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diff --git a/portaudio/include/portaudio.h b/portaudio/include/portaudio.h new file mode 100644 index 0000000..5d84731 --- /dev/null +++ b/portaudio/include/portaudio.h @@ -0,0 +1,1228 @@ +#ifndef PORTAUDIO_H +#define PORTAUDIO_H +/* + * $Id$ + * 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. + For example, for version "19.5.1" this will return 0x00130501. + + @see paMakeVersionNumber +*/ +int Pa_GetVersion( void ); + +/** Retrieve a textual description of the current PortAudio build, + e.g. "PortAudio V19.5.0-devel, revision 1952M". + The format of the text may change in the future. Do not try to parse the + returned string. + + @deprecated As of 19.5.0, use Pa_GetVersionInfo()->versionText instead. +*/ +const char* Pa_GetVersionText( void ); + +/** + Generate a packed integer version number in the same format used + by Pa_GetVersion(). Use this to compare a specified version number with + the currently running version. For example: + + @code + if( Pa_GetVersion() < paMakeVersionNumber(19,5,1) ) {} + @endcode + + @see Pa_GetVersion, Pa_GetVersionInfo + @version Available as of 19.5.0. +*/ +#define paMakeVersionNumber(major, minor, subminor) \ + (((major)&0xFF)<<16 | ((minor)&0xFF)<<8 | ((subminor)&0xFF)) + + +/** + A structure containing PortAudio API version information. + @see Pa_GetVersionInfo, paMakeVersionNumber + @version Available as of 19.5.0. +*/ +typedef struct PaVersionInfo { + int versionMajor; + int versionMinor; + int versionSubMinor; + /** + This is currently the Git revision hash but may change in the future. + The versionControlRevision is updated by running a script before compiling the library. + If the update does not occur, this value may refer to an earlier revision. + */ + const char *versionControlRevision; + /** Version as a string, for example "PortAudio V19.5.0-devel, revision 1952M" */ + const char *versionText; +} PaVersionInfo; + +/** Retrieve version information for the currently running PortAudio build. + @return A pointer to an immutable PaVersionInfo structure. + + @note This function can be called at any time. It does not require PortAudio + to be initialized. The structure pointed to is statically allocated. Do not + attempt to free it or modify it. + + @see PaVersionInfo, paMakeVersionNumber + @version Available as of 19.5.0. +*/ +const PaVersionInfo* Pa_GetVersionInfo( 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. Note that the actual sampleRate + may differ very slightly from the desired rate because of hardware limitations. + The exact rate can be queried using Pa_GetStreamInfo(). If nothing close + to the desired sampleRate is available then the open will fail and return an error. + + @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 is 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 written - 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 */ |