Microsoft DirectX 8.0

IDVSplitter Interface

Downgrades the frame rate on a digital video (DV) stream. The DV Splitter filter exposes this interface.

Applications can use this interface to reduce the frame rate on a DV stream, before the stream reaches the DV Video Decoder filter. This can be helpful for processor-intensive tasks, such as real-time transcoding.

Methods in Vtable Order

IUnknown methodsDescription
QueryInterfaceRetrieves pointers to supported interfaces.
AddRefIncrements the reference count.
ReleaseDecrements the reference count.
IDVSplitter methodsDescription
DiscardAlternateVideoFramesDiscards half of the frames in the video stream.

IDVSplitter::DiscardAlternateVideoFrames

IDVSplitter Interface

Discards half of the frames in the video stream. For NTSC, the frame rate is reduced from 30 frames per second (fps) to 15 fps. For PAL, the frame rate is reduced from 25 fps to 12.5 fps.

Syntax

HRESULT DiscardAlternateVideoFrames(
    int nDiscard
);

Parameters

nDiscard
[in] Flag that specifies whether to discard frames. If the value is non-zero, the filter discards alternate frames. If the value is zero, the filter delivers every frame.

Return Value

Returns an HRESULT value. Possible values include those shown in the following table.

S_OKSuccess.
E_UNEXPECTEDFilter is paused or running.