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:
| Flag | Description |
|---|---|
| KS_INTERLACE_IsInterlaced | Indicates an interlace stream. If 0, then the other KS_INTERLACE_Xxx bits are irrelevant. |
| KS_INTERLACE_1FieldPerSample | Indicates one field per media sample. If zero, indicates two fields per media sample. |
| KS_INTERLACE_Field1First | Indicates that Field 1 is first. If zero, indicates that Field 2 is first. Top field in PAL is Field 1, top field in NTSC is Field 2. |
| KS_INTERLACE_UNUSED | Unused |
| KS_INTERLACE_FieldPatternMask | Indicates the bits used to specify field pattern. |
| KS_INTERLACE_FieldPatField1Only | Indicates that a stream never contains a Field 2. |
| KS_INTERLACE_FieldPatField2Only | Indicates that a stream never contains a Field 1. |
| KS_INTERLACE_FieldPatBothRegular | Indicates that there will be a Field 2 for every Field 1. |
| KS_INTERLACE_FieldPatBothIrregular | Indicates a random pattern of Field 1s and Field 2s. |
| KS_INTERLACE_DisplayModeMask | Invalid for video capture. |
| KS_INTERLACE_DisplayModeBobOnly | Invalid for video capture. |
| KS_INTERLACE_DisplayModeWeaveOnly | Invalid for video capture. |
| KS_INTERLACE_DisplayModeBobOrWeave | Invalid for video capture. |
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.
| Value | Description |
|---|---|
| AMCONTROL_USED | Indicates the dwControlFlags flags are used. |
| AMCONTROL_PAD_TO_4x3 | The image should be padded and displayed in a 4 x 3 area. |
| AMCONTROL_PAD_TO_16x9 | The image should be padded and displayed in a 16 x 9 area. |
| AMCONTROL_COLORINFO_PRESENT | Additional color information is contained in the upper 24 bits of the dwControlFlags field. |
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
| Requirement | Value |
|---|---|
| Header | ksmedia.h (include Ksmedia.h) |