KS_VIDEOINFOHEADER2 structure (ksmedia.h)

The KS_VIDEOINFOHEADER2 structure describes the details of a video stream, including bob or weave settings, copy protection, and pixel aspect ratio.

Syntax

typedef struct tagKS_VIDEOINFOHEADER2 {
  RECT                rcSource;
  RECT                rcTarget;
  DWORD               dwBitRate;
  DWORD               dwBitErrorRate;
  REFERENCE_TIME      AvgTimePerFrame;
  DWORD               dwInterlaceFlags;
  DWORD               dwCopyProtectFlags;
  DWORD               dwPictAspectRatioX;
  DWORD               dwPictAspectRatioY;
  union {
    DWORD dwControlFlags;
    DWORD dwReserved1;
  };
  DWORD               dwReserved2;
  KS_BITMAPINFOHEADER bmiHeader;
} KS_VIDEOINFOHEADER2, *PKS_VIDEOINFOHEADER2;

Members

rcSource

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

rcTarget

Specifies a rectangle that indicates what part of the target buffer to use.

dwBitRate

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

dwBitErrorRate

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

AvgTimePerFrame

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

dwInterlaceFlags

Specifies interlace information. Undefined flags must be set to zero, or the connection may be rejected. This member can be set to one or more (logical OR) values that are defined in ksmedia.h:

dwCopyProtectFlags

Specifies a KSCOPYPROTECTRestrictDuplication value (0x00000001) to indicate if duplication of a stream should be restricted. If undefined, specify zero or the connection will be rejected.

dwPictAspectRatioX

Specifies the x dimension of the picture-aspect ratio (for example, 16 for a 16 × 9 display). The value is expressed in inches-by-inches, not pixels-by-pixels.

dwPictAspectRatioY

Specifies the y dimension of the picture aspect ratio (for example, 9 for 16 × 9 display). The value is expressed in inches-by-inches, not pixels-by-pixels.

dwControlFlags

In operating systems prior to Windows Vista, this member was named dwReserved1 and was required to be zero. In Windows Vista, dwReserved1 was combined in a union with a new member named dwControlFlags. If used, dwControlFlags contains a bitwise OR of the flags in the following table.

The AMCONTROL_USED flag provides backward compatibility with older filters. If the AMCONTROL_USED flag is not set, the remaining bits in this field should be ignored. If a filter uses any other flags, it should set the AMCONTROL_USED flag.

The two AMCONTROL_PAD_xxx flags are used by decoders to determine the aspect ratio of the output rectangle.

If the AMCONTROL_COLORINFO_PRESENT flag is set, it means the upper 24 bits of the dwControlFlags field are treated as a DXVA_ExtendedFormat structure.

See the Remarks section later in this topic for more information about dwControlFlags.

dwReserved1

This member is for backward compatibility. See dwControlFlags for more information.

dwReserved2

Reserved for system use. Must be set to zero or the connection will be rejected.

bmiHeader

Indicates a KS_BITMAPINFOHEADER structure that contains color and dimension information for the video image bitmap.

Remarks

To describe a video stream without bob or weave settings, use KS_VIDEOINFOHEADER.

The KS_VIDEOINFOHEADER2 structure is identical to the DirectShow VIDEOINFOHEADER2 structure.

Capture minidrivers that produce video fields (instead of frames) must use the KS_DATARANGE_VIDEO2 structure, which contains the KS_VIDEOINFOHEADER2 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.

If the AMCONTROL_COLORINFO_PRESENT flag is set in the dwControlFlags member, you can cast the dwControlFlags value to a DXVA_ExtendedFormat structure to access the extended color information. For more information, see VIDEOINFOHEADER2.

Requirements

See also

KS_BITMAPINFOHEADER

KS_DATARANGE_VIDEO2

KS_VIDEOINFOHEADER