cpthsv (1) - Linux Manuals
cpthsv: modify hue, saturation and colour value of GMT colour palette tables.
NAME
cpthsv - modify hue, saturation and colour value of GMT colour palette tables.
SYNOPSIS
-
cpthsv -T
transform [-h] [-o file] [-v] [-V] [file]
DESCRIPTION
The program will read from stdin if a file is not specified as the final argument, and write to stdout if the -o option is not specified.
The hue value is taken to be between 0 and 360, while the saturation and value components are taken to be between 0 and 1,
OPTIONS
-h, --help
- Brief help.
-o, --output file
- Write the output to file, rather than stdout.
-T, --transform string
-
Specify a transformation to perform. One of
h,
s
or
v
followed by a
number
and optional
operation. The effect of the number depends on the operation: one of
x
(multiply by
number),
%
(scale by percentage) or
+/-
(add or subtract value). An RGB colour with saturation 0.5 would be transformed to one with saturation 0.55 by applying
s1.1x
or
s110%
or
s0.05+. If the operator is not given then
%
is assumed.
Transforms which take colours outside the HSV colour-space are permitted, the result is truncation (eg, increasing a saturation of 0.8 with s0.3+ results in a saturation of 1.0). The exception is hue, which is taken modulo 360.
Multiple transforms can be applied by separating transforms with commas. This is to be preferred over multiple calls to the program since the conversion between colour-spaces is necessarily lossy. Multiple trnsformations are applied in the order given in the argument.
-v, --verbose
- Verbose operation.
-V, --version
- Version information.
EXAMPLE
Lighten by 10% and desaturate by 20%:
-
cpthsv -v -T s80,v110 -o new.cpt old.cpt