#include "TPCircularBuffer.h"
#include <AudioToolbox/AudioToolbox.h>

Classes
struct	TPCircularBufferABLBlockHeader

Macros
#define	kTPCircularBufferCopyAll UINT32_MAX

Functions
AudioBufferList *	TPCircularBufferPrepareEmptyAudioBufferList (TPCircularBuffer buffer, int numberOfBuffers, int bytesPerBuffer, const AudioTimeStamp timestamp)
	Prepare an empty buffer list, stored on the circular buffer.

AudioBufferList *	TPCircularBufferPrepareEmptyAudioBufferListWithAudioFormat (TPCircularBuffer buffer, const AudioStreamBasicDescription audioFormat, UInt32 frameCount, const AudioTimeStamp *timestamp)
	Prepare an empty buffer list, stored on the circular buffer, using an audio description to automatically configure buffer.

void	TPCircularBufferProduceAudioBufferList (TPCircularBuffer buffer, const AudioTimeStamp inTimestamp)
	Mark next audio buffer list as ready for reading.

bool	TPCircularBufferCopyAudioBufferList (TPCircularBuffer buffer, const AudioBufferList bufferList, const AudioTimeStamp timestamp, UInt32 frames, const AudioStreamBasicDescription audioFormat)
	Copy the audio buffer list onto the buffer.

	if (!block)

	if (outTimestamp)

AudioBufferList *	TPCircularBufferNextBufferListAfter (TPCircularBuffer buffer, const AudioBufferList bufferList, AudioTimeStamp *outTimestamp)
	Get a pointer to the next stored buffer list after the given one.

void	TPCircularBufferConsumeNextBufferListPartial (TPCircularBuffer buffer, int framesToConsume, const AudioStreamBasicDescription audioFormat)
	Consume a portion of the next buffer list.

void	TPCircularBufferDequeueBufferListFrames (TPCircularBuffer buffer, UInt32 ioLengthInFrames, const AudioBufferList outputBufferList, AudioTimeStamp outTimestamp, const AudioStreamBasicDescription *audioFormat)
	Consume a certain number of frames from the buffer, possibly from multiple queued buffer lists.

UInt32	TPCircularBufferPeek (TPCircularBuffer buffer, AudioTimeStamp outTimestamp, const AudioStreamBasicDescription *audioFormat)
	Determine how many frames of audio are buffered.

UInt32	TPCircularBufferPeekContiguous (TPCircularBuffer buffer, AudioTimeStamp outTimestamp, const AudioStreamBasicDescription *audioFormat, UInt32 contiguousToleranceSampleTime)
	Determine how many contiguous frames of audio are buffered.

UInt32	TPCircularBufferPeekContiguousWrapped (TPCircularBuffer buffer, AudioTimeStamp outTimestamp, const AudioStreamBasicDescription *audioFormat, UInt32 contiguousToleranceSampleTime, UInt32 wrapPoint)
	Determine how many contiguous frames of audio are buffered, with wrap around.

UInt32	TPCircularBufferGetAvailableSpace (TPCircularBuffer buffer, const AudioStreamBasicDescription audioFormat)
	Determine how many much space there is in the buffer.

Variables
static __inline__ AudioTimeStamp *	outTimestamp

TPCircularBufferABLBlockHeader *	block = (TPCircularBufferABLBlockHeader*)TPCircularBufferTail(buffer, &dontcare)

return &block	bufferList

Class Documentation

struct TPCircularBufferABLBlockHeader

Class Members
AudioTimeStamp	timestamp
UInt32	totalLength
AudioBufferList	bufferList

Macro Definition Documentation

#define kTPCircularBufferCopyAll UINT32_MAX

Function Documentation

AudioBufferList* TPCircularBufferPrepareEmptyAudioBufferList	(	TPCircularBuffer *	buffer,
		int	numberOfBuffers,
		int	bytesPerBuffer,
		const AudioTimeStamp *	timestamp
	)

Prepare an empty buffer list, stored on the circular buffer.

Parameters

buffer	Circular buffer
numberOfBuffers	The number of buffers to be contained within the buffer list
bytesPerBuffer	The number of bytes to store for each buffer
timestamp	The timestamp associated with the buffer, or NULL. Note that you can also pass a timestamp into TPCircularBufferProduceAudioBufferList, to set it there instead.

Returns: The empty buffer list, or NULL if circular buffer has insufficient space

AudioBufferList* TPCircularBufferPrepareEmptyAudioBufferListWithAudioFormat	(	TPCircularBuffer *	buffer,
		const AudioStreamBasicDescription *	audioFormat,
		UInt32	frameCount,
		const AudioTimeStamp *	timestamp
	)

Prepare an empty buffer list, stored on the circular buffer, using an audio description to automatically configure buffer.

Parameters

buffer	Circular buffer
audioFormat	The kind of audio that will be stored
frameCount	The number of frames that will be stored
timestamp	The timestamp associated with the buffer, or NULL. Note that you can also pass a timestamp into TPCircularBufferProduceAudioBufferList, to set it there instead.

Returns: The empty buffer list, or NULL if circular buffer has insufficient space

void TPCircularBufferProduceAudioBufferList	(	TPCircularBuffer *	buffer,
		const AudioTimeStamp *	inTimestamp
	)

Mark next audio buffer list as ready for reading.

This marks the audio buffer list prepared using TPCircularBufferPrepareEmptyAudioBufferList as ready for reading. You must not call this function without first calling TPCircularBufferPrepareEmptyAudioBufferList.

Parameters

buffer	Circular buffer
inTimestamp	The timestamp associated with the buffer, or NULL to leave as-is. Note that you can also pass a timestamp into TPCircularBufferPrepareEmptyAudioBufferList, to set it there instead.

bool TPCircularBufferCopyAudioBufferList	(	TPCircularBuffer *	buffer,
		const AudioBufferList *	bufferList,
		const AudioTimeStamp *	timestamp,
		UInt32	frames,
		const AudioStreamBasicDescription *	audioFormat
	)

Copy the audio buffer list onto the buffer.

Parameters

buffer	Circular buffer
bufferList	Buffer list containing audio to copy to buffer
timestamp	The timestamp associated with the buffer, or NULL
frames	Length of audio in frames. Specify kTPCircularBufferCopyAll to copy the whole buffer (audioFormat can be NULL, in this case)
audioFormat	The AudioStreamBasicDescription describing the audio, or NULL if you specify kTPCircularBufferCopyAll to the `frames` argument

Returns: YES if buffer list was successfully copied; NO if there was insufficient space

if ( ! block )

if ( outTimestamp )

AudioBufferList* TPCircularBufferNextBufferListAfter	(	TPCircularBuffer *	buffer,
		const AudioBufferList *	bufferList,
		AudioTimeStamp *	outTimestamp
	)

Get a pointer to the next stored buffer list after the given one.

Parameters

buffer	Circular buffer
bufferList	Preceding buffer list
outTimestamp	On output, if not NULL, the timestamp corresponding to the buffer

Returns: Pointer to the next buffer list in the buffer, or NULL

void TPCircularBufferConsumeNextBufferListPartial	(	TPCircularBuffer *	buffer,
		int	framesToConsume,
		const AudioStreamBasicDescription *	audioFormat
	)

Consume a portion of the next buffer list.

This will also increment the sample time and host time portions of the timestamp of the buffer list, if present.

Parameters

buffer	Circular buffer
framesToConsume	The number of frames to consume from the buffer list
audioFormat	The AudioStreamBasicDescription describing the audio

void TPCircularBufferDequeueBufferListFrames	(	TPCircularBuffer *	buffer,
		UInt32 *	ioLengthInFrames,
		const AudioBufferList *	outputBufferList,
		AudioTimeStamp *	outTimestamp,
		const AudioStreamBasicDescription *	audioFormat
	)

Consume a certain number of frames from the buffer, possibly from multiple queued buffer lists.

Copies the given number of frames from the buffer into outputBufferList, of the given audio description, then consumes the audio buffers. If an audio buffer has not been entirely consumed, then updates the queued buffer list structure to point to the unconsumed data only.

Parameters

buffer	Circular buffer
ioLengthInFrames	On input, the number of frames in the given audio format to consume; on output, the number of frames provided
outputBufferList	The buffer list to copy audio to, or NULL to discard audio. If not NULL, the structure must be initialised properly, and the mData pointers must not be NULL.
outTimestamp	On output, if not NULL, the timestamp corresponding to the first audio frame returned
audioFormat	The format of the audio stored in the buffer

UInt32 TPCircularBufferPeek	(	TPCircularBuffer *	buffer,
		AudioTimeStamp *	outTimestamp,
		const AudioStreamBasicDescription *	audioFormat
	)

Determine how many frames of audio are buffered.

Given the provided audio format, determines the frame count of all queued buffers

Note: This function should only be used on the consumer thread, not the producer thread.

Parameters

buffer	Circular buffer
outTimestamp	On output, if not NULL, the timestamp corresponding to the first audio frame
audioFormat	The format of the audio stored in the buffer

Returns: The number of frames in the given audio format that are in the buffer

UInt32 TPCircularBufferPeekContiguous	(	TPCircularBuffer *	buffer,
		AudioTimeStamp *	outTimestamp,
		const AudioStreamBasicDescription *	audioFormat,
		UInt32	contiguousToleranceSampleTime
	)

Determine how many contiguous frames of audio are buffered.

Given the provided audio format, determines the frame count of all queued buffers that are contiguous, given their corresponding timestamps (sample time).

Note: This function should only be used on the consumer thread, not the producer thread.

Parameters

buffer	Circular buffer
outTimestamp	On output, if not NULL, the timestamp corresponding to the first audio frame
audioFormat	The format of the audio stored in the buffer
contiguousToleranceSampleTime	The number of samples of discrepancy to tolerate

Returns: The number of frames in the given audio format that are in the buffer

UInt32 TPCircularBufferPeekContiguousWrapped	(	TPCircularBuffer *	buffer,
		AudioTimeStamp *	outTimestamp,
		const AudioStreamBasicDescription *	audioFormat,
		UInt32	contiguousToleranceSampleTime,
		UInt32	wrapPoint
	)

Determine how many contiguous frames of audio are buffered, with wrap around.

Like TPCircularBufferPeekContiguous, determines how many contiguous frames are buffered, but considers audio that wraps around a region of a given length as also contiguous. This is good for audio that loops.

Note: This function should only be used on the consumer thread, not the producer thread.

Parameters

buffer	Circular buffer
outTimestamp	On output, if not NULL, the timestamp corresponding to the first audio frame
audioFormat	The format of the audio stored in the buffer
contiguousToleranceSampleTime	The number of samples of discrepancy to tolerate
wrapPoint	The point around which the audio may wrap and still be considered contiguous, or 0 to disable

Returns: The number of frames in the given audio format that are in the buffer

UInt32 TPCircularBufferGetAvailableSpace	(	TPCircularBuffer *	buffer,
		const AudioStreamBasicDescription *	audioFormat
	)

Determine how many much space there is in the buffer.

Given the provided audio format, determines the number of frames of audio that can be buffered.

Note: This function should only be used on the producer thread, not the consumer thread.

Parameters

buffer	Circular buffer
audioFormat	The format of the audio stored in the buffer

Returns: The number of frames in the given audio format that can be stored in the buffer

Variable Documentation

__inline__ AudioTimeStamp* outTimestamp

Initial value:

{

int32_t dontcare

TPCircularBufferABLBlockHeader* block = (TPCircularBufferABLBlockHeader*)TPCircularBufferTail(buffer, &dontcare)

return& block bufferList

Classes

Macros

Functions

Variables

Class Documentation

Macro Definition Documentation

Function Documentation

Variable Documentation