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4/8/2010

This class provides support for IMemAllocatorby using the newoperator to allocate memory.

Derived from CBaseAllocator, it overrides the CBaseAllocator::Allocmember function to allocate a single block of memory large enough to hold all requested data areas, and then allocates (using the newoperator) a CMediaSampleobject for each requested buffer pointing into the data area.

The CBaseInputPinand CBaseOutputPinclasses instantiate CMemAllocatorobjects as the default allocator if no other suitable allocator is provided.

All member functions in this class that return HRESULTand accept a pointer as a parameter return E_POINTER when passed a null pointer.

Member Functions

Member function Description

Alloc

Allocates memory for a media sample (overrides CBaseAllocator::Alloc).

CMemAllocator

Constructs a CMemAllocatorobject.

ReallyFree

Frees memory when called from the destructor (or from Allocwhen reallocating for new size or count).

Overrideable Member Functions

Member function Description

Free

Indicates an overridden CBaseAllocator::Freemember function, called when a decommit operation is complete to free memory.

Implemented IMemAllocator Methods

Method Description

CreateInstance

Creates new instances of CMemAllocator in the factory template.

SetProperties

Sets the number of media samples and the size of each.

Requirements

Windows Embedded CE Windows CE 2.12 and later
Windows Mobile Windows Mobile Version 5.0 and later
Note Microsoft DirectShow applications and DirectShow filters have different include file and Library requirements
For more information, see Setting Up the Build Environment