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IltmmMemory::CopyData

Summary

Copies a block of data to a user-defined buffer.

Syntax

#include "ltmm.h"

Language	Syntax
C	HRESULT IltmmMemory_CopyData(pMem, Index, Count, Data)
C++	HRESULT CopyData(Index, Count, Data)

Parameters

IltmmMemory *pMem

Pointer to an IltmmMemory interface.

long Index

Index, or offset, in the objects buffer, from which to retrieve the data.

long Count

Size of the data to retrieve (number of elements in bytes).

VARIANT *Data

Pointer to a variable to be updated with a VARIANT containing a SAFEARRAY reference to the block of data.

Returns

Value	Meaning
S_OK	The function was successful.
<> S_OK	An error occurred. Refer to the Error Codes or the HRESULT error codes in the DirectShow documentation.

Comments

If the size of the data to retrieve is larger than the size available after the offset, the function will retrieve only the available data between the offset and the end of the buffer.

In the IltmmMemory::GetData function the function itself allocates the memory for the SAFEARRAY. In this function the caller is responsible for allocating the required memory for the SAFEARRAY.

The area of the object's buffer from which the data is copied will be locked for the duration of the call.