IDvdControl2::SelectVideoModePreference
| Microsoft DirectShow 9.0 |
IDvdControl2::SelectVideoModePreference
The SelectVideoModePreference method sets the specified video mode display (wide screen, letterbox, or pan-scan) for playback.
Syntax
HRESULT SelectVideoModePreference( ULONG ulPreferredDisplayMode );
Parameters
ulPreferredDisplayMode
[in] Value that specifies the new display mode for DVD content. Member of the DVD_PREFERRED_DISPLAY_MODE enumeration.
Return Values
Returns one of the following values.
| Return code | Description |
| S_OK | Success. |
| E_INVALIDARG | Invalid argument. |
| VFW_E_DVD_INVALIDDOMAIN | Invalid domain. |
| VFW_E_DVD_OPERATION_INHIBITED | UOP control prohibits the operation. |
Remarks
This method changes the default video window's aspect ratio and can also specify a default aspect ratio conversion mechanism.
For anamorphic 16 x 9 source video, formed by stretching the 720 x 480 source video to a 16 x 9 aspect ratio.
Widescreen The 16 x 9 source video should be placed and stretched into the largest 16 x 9 area of the client output window. The highlights are relative to the inside of the 16 x 9 area. Black bars should be added to either the top/bottom or to the sides to maintain a 16 x 9 area.
Pan Scan The video shown is computed by taking a 4 x 3 subwindow from the stretched 16 x 9 video (the horizontal offset is provided in the MPEG-2 video's window's offset). The 4 x 3 subwindow is placed into the largest 4 x 3 area of the output client window. The highlight's coordinates are relative to the 4 x 3 output window (and have no relationship to the source 16 x 9 video). Black bars should be added to either the top/bottom or to the sides to maintain a 4 x 3 area.
Letterbox A 4 x 3 display area is formed by taking the largest 4 x 3 area of the output client window. Black bars should be added to either the top/bottom or to the sides to maintain a 4 x 3 area. The source 16 x 9 video is placed in the largest 16 x 9 subwindow inside of the 4 x 3 subwindow. Black bars should be added to the top and bottom of the subwindow to maintain a 16 x 9 area. The highlight's coordinates are relative to the 4 x 3 subwindow (and have no relationship to the source 16 x 9 video). It is technically possible for a disk to specify a highlight that lies outside of the 16 x 9 area (but still in the 4 x 3 window).
For 4 x 3 video, the video is placed in the largest 4 x 3 output area of the output client window. Black bars should be added to either the top/bottom or to the sides to maintain a 4 x 3 area.
The following table shows the Annex J command name to which this method name corresponds, and the domains in which this method is valid.
| Annex J Command Name | Valid Domains |
| Video_Presentation_Mode_Change | DVD_DOMAIN_VideoManagerMenu DVD_DOMAIN_VideoTitleSetMenu DVD_DOMAIN_Title DVD_DOMAIN_Stop |
Requirements
Header: Declared in Strmif.h; include Dshow.h.
Library: Use Strmiids.lib.
See Also