Class: AudiobufferPool

Overview

Memory allocation is a blocking operation, therefore should be avoided in a real-time audio context. AudiobufferPool can allocate audio buffers from pre-allocated memory without any blocking. Every buffer has a retain count which can be incremented by calling retain and decremented by calling release. Whenever the retain count value reaches zero, the buffer is destroyed and its memory will be automatically reused for another buffer.

How to implement

AudiobufferPool::initialize();
...
void *buffer = AudiobufferPool::getBuffer(128); // Returns a 128 byte buffer with retain count set to 1
AudiobufferPool::retainBuffer(buffer); // Retains buffer (retain count = 2)
AudiobufferPool::releaseBuffer(buffer); // Releases buffer (retain count = 1)
AudiobufferPool::releaseBuffer(buffer); // Releases buffer

Methods

• getBuffer

  METHOD

  Creates a buffer with retain count set to 1, similar to an NSObject in Objective-C. Use releaseBuffer() to release. This method never blocks, never locks, is very fast and safe to use in a realtime thread. Can be called concurrently on any thread.

  Parameters

  Name	Type	Default	Description
  sizeBytes	unsigned int		The requested buffer's size in bytes. Maximum: 8388608 (8 MB).

  Returns

  Type	Description
  void *	The buffer.

• initialize

  METHOD

  Initializes the buffer pool.

  Parameters

  None

  Returns

  None

• releaseBuffer

  METHOD

  Release a buffer, similar to an NSObject in Objective-C (decreases the retain count by 1, the memory will be freed after retain count reaches 0). This method never blocks, never locks, is very fast and safe to use in a realtime thread. Can be called concurrently on any thread.

  Parameters

  Name	Type	Default	Description
  buffer	void *		The buffer.

  Returns

  None

• retainBuffer

  METHOD

  Retains a buffer, similar to Objective-C (increases the retain count by 1, similar to an NSObject in Objective-C). This method never blocks, never locks, is very fast and safe to use in a realtime thread. Can be called concurrently on any thread.

  Parameters

  Name	Type	Default	Description
  buffer	void *		The buffer.

  Returns

  None