IVMRSurfaceAllocatorEx9 Interface

Microsoft DirectShow 9.0

IVMRSurfaceAllocatorEx9 Interface

This topic applies to Windows XP Service Pack 2 and later.

The IVMRSurfaceAllocatorEx9 interface provides a way for custom allocator-presenters to control where the Video Mixing Renderer Filter 9 (VMR-9) draws the composited image.

To use this interface, implement it on your allocator-presenter. At the start of each frame, the VMR-9 calls QueryInterface on the allocator-presenter for the IVMRSurfaceAllocatorEx9 interface. If the allocator-presenter returns the interface, the VMR-9 calls the GetSurfaceEx method instead of the usual IVMRSurfaceAllocator9::GetSurface method. This enables your allocator-presenter to specify the rectangle within the returned IDirect3DSurface9 where the composed video image will be written. This feature enables all of the video image scaling operations to be performed in a single stage, and is available in both RGB and YUV mixing modes.

In addition to the methods inherited from IUnknown, the IVMRSurfaceAllocatorEx9 interface exposes the following method.

Method	Description
GetSurfaceEx	Retrieves a Direct3D surface and a destination rectangle.

Requirements

Header: Include D3d9.h, Vmr9.h.

Library: Use Strmiids.lib.