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DV Splitter Filter

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[The feature associated with this page, DirectShow, is a legacy feature. It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation. Those features have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer, IMFMediaEngine and Audio/Video Capture in Media Foundation instead of DirectShow, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

This filter splits an interleaved digital video (DV) stream into its component video and audio streams.

Label Value
Filter Interfaces IBaseFilter, IDVSplitter
Input Pin Media Types MEDIATYPE_Interleaved, MEDIASUBTYPE_dvsd, FORMAT_DvInfo
Input Pin Interfaces IMemInputPin, IPin, IQualityControl
Output Pin Media Types Video: MEDIATYPE_Video, FORMAT_DvInfo
Audio: MEDIATYPE_Audio, MEDIASUBTYPE_PCM, FORMAT_WaveFormatEx
Output Pin Interfaces IMediaPosition, IMediaSeeking, IPin, IQualityControl
Filter CLSID CLSID_DVSplitter
Property Page CLSID No property page.
Executable qdv.dll
Merit MERIT_NORMAL
Filter Category CLSID_LegacyAmFilterCategory

Remarks

DV frames contain audio and video in the same frame. The DV Splitter filter extracts the audio data and delivers it as one or two audio streams, from the audio output pins. The original DV frame is delivered from the video output pin, as a video frame. The media type on the video frame is changed from MEDIATYPE_Interleaved to MEDIATYPE_Video, but otherwise the data is not modified. The media type is changed to signal that the audio data into the frame should be ignored. The DV Splitter does not set a media time on its output samples; if you are writing a downstream filter that requires the media times, then you can derive the times from the frame count.

Only one output pin at a time exposes the IMediaPosition and IMediaSeeking interfaces.

The DV Splitter filter can accept dynamic format changes in the audio stream. However, if the AVI Mux filter is downstream, it will reject the format change. If this happens, the DV Splitter stops producing an audio stream. This limitation only affects type-2 file capture. For type-1 files, the interleaved stream is not split in the first place. For preview, there is no AVI Mux filter downstream.

If the DV source is a live camera, there is normally no reason for the audio format to change. However, the format might change if you transmit from a VTR tape that contains several heterogeneous sources.

Each DV frame contains metadata, in addition to the audio and video data. This metadata can change from frame to frame. Applications can parse the metadata by examining either the input samples or the video output samples. However, DirectShow does not provide any direct support for parsing DV metadata. Consult IEC 61834-4 for more information.

DirectShow Filters

Digital Video in DirectShow