param hostApi A valid host API index ranging from 0 to (Pa_GetHostApiCount()-1)\r
+\r
+ @return A pointer to an immutable PaHostApiInfo structure describing\r
+ a specific host API. If the hostApi parameter is out of range or an error\r
+ is encountered, the function returns NULL.\r
+\r
+ The returned structure is owned by the PortAudio implementation and must not\r
+ be manipulated or freed. The pointer is only guaranteed to be valid between\r
+ calls to Pa_Initialize() and Pa_Terminate().\r
+*/\r
+const PaHostApiInfo * Pa_GetHostApiInfo( PaHostApiIndex hostApi );\r
+\r
+\r
+/** Convert a static host API unique identifier, into a runtime\r
+ host API index.\r
+\r
+ @param type A unique host API identifier belonging to the PaHostApiTypeId\r
+ enumeration.\r
+\r
+ @return A valid PaHostApiIndex ranging from 0 to (Pa_GetHostApiCount()-1) or,\r
+ a PaErrorCode (which are always negative) if PortAudio is not initialized\r
+ or an error is encountered.\r
+ \r
+ The paHostApiNotFound error code indicates that the host API specified by the\r
+ type parameter is not available.\r
+\r
+ @see PaHostApiTypeId\r
+*/\r
+PaHostApiIndex Pa_HostApiTypeIdToHostApiIndex( PaHostApiTypeId type );\r
+\r
+\r
+/** Convert a host-API-specific device index to standard PortAudio device index.\r
+ This function may be used in conjunction with the deviceCount field of\r
+ PaHostApiInfo to enumerate all devices for the specified host API.\r
+\r
+ @param hostApi A valid host API index ranging from 0 to (Pa_GetHostApiCount()-1)\r
+\r
+ @param hostApiDeviceIndex A valid per-host device index in the range\r
+ 0 to (Pa_GetHostApiInfo(hostApi)->deviceCount-1)\r
+\r
+ @return A non-negative PaDeviceIndex ranging from 0 to (Pa_GetDeviceCount()-1)\r
+ or, a PaErrorCode (which are always negative) if PortAudio is not initialized\r
+ or an error is encountered.\r
+\r
+ A paInvalidHostApi error code indicates that the host API index specified by\r
+ the hostApi parameter is out of range.\r
+\r
+ A paInvalidDevice error code indicates that the hostApiDeviceIndex parameter\r
+ is out of range.\r
+ \r
+ @see PaHostApiInfo\r
+*/\r
+PaDeviceIndex Pa_HostApiDeviceIndexToDeviceIndex( PaHostApiIndex hostApi,\r
+ int hostApiDeviceIndex );\r
+\r
+\r
+\r
+/** Structure used to return information about a host error condition.\r
+*/\r
+typedef struct PaHostErrorInfo{\r
+ PaHostApiTypeId hostApiType; /**< the host API which returned the error code */\r
+ long errorCode; /**< the error code returned */\r
+ const char *errorText; /**< a textual description of the error if available, otherwise a zero-length string */\r
+}PaHostErrorInfo;\r
+\r
+\r
+/** Return information about the last host error encountered. The error\r
+ information returned by Pa_GetLastHostErrorInfo() will never be modified\r
+ asynchronously by errors occurring in other PortAudio owned threads\r
+ (such as the thread that manages the stream callback.)\r
+\r
+ This function is provided as a last resort, primarily to enhance debugging\r
+ by providing clients with access to all available error information.\r
+\r
+ @return A pointer to an immutable structure constraining information about\r
+ the host error. The values in this structure will only be valid if a\r
+ PortAudio function has previously returned the paUnanticipatedHostError\r
+ error code.\r
+*/\r
+const PaHostErrorInfo* Pa_GetLastHostErrorInfo( void );\r
+\r
+\r
+\r
+/* Device enumeration and capabilities */\r
+\r
+/** Retrieve the number of available devices. The number of available devices\r
+ may be zero.\r
+\r
+ @return A non-negative value indicating the number of available devices or,\r
+ a PaErrorCode (which are always negative) if PortAudio is not initialized\r
+ or an error is encountered.\r
+*/\r
+PaDeviceIndex Pa_GetDeviceCount( void );\r
+\r
+\r
+/** Retrieve the index of the default input device. The result can be\r
+ used in the inputDevice parameter to Pa_OpenStream().\r
+\r
+ @return The default input device index for the default host API, or paNoDevice\r
+ if no default input device is available or an error was encountered.\r
+*/\r
+PaDeviceIndex Pa_GetDefaultInputDevice( void );\r
+\r
+\r
+/** Retrieve the index of the default output device. The result can be\r
+ used in the outputDevice parameter to Pa_OpenStream().\r
+\r
+ @return The default output device index for the default host API, or paNoDevice\r
+ if no default output device is available or an error was encountered.\r
+\r
+ @note\r
+ On the PC, the user can specify a default device by\r
+ setting an environment variable. For example, to use device #1.\r
+<pre>\r
+ set PA_RECOMMENDED_OUTPUT_DEVICE=1\r
+</pre>\r
+ The user should first determine the available device ids by using\r
+ the supplied application "pa_devs".\r
+*/\r
+PaDeviceIndex Pa_GetDefaultOutputDevice( void );\r
+\r
+\r
+/** The type used to represent monotonic time in seconds. PaTime is \r
+ used for the fields of the PaStreamCallbackTimeInfo argument to the \r
+ PaStreamCallback and as the result of Pa_GetStreamTime().\r
+\r
+ PaTime values have unspecified origin.\r
+ \r
+ @see PaStreamCallback, PaStreamCallbackTimeInfo, Pa_GetStreamTime\r
+*/\r
+typedef double PaTime;\r
+\r
+\r
+/** A type used to specify one or more sample formats. Each value indicates\r
+ a possible format for sound data passed to and from the stream callback,\r
+ Pa_ReadStream and Pa_WriteStream.\r
+\r
+ The standard formats paFloat32, paInt16, paInt32, paInt24, paInt8\r
+ and aUInt8 are usually implemented by all implementations.\r
+\r
+ The floating point representation (paFloat32) uses +1.0 and -1.0 as the\r
+ maximum and minimum respectively.\r
+\r
+ paUInt8 is an unsigned 8 bit format where 128 is considered "ground"\r
+\r
+ The paNonInterleaved flag indicates that audio data is passed as an array \r
+ of pointers to separate buffers, one buffer for each channel. Usually,\r
+ when this flag is not used, audio data is passed as a single buffer with\r
+ all channels interleaved.\r
+\r
+ @see Pa_OpenStream, Pa_OpenDefaultStream, PaDeviceInfo\r
+ @see paFloat32, paInt16, paInt32, paInt24, paInt8\r
+ @see paUInt8, paCustomFormat, paNonInterleaved\r
+*/\r
+typedef unsigned long PaSampleFormat;\r
+\r
+\r
+#define paFloat32 ((PaSampleFormat) 0x00000001) /**< @see PaSampleFormat */\r
+#define paInt32 ((PaSampleFormat) 0x00000002) /**< @see PaSampleFormat */\r
+#define paInt24 ((PaSampleFormat) 0x00000004) /**< Packed 24 bit format. @see PaSampleFormat */\r
+#define paInt16 ((PaSampleFormat) 0x00000008) /**< @see PaSampleFormat */\r
+#define paInt8 ((PaSampleFormat) 0x00000010) /**< @see PaSampleFormat */\r
+#define paUInt8 ((PaSampleFormat) 0x00000020) /**< @see PaSampleFormat */\r
+#define paCustomFormat ((PaSampleFormat) 0x00010000) /**< @see PaSampleFormat */\r
+\r
+#define paNonInterleaved ((PaSampleFormat) 0x80000000) /**< @see PaSampleFormat */\r
+\r
+/** A structure providing information and capabilities of PortAudio devices.\r
+ Devices may support input, output or both input and output.\r
+*/\r
+typedef struct PaDeviceInfo\r
+{\r
+ int structVersion; /* this is struct version 2 */\r
+ const char *name;\r
+ PaHostApiIndex hostApi; /**< note this is a host API index, not a type id*/\r
+ \r
+ int maxInputChannels;\r
+ int maxOutputChannels;\r
+\r
+ /** Default latency values for interactive performance. */\r
+ PaTime defaultLowInputLatency;\r
+ PaTime defaultLowOutputLatency;\r
+ /** Default latency values for robust non-interactive applications (eg. playing sound files). */\r
+ PaTime defaultHighInputLatency;\r
+ PaTime defaultHighOutputLatency;\r
+\r
+ double defaultSampleRate;\r
+} PaDeviceInfo;\r
+\r
+\r
+/** Retrieve a pointer to a PaDeviceInfo structure containing information\r
+ about the specified device.\r
+ @return A pointer to an immutable PaDeviceInfo structure. If the device\r
+ parameter is out of range the function returns NULL.\r
+\r
+ @param device A valid device index in the range 0 to (Pa_GetDeviceCount()-1)\r
+\r
+ @note PortAudio manages the memory referenced by the returned pointer,\r
+ the client must not manipulate or free the memory. The pointer is only\r
+ guaranteed to be valid between calls to Pa_Initialize() and Pa_Terminate().\r
+\r
+ @see PaDeviceInfo, PaDeviceIndex\r
+*/\r
+const PaDeviceInfo* Pa_GetDeviceInfo( PaDeviceIndex device );\r
+\r
+\r
+/** Parameters for one direction (input or output) of a stream.\r
+*/\r
+typedef struct PaStreamParameters\r
+{\r
+ /** A valid device index in the range 0 to (Pa_GetDeviceCount()-1)\r
+ specifying the device to be used or the special constant\r
+ paUseHostApiSpecificDeviceSpecification which indicates that the actual\r
+ device(s) to use are specified in hostApiSpecificStreamInfo.\r
+ This field must not be set to paNoDevice.\r
+ */\r
+ PaDeviceIndex device;\r
+ \r
+ /** The number of channels of sound to be delivered to the\r
+ stream callback or accessed by Pa_ReadStream() or Pa_WriteStream().\r
+ It can range from 1 to the value of maxInputChannels in the\r
+ PaDeviceInfo record for the device specified by the device parameter.\r
+ */\r
+ int channelCount;\r
+\r
+ /** The sample format of the buffer provided to the stream callback,\r
+ a_ReadStream() or Pa_WriteStream(). It may be any of the formats described\r
+ by the PaSampleFormat enumeration.\r
+ */\r
+ PaSampleFormat sampleFormat;\r
+\r
+ /** The desired latency in seconds. Where practical, implementations should\r
+ configure their latency based on these parameters, otherwise they may\r
+ choose the closest viable latency instead. Unless the suggested latency\r
+ is greater than the absolute upper limit for the device implementations\r
+ should round the suggestedLatency up to the next practical value - ie to\r
+ provide an equal or higher latency than suggestedLatency wherever possible.\r
+ Actual latency values for an open stream may be retrieved using the\r
+ inputLatency and outputLatency fields of the PaStreamInfo structure\r
+ returned by Pa_GetStreamInfo().\r
+ @see default*Latency in PaDeviceInfo, *Latency in PaStreamInfo\r
+ */\r
+ PaTime suggestedLatency;\r
+\r
+ /** An optional pointer to a host api specific data structure\r
+ containing additional information for device setup and/or stream processing.\r
+ hostApiSpecificStreamInfo is never required for correct operation,\r
+ if not used it should be set to NULL.\r
+ */\r
+ void *hostApiSpecificStreamInfo;\r
+\r
+} PaStreamParameters;\r
+\r
+\r
+/** Return code for Pa_IsFormatSupported indicating success. */\r
+#define paFormatIsSupported (0)\r
+\r
+/** Determine whether it would be possible to open a stream with the specified\r
+ parameters.\r
+\r
+ @param inputParameters A structure that describes the input parameters used to\r
+ open a stream. The suggestedLatency field is ignored. See PaStreamParameters\r
+ for a description of these parameters. inputParameters must be NULL for\r
+ output-only streams.\r
+\r
+ @param outputParameters A structure that describes the output parameters used\r
+ to open a stream. The suggestedLatency field is ignored. See PaStreamParameters\r
+ for a description of these parameters. outputParameters must be NULL for\r
+ input-only streams.\r
+\r
+ @param sampleRate The required sampleRate. For full-duplex streams it is the\r
+ sample rate for both input and output\r
+\r
+ @return Returns 0 if the format is supported, and an error code indicating why\r
+ the format is not supported otherwise. The constant paFormatIsSupported is\r
+ provided to compare with the return value for success.\r
+\r
+ @see paFormatIsSupported, PaStreamParameters\r
+*/\r
+PaError Pa_IsFormatSupported( const PaStreamParameters *inputParameters,\r
+ const PaStreamParameters *outputParameters,\r
+ double sampleRate );\r
+\r
+\r
+\r
+/* Streaming types and functions */\r
+\r
+\r
+/**\r
+ A single PaStream can provide multiple channels of real-time\r
+ streaming audio input and output to a client application. A stream\r
+ provides access to audio hardware represented by one or more\r
+ PaDevices. Depending on the underlying Host API, it may be possible \r
+ to open multiple streams using the same device, however this behavior \r
+ is implementation defined. Portable applications should assume that \r
+ a PaDevice may be simultaneously used by at most one PaStream.\r
+\r
+ Pointers to PaStream objects are passed between PortAudio functions that\r
+ operate on streams.\r
+\r
+ @see Pa_OpenStream, Pa_OpenDefaultStream, Pa_OpenDefaultStream, Pa_CloseStream,\r
+ Pa_StartStream, Pa_StopStream, Pa_AbortStream, Pa_IsStreamActive,\r
+ Pa_GetStreamTime, Pa_GetStreamCpuLoad\r
+\r
+*/\r
+typedef void PaStream;\r
+\r
+\r
+/** Can be passed as the framesPerBuffer parameter to Pa_OpenStream()\r
+ or Pa_OpenDefaultStream() to indicate that the stream callback will\r
+ accept buffers of any size.\r
+*/\r
+#define paFramesPerBufferUnspecified (0)\r
+\r
+\r
+/** Flags used to control the behavior of a stream. They are passed as\r
+ parameters to Pa_OpenStream or Pa_OpenDefaultStream. Multiple flags may be\r
+ ORed together.\r
+\r
+ @see Pa_OpenStream, Pa_OpenDefaultStream\r
+ @see paNoFlag, paClipOff, paDitherOff, paNeverDropInput,\r
+ paPrimeOutputBuffersUsingStreamCallback, paPlatformSpecificFlags\r
+*/\r
+typedef unsigned long PaStreamFlags;\r
+\r
+/** @see PaStreamFlags */\r
+#define paNoFlag ((PaStreamFlags) 0)\r
+\r
+/** Disable default clipping of out of range samples.\r
+ @see PaStreamFlags\r
+*/\r
+#define paClipOff ((PaStreamFlags) 0x00000001)\r
+\r
+/** Disable default dithering.\r
+ @see PaStreamFlags\r
+*/\r
+#define paDitherOff ((PaStreamFlags) 0x00000002)\r
+\r
+/** Flag requests that where possible a full duplex stream will not discard\r
+ overflowed input samples without calling the stream callback. This flag is\r
+ only valid for full duplex callback streams and only when used in combination\r
+ with the paFramesPerBufferUnspecified (0) framesPerBuffer parameter. Using\r
+ this flag incorrectly results in a paInvalidFlag error being returned from\r
+ Pa_OpenStream and Pa_OpenDefaultStream.\r
+\r
+ @see PaStreamFlags, paFramesPerBufferUnspecified\r
+*/\r
+#define paNeverDropInput ((PaStreamFlags) 0x00000004)\r
+\r
+/** Call the stream callback to fill initial output buffers, rather than the\r
+ default behavior of priming the buffers with zeros (silence). This flag has\r
+ no effect for input-only and blocking read/write streams.\r
+ \r
+ @see PaStreamFlags\r
+*/\r
+#define paPrimeOutputBuffersUsingStreamCallback ((PaStreamFlags) 0x00000008)\r
+\r
+/** A mask specifying the platform specific bits.\r
+ @see PaStreamFlags\r
+*/\r
+#define paPlatformSpecificFlags ((PaStreamFlags)0xFFFF0000)\r
+\r
+/**\r
+ Timing information for the buffers passed to the stream callback.\r
+\r
+ Time values are expressed in seconds and are synchronised with the time base used by Pa_GetStreamTime() for the associated stream.\r
+ \r
+ @see PaStreamCallback, Pa_GetStreamTime\r
+*/\r
+typedef struct PaStreamCallbackTimeInfo{\r
+ PaTime inputBufferAdcTime; /**< The time when the first sample of the input buffer was captured at the ADC input */\r
+ PaTime currentTime; /**< The time when the stream callback was invoked */\r
+ PaTime outputBufferDacTime; /**< The time when the first sample of the output buffer will output the DAC */\r
+} PaStreamCallbackTimeInfo;\r
+\r
+\r
+/**\r
+ Flag bit constants for the statusFlags to PaStreamCallback.\r
+\r
+ @see paInputUnderflow, paInputOverflow, paOutputUnderflow, paOutputOverflow,\r
+ paPrimingOutput\r
+*/\r
+typedef unsigned long PaStreamCallbackFlags;\r
+\r
+/** In a stream opened with paFramesPerBufferUnspecified, indicates that\r
+ input data is all silence (zeros) because no real data is available. In a\r
+ stream opened without paFramesPerBufferUnspecified, it indicates that one or\r
+ more zero samples have been inserted into the input buffer to compensate\r
+ for an input underflow.\r
+ @see PaStreamCallbackFlags\r
+*/\r
+#define paInputUnderflow ((PaStreamCallbackFlags) 0x00000001)\r
+\r
+/** In a stream opened with paFramesPerBufferUnspecified, indicates that data\r
+ prior to the first sample of the input buffer was discarded due to an\r
+ overflow, possibly because the stream callback is using too much CPU time.\r
+ Otherwise indicates that data prior to one or more samples in the\r
+ input buffer was discarded.\r
+ @see PaStreamCallbackFlags\r
+*/\r
+#define paInputOverflow ((PaStreamCallbackFlags) 0x00000002)\r
+\r
+/** Indicates that output data (or a gap) was inserted, possibly because the\r
+ stream callback is using too much CPU time.\r
+ @see PaStreamCallbackFlags\r
+*/\r
+#define paOutputUnderflow ((PaStreamCallbackFlags) 0x00000004)\r
+\r
+/** Indicates that output data will be discarded because no room is available.\r
+ @see PaStreamCallbackFlags\r
+*/\r
+#define paOutputOverflow ((PaStreamCallbackFlags) 0x00000008)\r
+\r
+/** Some of all of the output data will be used to prime the stream, input\r
+ data may be zero.\r
+ @see PaStreamCallbackFlags\r
+*/\r
+#define paPrimingOutput ((PaStreamCallbackFlags) 0x00000010)\r
+\r
+/**\r
+ Allowable return values for the PaStreamCallback.\r
+ @see PaStreamCallback\r
+*/\r
+typedef enum PaStreamCallbackResult\r
+{\r
+ paContinue=0, /**< Signal that the stream should continue invoking the callback and processing audio. */\r
+ paComplete=1, /**< Signal that the stream should stop invoking the callback and finish once all output samples have played. */\r
+ paAbort=2 /**< Signal that the stream should stop invoking the callback and finish as soon as possible. */\r
+} PaStreamCallbackResult;\r
+\r
+\r
+/**\r
+ Functions of type PaStreamCallback are implemented by PortAudio clients.\r
+ They consume, process or generate audio in response to requests from an\r
+ active PortAudio stream.\r
+\r
+ When a stream is running, PortAudio calls the stream callback periodically.\r
+ The callback function is responsible for processing buffers of audio samples \r
+ passed via the input and output parameters.\r
+\r
+ The PortAudio stream callback runs at very high or real-time priority.\r
+ It is required to consistently meet its time deadlines. Do not allocate \r
+ memory, access the file system, call library functions or call other functions \r
+ from the stream callback that may block or take an unpredictable amount of\r
+ time to complete.\r
+\r
+ In order for a stream to maintain glitch-free operation the callback\r
+ must consume and return audio data faster than it is recorded and/or\r
+ played. PortAudio anticipates that each callback invocation may execute for \r
+ a duration approaching the duration of frameCount audio frames at the stream \r
+ sample rate. It is reasonable to expect to be able to utilise 70% or more of\r
+ the available CPU time in the PortAudio callback. However, due to buffer size \r
+ adaption and other factors, not all host APIs are able to guarantee audio \r
+ stability under heavy CPU load with arbitrary fixed callback buffer sizes. \r
+ When high callback CPU utilisation is required the most robust behavior \r
+ can be achieved by using paFramesPerBufferUnspecified as the \r
+ Pa_OpenStream() framesPerBuffer parameter.\r
+ \r
+ @param input and @param output are either arrays of interleaved samples or;\r
+ if non-interleaved samples were requested using the paNonInterleaved sample \r
+ format flag, an array of buffer pointers, one non-interleaved buffer for \r
+ each channel.\r
+\r
+ The format, packing and number of channels used by the buffers are\r
+ determined by parameters to Pa_OpenStream().\r
+ \r
+ @param frameCount The number of sample frames to be processed by\r
+ the stream callback.\r
+\r
+ @param timeInfo Timestamps indicating the ADC capture time of the first sample\r
+ in the input buffer, the DAC output time of the first sample in the output buffer\r
+ and the time the callback was invoked. \r
+ See PaStreamCallbackTimeInfo and Pa_GetStreamTime()\r
+\r
+ @param statusFlags Flags indicating whether input and/or output buffers\r
+ have been inserted or will be dropped to overcome underflow or overflow\r
+ conditions.\r
+\r
+ @param userData The value of a user supplied pointer passed to\r
+ Pa_OpenStream() intended for storing synthesis data etc.\r
+\r
+ @return\r
+ The stream callback should return one of the values in the\r
+ ::PaStreamCallbackResult enumeration. To ensure that the callback continues\r
+ to be called, it should return paContinue (0). Either paComplete or paAbort\r
+ can be returned to finish stream processing, after either of these values is\r
+ returned the callback will not be called again. If paAbort is returned the\r
+ stream will finish as soon as possible. If paComplete is returned, the stream\r
+ will continue until all buffers generated by the callback have been played.\r
+ This may be useful in applications such as soundfile players where a specific\r
+ duration of output is required. However, it is not necessary to utilize this\r
+ mechanism as Pa_StopStream(), Pa_AbortStream() or Pa_CloseStream() can also\r
+ be used to stop the stream. The callback must always fill the entire output\r
+ buffer irrespective of its return value.\r
+\r
+ @see Pa_OpenStream, Pa_OpenDefaultStream\r
+\r
+ @note With the exception of Pa_GetStreamCpuLoad() it is not permissible to call\r
+ PortAudio API functions from within the stream callback.\r
+*/\r
+typedef int PaStreamCallback(\r
+ const void *input, void *output,\r
+ unsigned long frameCount,\r
+ const PaStreamCallbackTimeInfo* timeInfo,\r
+ PaStreamCallbackFlags statusFlags,\r
+ void *userData );\r
+\r
+\r
+/** Opens a stream for either input, output or both.\r
+ \r
+ @param stream The address of a PaStream pointer which will receive\r
+ a pointer to the newly opened stream.\r
+ \r
+ @param inputParameters A structure that describes the input parameters used by\r
+ the opened stream. See PaStreamParameters for a description of these parameters.\r
+ inputParameters must be NULL for output-only streams.\r
+\r
+ @param outputParameters A structure that describes the output parameters used by\r
+ the opened stream. See PaStreamParameters for a description of these parameters.\r
+ outputParameters must be NULL for input-only streams.\r
+ \r
+ @param sampleRate The desired sampleRate. For full-duplex streams it is the\r
+ sample rate for both input and output\r
+ \r
+ @param framesPerBuffer The number of frames passed to the stream callback\r
+ function, or the preferred block granularity for a blocking read/write stream.\r
+ The special value paFramesPerBufferUnspecified (0) may be used to request that\r
+ the stream callback will receive an optimal (and possibly varying) number of\r
+ frames based on host requirements and the requested latency settings.\r
+ Note: With some host APIs, the use of non-zero framesPerBuffer for a callback\r
+ stream may introduce an additional layer of buffering which could introduce\r
+ additional latency. PortAudio guarantees that the additional latency\r
+ will be kept to the theoretical minimum however, it is strongly recommended\r
+ that a non-zero framesPerBuffer value only be used when your algorithm\r
+ requires a fixed number of frames per stream callback.\r
+ \r
+ @param streamFlags Flags which modify the behavior of the streaming process.\r
+ This parameter may contain a combination of flags ORed together. Some flags may\r
+ only be relevant to certain buffer formats.\r
+ \r
+ @param streamCallback A pointer to a client supplied function that is responsible\r
+ for processing and filling input and output buffers. If this parameter is NULL\r
+ the stream will be opened in 'blocking read/write' mode. In blocking mode,\r
+ the client can receive sample data using Pa_ReadStream and write sample data\r
+ using Pa_WriteStream, the number of samples that may be read or written\r
+ without blocking is returned by Pa_GetStreamReadAvailable and\r
+ Pa_GetStreamWriteAvailable respectively.\r
+\r
+ @param userData A client supplied pointer which is passed to the stream callback\r
+ function. It could for example, contain a pointer to instance data necessary\r
+ for processing the audio buffers. This parameter is ignored if streamCallback\r
+ is NULL.\r
+ \r
+ @return\r
+ Upon success Pa_OpenStream() returns paNoError and places a pointer to a\r
+ valid PaStream in the stream argument. The stream is inactive (stopped).\r
+ If a call to Pa_OpenStream() fails, a non-zero error code is returned (see\r
+ PaError for possible error codes) and the value of stream is invalid.\r
+\r
+ @see PaStreamParameters, PaStreamCallback, Pa_ReadStream, Pa_WriteStream,\r
+ Pa_GetStreamReadAvailable, Pa_GetStreamWriteAvailable\r
+*/\r
+PaError Pa_OpenStream( PaStream** stream,\r
+ const PaStreamParameters *inputParameters,\r
+ const PaStreamParameters *outputParameters,\r
+ double sampleRate,\r
+ unsigned long framesPerBuffer,\r
+ PaStreamFlags streamFlags,\r
+ PaStreamCallback *streamCallback,\r
+ void *userData );\r
+\r
+\r
+/** A simplified version of Pa_OpenStream() that opens the default input\r
+ and/or output devices.\r
+\r
+ @param stream The address of a PaStream pointer which will receive\r
+ a pointer to the newly opened stream.\r
+ \r
+ @param numInputChannels The number of channels of sound that will be supplied\r
+ to the stream callback or returned by Pa_ReadStream. It can range from 1 to\r
+ the value of maxInputChannels in the PaDeviceInfo record for the default input\r
+ device. If 0 the stream is opened as an output-only stream.\r
+\r
+ @param numOutputChannels The number of channels of sound to be delivered to the\r
+ stream callback or passed to Pa_WriteStream. It can range from 1 to the value\r
+ of maxOutputChannels in the PaDeviceInfo record for the default output device.\r
+ If 0 the stream is opened as an output-only stream.\r
+\r
+ @param sampleFormat The sample format of both the input and output buffers\r
+ provided to the callback or passed to and from Pa_ReadStream and Pa_WriteStream.\r
+ sampleFormat may be any of the formats described by the PaSampleFormat\r
+ enumeration.\r
+ \r
+ @param sampleRate Same as Pa_OpenStream parameter of the same name.\r
+ @param framesPerBuffer Same as Pa_OpenStream parameter of the same name.\r
+ @param streamCallback Same as Pa_OpenStream parameter of the same name.\r
+ @param userData Same as Pa_OpenStream parameter of the same name.\r
+\r
+ @return As for Pa_OpenStream\r
+\r
+ @see Pa_OpenStream, PaStreamCallback\r
+*/\r
+PaError Pa_OpenDefaultStream( PaStream** stream,\r
+ int numInputChannels,\r
+ int numOutputChannels,\r
+ PaSampleFormat sampleFormat,\r
+ double sampleRate,\r
+ unsigned long framesPerBuffer,\r
+ PaStreamCallback *streamCallback,\r
+ void *userData );\r
+\r
+\r
+/** Closes an audio stream. If the audio stream is active it\r
+ discards any pending buffers as if Pa_AbortStream() had been called.\r
+*/\r
+PaError Pa_CloseStream( PaStream *stream );\r
+\r
+\r
+/** Functions of type PaStreamFinishedCallback are implemented by PortAudio \r
+ clients. They can be registered with a stream using the Pa_SetStreamFinishedCallback\r
+ function. Once registered they are called when the stream becomes inactive\r
+ (ie once a call to Pa_StopStream() will not block).\r
+ A stream will become inactive after the stream callback returns non-zero,\r
+ or when Pa_StopStream or Pa_AbortStream is called. For a stream providing audio\r
+ output, if the stream callback returns paComplete, or Pa_StopStream is called,\r
+ the stream finished callback will not be called until all generated sample data\r
+ has been played.\r
+ \r
+ @param userData The userData parameter supplied to Pa_OpenStream()\r
+\r
+ @see Pa_SetStreamFinishedCallback\r
+*/\r
+typedef void PaStreamFinishedCallback( void *userData );\r
+\r
+\r
+/** Register a stream finished callback function which will be called when the \r
+ stream becomes inactive. See the description of PaStreamFinishedCallback for \r
+ further details about when the callback will be called.\r
+\r
+ @param stream a pointer to a PaStream that is in the stopped state - if the\r
+ stream is not stopped, the stream's finished callback will remain unchanged \r
+ and an error code will be returned.\r
+\r
+ @param streamFinishedCallback a pointer to a function with the same signature\r
+ as PaStreamFinishedCallback, that will be called when the stream becomes\r
+ inactive. Passing NULL for this parameter will un-register a previously\r
+ registered stream finished callback function.\r
+\r
+ @return on success returns paNoError, otherwise an error code indicating the cause\r
+ of the error.\r
+\r
+ @see PaStreamFinishedCallback\r
+*/\r
+PaError Pa_SetStreamFinishedCallback( PaStream *stream, PaStreamFinishedCallback* streamFinishedCallback ); \r
+\r
+\r
+/** Commences audio processing.\r
+*/\r
+PaError Pa_StartStream( PaStream *stream );\r
+\r
+\r
+/** Terminates audio processing. It waits until all pending\r
+ audio buffers have been played before it returns.\r
+*/\r
+PaError Pa_StopStream( PaStream *stream );\r
+\r
+\r
+/** Terminates audio processing immediately without waiting for pending\r
+ buffers to complete.\r
+*/\r
+PaError Pa_AbortStream( PaStream *stream );\r
+\r
+\r
+/** Determine whether the stream is stopped.\r
+ A stream is considered to be stopped prior to a successful call to\r
+ Pa_StartStream and after a successful call to Pa_StopStream or Pa_AbortStream.\r
+ If a stream callback returns a value other than paContinue the stream is NOT\r
+ considered to be stopped.\r
+\r
+ @return Returns one (1) when the stream is stopped, zero (0) when\r
+ the stream is running or, a PaErrorCode (which are always negative) if\r
+ PortAudio is not initialized or an error is encountered.\r
+\r
+ @see Pa_StopStream, Pa_AbortStream, Pa_IsStreamActive\r
+*/\r
+PaError Pa_IsStreamStopped( PaStream *stream );\r
+\r
+\r
+/** Determine whether the stream is active.\r
+ A stream is active after a successful call to Pa_StartStream(), until it\r
+ becomes inactive either as a result of a call to Pa_StopStream() or\r
+ Pa_AbortStream(), or as a result of a return value other than paContinue from\r
+ the stream callback. In the latter case, the stream is considered inactive\r
+ after the last buffer has finished playing.\r
+\r
+ @return Returns one (1) when the stream is active (ie playing or recording\r
+ audio), zero (0) when not playing or, a PaErrorCode (which are always negative)\r
+ if PortAudio is not initialized or an error is encountered.\r
+\r
+ @see Pa_StopStream, Pa_AbortStream, Pa_IsStreamStopped\r
+*/\r
+PaError Pa_IsStreamActive( PaStream *stream );\r
+\r
+\r
+\r
+/** A structure containing unchanging information about an open stream.\r
+ @see Pa_GetStreamInfo\r
+*/\r
+\r
+typedef struct PaStreamInfo\r
+{\r
+ /** this is struct version 1 */\r
+ int structVersion;\r
+\r
+ /** The input latency of the stream in seconds. This value provides the most\r
+ accurate estimate of input latency available to the implementation. It may\r
+ differ significantly from the suggestedLatency value passed to Pa_OpenStream().\r
+ The value of this field will be zero (0.) for output-only streams.\r
+ @see PaTime\r
+ */\r
+ PaTime inputLatency;\r
+\r
+ /** The output latency of the stream in seconds. This value provides the most\r
+ accurate estimate of output latency available to the implementation. It may\r
+ differ significantly from the suggestedLatency value passed to Pa_OpenStream().\r
+ The value of this field will be zero (0.) for input-only streams.\r
+ @see PaTime\r
+ */\r
+ PaTime outputLatency;\r
+\r
+ /** The sample rate of the stream in Hertz (samples per second). In cases\r
+ where the hardware sample rate is inaccurate and PortAudio is aware of it,\r
+ the value of this field may be different from the sampleRate parameter\r
+ passed to Pa_OpenStream(). If information about the actual hardware sample\r
+ rate is not available, this field will have the same value as the sampleRate\r
+ parameter passed to Pa_OpenStream().\r
+ */\r
+ double sampleRate;\r
+ \r
+} PaStreamInfo;\r
+\r
+\r
+/** Retrieve a pointer to a PaStreamInfo structure containing information\r
+ about the specified stream.\r
+ @return A pointer to an immutable PaStreamInfo structure. If the stream\r
+ parameter invalid, or an error is encountered, the function returns NULL.\r
+\r
+ @param stream A pointer to an open stream previously created with Pa_OpenStream.\r
+\r
+ @note PortAudio manages the memory referenced by the returned pointer,\r
+ the client must not manipulate or free the memory. The pointer is only\r
+ guaranteed to be valid until the specified stream is closed.\r
+\r
+ @see PaStreamInfo\r
+*/\r
+const PaStreamInfo* Pa_GetStreamInfo( PaStream *stream );\r
+\r
+\r
+/** Returns the current time in seconds for a stream according to the same clock used\r
+ to generate callback PaStreamCallbackTimeInfo timestamps. The time values are\r
+ monotonically increasing and have unspecified origin. \r
+ \r
+ Pa_GetStreamTime returns valid time values for the entire life of the stream,\r
+ from when the stream is opened until it is closed. Starting and stopping the stream\r
+ does not affect the passage of time returned by Pa_GetStreamTime.\r
+\r
+ This time may be used for synchronizing other events to the audio stream, for \r
+ example synchronizing audio to MIDI.\r
+ \r
+ @return The stream's current time in seconds, or 0 if an error occurred.\r
+\r
+ @see PaTime, PaStreamCallback, PaStreamCallbackTimeInfo\r
+*/\r
+PaTime Pa_GetStreamTime( PaStream *stream );\r
+\r
+\r
+/** Retrieve CPU usage information for the specified stream.\r
+ The "CPU Load" is a fraction of total CPU time consumed by a callback stream's\r
+ audio processing routines including, but not limited to the client supplied\r
+ stream callback. This function does not work with blocking read/write streams.\r
+\r
+ This function may be called from the stream callback function or the\r
+ application.\r
+ \r
+ @return\r
+ A floating point value, typically between 0.0 and 1.0, where 1.0 indicates\r
+ that the stream callback is consuming the maximum number of CPU cycles possible\r
+ to maintain real-time operation. A value of 0.5 would imply that PortAudio and\r
+ the stream callback was consuming roughly 50% of the available CPU time. The\r
+ return value may exceed 1.0. A value of 0.0 will always be returned for a\r
+ blocking read/write stream, or if an error occurs.\r
+*/\r
+double Pa_GetStreamCpuLoad( PaStream* stream );\r
+\r
+\r
+/** Read samples from an input stream. The function doesn't return until\r
+ the entire buffer has been filled - this may involve waiting for the operating\r
+ system to supply the data.\r
+\r
+ @param stream A pointer to an open stream previously created with Pa_OpenStream.\r
+ \r
+ @param buffer A pointer to a buffer of sample frames. The buffer contains\r
+ samples in the format specified by the inputParameters->sampleFormat field\r
+ used to open the stream, and the number of channels specified by\r
+ inputParameters->numChannels. If non-interleaved samples were requested using\r
+ the paNonInterleaved sample format flag, buffer is a pointer to the first element \r
+ of an array of buffer pointers, one non-interleaved buffer for each channel.\r
+\r
+ @param frames The number of frames to be read into buffer. This parameter\r
+ is not constrained to a specific range, however high performance applications\r
+ will want to match this parameter to the framesPerBuffer parameter used\r
+ when opening the stream.\r
+\r
+ @return On success PaNoError will be returned, or PaInputOverflowed if input\r
+ data was discarded by PortAudio after the previous call and before this call.\r
+*/\r
+PaError Pa_ReadStream( PaStream* stream,\r
+ void *buffer,\r
+ unsigned long frames );\r
+\r
+\r
+/** Write samples to an output stream. This function doesn't return until the\r
+ entire buffer has been consumed - this may involve waiting for the operating\r
+ system to consume the data.\r
+\r
+ @param stream A pointer to an open stream previously created with Pa_OpenStream.\r
+\r
+ @param buffer A pointer to a buffer of sample frames. The buffer contains\r
+ samples in the format specified by the outputParameters->sampleFormat field\r
+ used to open the stream, and the number of channels specified by\r
+ outputParameters->numChannels. If non-interleaved samples were requested using\r
+ the paNonInterleaved sample format flag, buffer is a pointer to the first element \r
+ of an array of buffer pointers, one non-interleaved buffer for each channel.\r
+\r
+ @param frames The number of frames to be written from buffer. This parameter\r
+ is not constrained to a specific range, however high performance applications\r
+ will want to match this parameter to the framesPerBuffer parameter used\r
+ when opening the stream.\r
+\r
+ @return On success PaNoError will be returned, or paOutputUnderflowed if\r
+ additional output data was inserted after the previous call and before this\r
+ call.\r
+*/\r
+PaError Pa_WriteStream( PaStream* stream,\r
+ const void *buffer,\r
+ unsigned long frames );\r
+\r
+\r
+/** Retrieve the number of frames that can be read from the stream without\r
+ waiting.\r
+\r
+ @return Returns a non-negative value representing the maximum number of frames\r
+ that can be read from the stream without blocking or busy waiting or, a\r
+ PaErrorCode (which are always negative) if PortAudio is not initialized or an\r
+ error is encountered.\r
+*/\r
+signed long Pa_GetStreamReadAvailable( PaStream* stream );\r
+\r
+\r
+/** Retrieve the number of frames that can be written to the stream without\r
+ waiting.\r
+\r
+ @return Returns a non-negative value representing the maximum number of frames\r
+ that can be written to the stream without blocking or busy waiting or, a\r
+ PaErrorCode (which are always negative) if PortAudio is not initialized or an\r
+ error is encountered.\r
+*/\r
+signed long Pa_GetStreamWriteAvailable( PaStream* stream );\r
+\r
+\r
+/* Miscellaneous utilities */\r
+\r
+\r
+/** Retrieve the size of a given sample format in bytes.\r
+\r
+ @return The size in bytes of a single sample in the specified format,\r
+ or paSampleFormatNotSupported if the format is not supported.\r
+*/\r
+PaError Pa_GetSampleSize( PaSampleFormat format );\r
+\r
+\r
+/** Put the caller to sleep for at least 'msec' milliseconds. This function is\r
+ provided only as a convenience for authors of portable code (such as the tests\r
+ and examples in the PortAudio distribution.)\r
+\r
+ The function may sleep longer than requested so don't rely on this for accurate\r
+ musical timing.\r
+*/\r
+void Pa_Sleep( long msec );\r
+\r
+\r
+\r
+#ifdef __cplusplus\r
+}\r
+#endif /* __cplusplus */\r
+#endif /* PORTAUDIO_H */\r
projects / freetel-svn-tracking.git / commitdiff