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            SECTION 4.5                                                                        Color Spaces




                      TABLE 4.16 Additional entries specific to an ICC profile stream dictionary
KEY               TYPE        VALUE

N                 integer     (Required) The number of color components in the color space described by the ICC
                              profile data. This number must match the number of components actually in the ICC
                              profile. As of PDF 1.4, N must be 1, 3, or 4.

Alternate         array or    (Optional) An alternate color space to be used in case the one specified in the stream
                  name        data is not supported (for example, by applications designed for earlier versions of
                              PDF). The alternate space may be any valid color space (except a Pattern color space)
                              that has the number of components specified by N. If this entry is omitted and the ap-
                              plication does not understand the ICC profile data, the color space used is
                              DeviceGray, DeviceRGB, or DeviceCMYK, depending on whether the value of N is 1, 3,
                              or 4, respectively.
                              Note: There is no conversion of source color values, such as a tint transformation, when
                              using the alternate color space. Color values within the range of the ICCBased color space
                              might not be within the range of the alternate color space. In this case, the nearest values
                              within the range of the alternate space are substituted.

Range             array       (Optional) An array of 2 × N numbers [ min0 max0 min1 max1 … ] specifying the min-
                              imum and maximum valid values of the corresponding color components. These val-
                              ues must match the information in the ICC profile. Default value:
                              [ 0.0 1.0 0.0 1.0 … ].

Metadata          stream      (Optional; PDF 1.4) A metadata stream containing metadata for the color space (see
                              Section 10.2.2, “Metadata Streams”).

            The ICC specification is an evolving standard. Table 4.17 shows the versions of
            the ICC specification on which the ICCBased color spaces supported by PDF ver-
            sions 1.3 and later are based. (Earlier versions of the ICC specification are also
            supported.)

                     TABLE 4.17 ICC specification versions supported by ICCBased color spaces
            PDF VERSION      ICC SPECIFICATION VERSION

            1.3              3.3

            1.4              ICC.1:1998-09 and its addendum ICC.1A:1999-04

            1.5              ICC.1:2001-12

            1.6              ICC.1:2003-09

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