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WIA_IPS_XEXTENT

The WIA_IPS_XEXTENT property contains the current width, in pixels, of a selected image to acquire.

Property Type: VT_I4

Valid Values: WIA_PROP_RANGE

Access Rights: Read/write

Remarks

An application sets the WIA_IPS_XEXTENT property to mark the upper-left corner (that is, the width) of the selection area to acquire. The minidriver creates and maintains this property.

WIA_IPS_XEXTENT is required for all image acquisition enabled items and child items of these items; this property is not available for storage items or stored image items.

When a fixed page size is set, the driver has to set the WIA_IPS_XEXTENT, WIA_IPS_XPOS, WIA_IPS_YEXTENT, and WIA_IPS_YPOS properties to match the page size dimensions and a "0" origin. For center document alignment, the driver has to set WIA_IPS_XPOS to ((scan area width - document width) / 2) * resolution [DPI]) and WIA_IPS_YPOS to ((scan area height - document height) / 2) * resolution [DPI]).

When the origin or one extent is changed, the driver has to update the WIA_IPS_PAGE_SIZE property to CUSTOM_SIZE and the WIA_IPS_PAGE_WIDTH and WIA_IPS_PAGE_HEIGHT properties to match the scan area extents. Orientation and rotation should not affect these properties, unless an orientation change (not a rotation change) renders the origin or one extent outside of the available document scan area.

A driver must also to update the WIA_IPS_XEXTENT, WIA_IPS_XPOS, WIA_IPS_YEXTENT, and WIA_IPS_YPOS properties when WIA_IPS_XRES and WIA_IPS_YRES are changed.

Note   Flatbed and Film child items must support only the WIA_IPS_XEXTENT, WIA_IPS_XPOS, WIA_IPS_XRES, WIA_IPS_YEXTENT, WIA_IPS_YPOS, and WIA_IPS_YRES properties. All other properties, required or optional for their parent (the base Flatbed or Film items), are only optional for these items. The only exceptions are the WIA_IPA_ITEM_Xxx properties, which are required for all items.

Requirements

Header: wiadef.h (include Wiadef.h)

See also

WIA_IPA_PIXELS_PER_LINE

WIA_IPS_PAGE_HEIGHT

WIA_IPS_PAGE_SIZE

WIA_IPS_PAGE_WIDTH

WIA_IPS_XEXTENT

WIA_IPS_XPOS

WIA_IPS_XRES

WIA_IPS_YEXTENT

WIA_IPS_YPOS

WIA_IPS_YRES