DVD Subpicture Property Set

DVD Subpicture properties control the color, contrast, and output of the subpicture display.

The following information presents the necessary constants and data types to use for this property set in calls to IKsPropertySet methods. It provides values for the GUID (guidPropSet), property ID (dwPropID), and property data type (pPropData) parameters.

Property Set GUID: AM_KSPROPSETID_DvdSubPic

Property ID	Data type used by the specified property
AM_PROPERTY_DVDSUBPIC_COMPOSIT_ON	AM_PROPERTY_COMPOSIT_ON
AM_PROPERTY_DVDSUBPIC_HLI	AM_PROPERTY_SPHLI
AM_PROPERTY_DVDSUBPIC_PALETTE	AM_PROPERTY_SPPAL

The following list provides the Subpicture property IDs and descriptions.

AM_PROPERTY_DVDSUBPIC_COMPOSIT_ON

Set-only property that enables or disables subpicture display. DirectShow defines the AM_PROPERTY_COMPOSIT_ON Boolean data type for this property, as well as PAM_PROPERTY_COMPOSIT_ON as a pointer to this data type. TRUE indicates display the subpicture, FALSE indicates disable it. See the WDM portion of the Windows 98 DDK for more information.

AM_PROPERTY_DVDSUBPIC_HLI

Set-only property that specifies a rectangle of subpicture or screen whose color or contrast will be changed. Data type is AM_PROPERTY_SPHLI.

The AM_PROPERTY_DVDSUBPIC_HLI property is set-only. It specifies a rectangle of subpicture or screen whose color or contrast will be changed. This differs from the DVD-Video specification, in that the Microsoft DVD navigator parses all button and keyboard information and passes only one highlight rectangle to the subpicture decoder at any given time. As a result, highlight information is sent to the decoder more often than it is present in the DVD stream.

The highlight information arrives asynchronously to the data stream. The decoder uses the highlight Start and End time stamps to correlate the highlight information to the relevant subpicture information, if any. If the decoder has not received any subpicture stream information for the requested time stamps, the decoder assumes that the highlight information is stand-alone and does not apply to a subpicture. In this case, the decoder assumes the color and contrast information is all the same color.

The data is not entirely in DVD disc format. Microsoft provides an additional structure of type AM_PROPERTY_SPHLI that is passed as the parameter to this property. This structure describes the currently selected button from the DVD highlight information.

The DVD navigator processes all keystroke information and sends new highlight information each time a button state changes. The information describes only one mode of one button at a time. It includes a display rectangle in pixel coordinates of the screen, or a display of the subpicture, if present. The structure also contains color and contrast information, but only for the present state of the currently selected button. The format is defined in the DVD specification.

Highlight information contains Start and End time stamps. These are in the same units as other time stamps, with two exceptions: A Start time stamp of 0xFFFFFFFF means the highlight property is effective upon receipt, and an End time stamp of 0xFFFFFFFF means the highlight property is valid until next highlight received.

The HLISS field is as defined in the DVD specification. A value of zero indicates that all highlights are invalid and the decoder should disable all highlights.

AM_PROPERTY_DVDSUBPIC_PALETTE

Sets the palette for a subpicture. Data type is AM_PROPERTY_SPPAL.

Use the IKsPropertySet interface to set, retrieve, and query for support of these properties.

This property set uses the following data types.

Data type	Description
AM_COLCON	Specifies the color contrast. Substructure of the AM_PROPERTY_SPHLI structure.
AM_DVD_YUV	Specifies DVD YUV subpicture data. Substructure of the AM_PROPERTY_SPPAL structure.
AM_PROPERTY_COMPOSIT_ON	Boolean data used by the AM_PROPERTY_DVDSUBPIC_COMPOSIT_ON property.
AM_PROPERTY_SPHLI	Describes the currently selected button from the DVD highlight information.
AM_PROPERTY_SPPAL	Specifies the DVD subpicture palette.

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AM_COLCON

DVD Subpicture Property Set

Indicates the color contrast description from the DVD highlight (HLI) structure.

 typedef struct _AM_COLCON {
    UCHAR emph1col:4;
    UCHAR emph2col:4;
    UCHAR backcol:4;
    UCHAR patcol:4;
    UCHAR emph1con:4;
    UCHAR emph2con:4;
    UCHAR backcon:4;
    UCHAR patcon:4;
} AM_COLCON, *PAM_COLCON;

Members

emph1col

Emphasis color 1.

emph2col

Emphasis color 2.

backcol

Background color.

patcol

Pattern color.

emph1con

Emphasis contrast 1.

emph2con

Emphasis contrast 2.

backcon

Background contrast.

patcon

Pattern contrast.

Remarks

This structure is contained within the AM_PROPERTY_SPHLI structure.

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AM_DVD_YUV

DVD Subpicture Property Set

DVD YUV subpicture data.

 typedef struct _AM_DVD_YUV {
    UCHAR   Reserved;
    UCHAR   Y;
    UCHAR   U;
    UCHAR   V;
} AM_DVD_YUV, *PAM_DVD_YUV;

Members

Reserved

Reserved.

Y

Y color data.

U

U color data.

V

V color data.

Remarks

This structure is contained within the AM_PROPERTY_SPPAL structure.

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AM_PROPERTY_SPHLI

DVD Subpicture Property Set

Describes the currently selected button from the DVD highlight information.

 typedef struct _AM_PROPERTY_SPHLI {
    USHORT  HLISS;      
    USHORT  Reserved;
    ULONG   StartPTM; 
    ULONG   EndPTM;  
    USHORT  StartX;
    USHORT  StartY;
    USHORT  StopX;
    USHORT  StopY;
    AM_COLCON  ColCon; 
} AM_PROPERTY_SPHLI, *PAM_PROPERTY_SPHLI;

Members

HLISS

Highlight status of current selection.

Reserved

Reserved for internal use. Do not use or set.

StartPTM

Start presentation time divided by 90,000.

EndPTM

End presentation time divided by 90,000.

StartX

Start x-coordinate pixel of the current highlight button.

StartY

Start y-coordinate pixel of the current highlight button.

StopX

Ending x-coordinate pixel of the current highlight button.

StopY

Ending y-coordinate pixel of the current highlight button.

ColCon

Color contrast description of type AM_COLCON.

Remarks

The AM_PROPERTY_DVDSUBPIC_HLI property uses this structure.

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AM_PROPERTY_SPPAL

DVD Subpicture Property Set

Specifies the DVD subpicture palette.

 typedef struct _AM_PROPERTY_SPPAL {
    AM_DVD_YUV sppal[16];
} AM_PROPERTY_SPPAL, *PAM_PROPERTY_SPPAL;

Members

sppal

Array of 16 YUV elements that correspond to the 4-bit color numbers requested within the subpicture command stream. The YUV elements are of type AM_DVD_YUV.

Remarks

The AM_PROPERTY_DVDSUBPIC_PALETTE property uses this structure.

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