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MPEG2VIDEOINFO Structure

 
Microsoft DirectShow 9.0

MPEG2VIDEOINFO Structure

The MPEG2VIDEOINFO structure describes an MPEG-2 video stream.

Syntax

typedef struct tagMPEG2VIDEOINFO {
    VIDEOINFOHEADER2    hdr;
    DWORD               dwStartTimeCode;   
    DWORD               cbSequenceHeader;     
    DWORD               dwProfile;     
    DWORD               dwLevel;            
    DWORD               dwFlags;            
    DWORD               dwSequenceHeader[1];     
} MPEG2VIDEOINFO;

Members

hdr

VIDEOINFOHEADER2 structure.

dwStartTimeCode

25-bit group-of-pictures (GOP) time code at start of data. This field is not used for DVD.

cbSequenceHeader

Length of the sequence header, in bytes. For DVD, set this field to zero. The sequence header is given in the dwSequenceHeader field.

dwProfile

Specifies the MPEG-2 profile as an AM_MPEG2Profile enumeration type.

dwLevel

Specifies the MPEG-2 level as an AM_MPEG2Level enumeration type.

dwFlags

Flag indicating preferences. Set one or a combination of the following values.

Flag Description
AMMPEG2_DoPanScan (0x00000001) If this flag is set, the MPEG-2 video decoder should crop the output image based on pan-scan vectors in picture_display_extension and change the picture aspect ratio to 4x3. The VMR should not receive a 16x9 sample with this flag. A simple implementation might alter the source rectangle to indicate a 540 wide source region with a left edge equal to the display offset in the picture_display_extension.
AMMPEG2_DVDLine21Field1 (0x00000002) If set, the MPEG-2 decoder must be able to produce an output pin for DVD style closed-captioned data found in the Group Of Pictures (GOP) layer of field 1.
AMMPEG2_DVDLine21Field2 (0x00000004) If set, the MPEG-2 decoder must be able to produce an output pin for DVD style closed-captioned data found in the GOP layer of field 2.
AMMPEG2_SourceIsLetterboxed (0x00000008) If set, indicates that black bars have been encoded in the top and bottom of the video.
AMMPEG2_FilmCameraMode (0x00000010) If set, indicates "film mode" used for the 625/50 (line/field) content. If cleared, indicates that "camera mode" was used.
AMMPEG2_LetterboxAnalogOut (0x00000020) If set and this stream is sent to an analog output, it should be letterboxed. Streams sent to VGA should be letterboxed only by renderers.
AMMPEG2_DSS_UserData (0x00000040) If set, the MPEG-2 decoder must process DSS style user data.
AMMPEG2_DVB_UserData (0x00000080) If set, the MPEG-2 decoder must process DVB style user data.
AMMPEG2_27MhzTimebase (0x00000100) If set, the PTS, DTS timestamps advance at 27MHz rather than 90KHz.
AMMPEG2_WidescreenAnalogOut (0x00000200) If set and this stream is sent to an analog output, it should  be in widescreen format (4x3 content should be centered on a 16x9 output). Streams sent to VGA should be widescreened only by renderers.

Set undefined flags to zero or connection will be rejected. For more information on how to use these flags, see MPEG Decoder Preprocessing Transformations.

dwSequenceHeader

Start of an array that contains the sequence header, including quantization matrices and the sequence extension, if required.  This field is typed as DWORD array to enforce 32-bit alignment. The size of the array, in bytes, is given in the cbSequenceHeader member.

Remarks

The BITMAPINFOHEADER structure contained in the VIDEOINFOHEADER2 structure (hdr) cannot be followed by any pallette entries or color masks, because this structure is immediately followed by the dwStartTimeCode member.

Requirements

Header: Dvdmedia.h

See Also