IXAPO::LockForProcess method (xapo.h)

Article
10/05/2021

Called by XAudio2 to lock the input and output configurations of an XAPO allowing it to do any final initialization before Process is called on the realtime thread.

Syntax

HRESULT LockForProcess(
  UINT32                               InputLockedParameterCount,
  const XAPO_LOCKFORPROCESS_PARAMETERS *pInputLockedParameters,
  UINT32                               OutputLockedParameterCount,
  const XAPO_LOCKFORPROCESS_PARAMETERS *pOutputLockedParameters
);

Parameters

InputLockedParameterCount

Number of elements in ppInputLockedParameters. Must be within the XAPO_REGISTRATION_PROPERTIES.MinInputBufferCount and XAPO_REGISTRATION_PROPERTIES.MaxInputBufferCount values passed to CXAPOBase::CXAPOBase.

pInputLockedParameters

Array of input XAPO_LOCKFORPROCESS_BUFFER_PARAMETERS structures. pInputLockedParameters may be NULL if InputLockedParameterCount is 0, otherwise it must have InputLockedParameterCount elements.

OutputLockedParameterCount

Number of elements in ppOutputLockedParameters. Must be within the XAPO_REGISTRATION_PROPERTIES.MinOutputBufferCount and XAPO_REGISTRATION_PROPERTIES.MaxOutputBufferCount values passed to CXAPOBase::CXAPOBase. If the XAPO_FLAG_BUFFERCOUNT_MUST_MATCH flag was specified in XAPO_REGISTRATION_PROPERTIES.Flags then OutputLockedParameterCount must equal InputLockedParameterCount.

pOutputLockedParameters

Array of output XAPO_LOCKFORPROCESS_BUFFER_PARAMETERS structures. pOutputLockedParameters may be NULL if OutputLockedParameterCount is 0, otherwise it must have OutputLockedParameterCount elements.

Return value

Returns S_OK if successful, an error code otherwise.

Remarks

Once locked, the input and output configuration and any other locked parameters remain constant until UnLockForProcess is called. After an XAPO is locked, further calls to LockForProcess have no effect until the UnLockForProcess function is called.

An XAPO indicates what specific formats it supports through its implementation of the IsInputFormatSupported and IsOutputFormatSupported methods. An XAPO should assert the input and output configurations are supported and that any required effect-specific initialization is complete. The IsInputFormatSupported, IsOutputFormatSupported, and Initialize methods should be used as necessary before calling this method.

Because Process is a nonblocking method, all internal memory buffers required for Process should be allocated in LockForProcess.

Process is never called before LockForProcess returns successfully.

LockForProcess is called directly by XAudio2 and should not be called by the client code.

Platform Requirements

Windows 10 (XAudio2.9); Windows 8, Windows Phone 8 (XAudio 2.8); DirectX SDK (XAudio 2.7)

Requirements

Requirement	Value
Target Platform	Windows
Header	xapo.h