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DVD_PREFERRED_DISPLAY_MODE Enumeration

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Microsoft DirectShow 9.0

DVD_PREFERRED_DISPLAY_MODE Enumeration

Indicates the user's preferred window aspect ratio and conversion method.

Syntax

  typedef enum tagDVD_PREFERRED_DISPLAY_MODE {
    DISPLAY_CONTENT_DEFAULT = 0,
    DISPLAY_16x9 = 1,
    DISPLAY_4x3_PANSCAN_PREFERRED = 2, 
    DISPLAY_4x3_LETTERBOX_PREFERRED = 3
} DVD_PREFERRED_DISPLAY_MODE;

Members

DISPLAY_CONTENT_DEFAULT

Use the default window size and content type.

DISPLAY_16x9

Use a 16 x 9 window.

DISPLAY_4x3_PANSCAN_PREFERRED

Use a 4 x 3 window and convert to pan-scan , if possible.

DISPLAY_4x3_LETTERBOX_PREFERRED

Use a 4 x 3 window and convert to letterbox, if possible.

Remarks

DVD_PREFERRED_DISPLAY_MODE indicates the user's preferred window aspect ratio and preferred method of conversion of 16 x 9 content to a 4 x 3 window aspect ratio. Pan-scan and letterboxing are the two conversion methods. Displaying a video at the largest possible size inside the display window without any cropping or stretching is called displaying in letterbox format. Pan-scan is specifically cropping a 16 x 9 video for display in a 4 x 3 window using parameters defined by the video author.

This enumerated type indicates a preference of conversion mechanisms because some content can only be displayed using one of these methods. Content that is 4 x 3 is always converted to a 16 x 9 window by using sideboxing, where black bars are added to the right and left sides of the display instead of the top and bottom of the display as in the 16 x 9 to 4 x 3 conversion using letterboxing.

The following table shows the conversion method used between the actual content type listed in the first column, and the user display preference setting, indicated by one of the other columns.

Actual content type 16 x 9 4 x 3 pan-scan 4 x 3 letterbox
4 x 3 Sideboxing None None
16 x 9 letterbox only None Letterbox Letterbox
16 x 9 pan-scan only None Pan-scan Pan-scan
16 x 9 pan-scan or letterbox None Pan-scan Letterbox

The native window size used is always the user's preferred size.

Requirements

  Header: Dshow.h

See Also