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Property Validation for RAW Format Transfers

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The driver must validate the WIA property settings prior to a RAW format data transfer. The WIA properties must be set as follows:

WIA_IPS_XPOS, WIA_IPS_YPOS
These properties are set the same for RAW as they are for other image formats. These properties contain the coordinates, in pixels, of the upper-left corner of the selected image

WIA_IPS_XRES, WIA_IPS_YRES
These properties are set the same for RAW as they are for other image formats. These properties contain the current horizontal and vertical (respectively) resolution, in pixels per inch, for the device

WIA_IPS_XEXTENT, WIA_IPS_YEXTENT
These properties are set by the application and are read by and updated by the driver. Because the properties might be changed from their original values, the application must read the value stored in these properties when it processes the RAW stream.

WIA_IPA_DEPTH
This property contains the number of bits per pixel. The driver sets the value of this property when the application sets WIA_IPA_FORMAT to WiaImgFmt_RAW. The sum of all of the entries in the WIA_IPA_RAW_BITS_PER_CHANNEL property must equal the number stored in the WIA_IPA_DEPTH property. WIA_IPA_DEPTH is writable if the driver supports multiple configurations. For example, for a driver that supports 32 bits per pixel and 48 bits per pixel configurations, the application can choose one setting, and the driver should set WIA_IPA_RAW_BITS_PER_CHANNEL and the associated properties accordingly.

WIA_IPA_RAW_BITS_PER_CHANNEL
This property is set by the driver in response to a value of WiaImgFmt_RAW in the WIA_IPA_FORMAT property and is updated when WIA_IPA_DATATYPE is changed. All entries for WIA_IPA_RAW_BITS_PER_CHANNEL must equal the number of bits per pixel stored in WIA_IPA_DEPTH.

WIA_IPA_CHANNELS_PER_PIXEL
This property is set by the driver to the number of channels per pixel of the selected RAW subtype in WIA_IPA_DATATYPE.

WIA_IPA_DATATYPE
When WIA_IPA_FORMAT is set to WiaImgFmt_RAW, the driver sets this property to a default value. The driver also determines a list of allowable values from which the application can select to change the default value. The WIA_IPA_DATATYPE default value is selected by the driver; it can be any value that the device allows.

WIA_IPA_BYTES_PER_LINE
Must be updated by the minidriver according to the WIA_IPA_FORMAT and WIA_IPA_DATATYPE settings.

WIA_IPA_ITEM_SIZE
Must be zero.