DVD Subpicture Property Set

[The feature associated with this page, DirectShow, is a legacy feature. It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation. Those features have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer, IMFMediaEngine and Audio/Video Capture in Media Foundation instead of DirectShow, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

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.

Label	Value
Property Set GUID	AM_KSPROPSETID_DvdSubPic

Property ID	Description
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 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. See Remarks.
AM_PROPERTY_DVDSUBPIC_PALETTE	Sets the palette for a subpicture. Data type is AM_PROPERTY_SPPAL.

Remarks

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.

Requirements

Requirement	Value
Header	Dvdmedia.h

See also

Property Sets