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                                                       274
             CHAPTER 4                                                                        Graphics




                               TABLE 4.22 Entries in a DeviceN process dictionary
KEY             TYPE            VALUE

ColorSpace      name or         (Required) A name or array identifying the process color space, which may be any
                array           device or CIE-based color space. If an ICCBased color space is specified, it must
                                provide calibration information appropriate for the process color components
                                specified in the names array of the DeviceN color space.

Components      array           (Required) An array of component names that correspond, in order, to the com-
                                ponents of the process color space specified in ColorSpace. For example, an RGB
                                color space must have three names corresponding to red, green, and blue. The
                                names may be arbitrary (that is, not the same as the standard names for the color
                                space components) and must match those specified in the names array of the
                                DeviceN color space, even if all components are not present in the names array.


                           TABLE 4.23 Entries in a DeviceN mixing hints dictionary
KEY               TYPE            VALUE

Solidities        dictionary      (Optional) A dictionary specifying the solidity of inks to be used in blending
                                  calculations when used as an alternative to the tint transformation function.
                                  For each entry, the key is a colorant name, and the value is a number between
                                  0.0 and 1.0. This dictionary need not contain entries for all colorants used in
                                  this color space; it may also include additional colorants not used by this color
                                  space.
                                  A value of 1.0 simulates an ink that completely covers the inks beneath; a value
                                  of 0.0 simulates a transparent ink that completely reveals the inks beneath. An
                                  entry with a key of Default specifies a value to be used by all components in the
                                  associated DeviceN color space for which a solidity value is not explicitly pro-
                                  vided. If Default is not present, the default value for unspecified colorants is
                                  0.0; applications may choose to use other values.
                                  If this entry is present, PrintingOrder must also be present.

PrintingOrder     array           (Required if Solidities is present) An array of colorant names, specifying the or-
                                  der in which inks are laid down. Each component in the names array of the
                                  DeviceN color space must appear in this array (although the order is unrelated
                                  to the order specified in the names array). This entry may also list colorants
                                  unused by this specific DeviceN instance.

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