tagKS_VIDEOINFOHEADER structure

The KS_VIDEOINFOHEADER structure describes the bitmap and color information for a video stream.

Syntax

typedef struct tagKS_VIDEOINFOHEADER {
  RECT                rcSource;
  RECT                rcTarget;
  DWORD               dwBitRate;
  DWORD               dwBitErrorRate;
  REFERENCE_TIME      AvgTimePerFrame;
  KS_BITMAPINFOHEADER bmiHeader;
} KS_VIDEOINFOHEADER, *PKS_VIDEOINFOHEADER;

Members

AvgTimePerFrame

Specifies the average time per frame, in 100-nanosecond units.

bmiHeader

Describes a KS_BITMAPINFOHEADER structure that contains color and dimension information about the video image bitmap.

dwBitErrorRate

Specifies a value that indicates the video stream's data error rate, in bit errors per second.

dwBitRate

Specifies a value that indicates the video stream's approximate data rate, in bits per second.

rcSource

Specifies a clipping rectangle that selects the portion of the active video signal to use.

rcTarget

Specifies a rectangle that defines the target destination video window.

Remarks

To describe a video stream with bob or weave settings, use KS_VIDEOINFOHEADER2.

The KS_VIDEOINFOHEADER structure is identical to the Microsoft DirectShow VIDEOINFOHEADER structure.

A source filter can request that the sink filter take only a section of the video by providing values that effectively define a clipping rectangle in the rcSource member. However, if the sink filter does not check for the clipping rectangle on connection, the sink filter simply renders all of the video, effectively ignoring any clipping information passed from the source filter to the sink filter.

Ideally, a sink filter checks rcSource and if the sink filter does not support image extraction, and the rectangle is not empty, then it rejects the connection. A filter should use the Win32 function SetRectEmpty to reset a rectangle to all zeros (and set IsRectEmpty to later check the rectangle).

The rcTarget member specifies the destination rectangle for the video. Most source filters set this member to all zeros. A downstream filter can request that the video be placed in a particular area of the buffers that it supplies. In this case, it calls the Win32 function QueryAccept with a nonempty target.

Requirements

   
Header ksmedia.h (include Ksmedia.h)

See Also

KS_VIDEOINFOHEADER2

KS_BITMAPINFOHEADER

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