CHAPTER 4
254
Graphics
PDF VERSION
ICC SPECIFICATION VERSION
1.7
ICC.1:2004-10
PDF producers and consumers should follow these guidelines:
•
A consumer that supports a given PDF version is required to support ICC pro-
files conforming to the corresponding version (and earlier versions) of the ICC
specification, as described above. It may optionally support later ICC versions.
•
For the most predictable and consistent results, a producer of a given PDF ver-
sion should embed only profiles conforming to the corresponding version of
the ICC specification.
•
A PDF producer may embed profiles conforming to a later ICC version, with
the understanding that the results will vary depending on the capabilities of the
consumer. The consumer might process the profile while ignoring newer
features, or it might fail altogether to process the profile. Therefore, it is recom-
mended that the producer provide an alternate color space (
Alternate
entry in
the
ICCBased
color space dictionary) containing a profile that is appropriate for
the PDF version.
PDF supports only the profile types shown in Table 4.18; other types may be sup-
ported in the future. (In particular, note that
XYZ
and 16-bit
L*a*b*
profiles are
not supported.) Each of the indicated fields must have one of the values listed for
that field in the second column of the table. (Profiles must satisfy
both
the criteria
shown in the table.) The terminology is taken from the ICC specifications.
TABLE 4.18 ICC profile types
HEADER FIELD
REQUIRED VALUE
deviceClass
icSigInputClass ('scnr')
icSigDisplayClass ('mntr')
icSigOutputClass ('prtr')
icSigColorSpaceClass ('spac')
icSigGrayData ('GRAY')
icSigRgbData ('RGB ')
icSigCmykData ('CMYK')
icSigLabData ('Lab ')
colorSpace