TIFF 6.0 Specification
Final—June 3, 1992
DotRange
Tag
= 336 (150.H)
Type = BYTE or SHORT
N
= 2, or 2*SamplesPerPixel
The component values that correspond to a 0% dot and 100% dot. DotRange[0]
corresponds to a 0% dot, and DotRange[1] corresponds to a 100% dot.
If a DotRange pair is included for each component, the values for each component
are stored together, so that the pair for Cyan would be first, followed by the pair
for Magenta, and so on.
Use of multiple dot ranges is, however, strongly discour-
aged in the interests of simplicity and compatibility with ANSI IT8 standards.
A number of prepress systems like to keep some “headroom” and “footroom” on
both ends of the range. What to do with components that are less than the 0% aim
point or greater than the 100% aim point is not specified and is application-depen-
dent.
It is strongly recommended that a CMYK TIFF writer not attempt to use this field
to reverse the sense of the pixel values so that smaller values mean more ink in-
stead of less ink. That is, DotRange[0] should be less than DotRange[1].
DotRange[0] and DotRange[1] must be within the range [0, (2**BitsPerSample) -
1].
Default: a component value of 0 corresponds to a 0% dot, and a component value
of 255 (assuming 8-bit pixels) corresponds to a 100% dot. That is, DotRange[0] =
0 and DotRange[1] = (2**BitsPerSample) - 1.
TargetPrinter
Tag
= 337 (151.H)
Type = ASCII
N
= any
A description of the printing environment for which this separation is intended.
History
This Section has been expanded from earlier drafts, with the addition of the
InkSet, InkNames, NumberOfInks, DotRange,
and
TargetPrinter,
but is
backward-compatible with earlier draft versions.
Possible future enhancements: definition of the characterization information so
that the CMYK data can be retargeted to a different printing environment and so
that display on a CRT or proofing device can more accurately represent the color.
ANSI IT8 is working on such a proposal.
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