Free imager color software for linux

Imager::Color is a Perl module with color handling for Imager.

SYNOPSIS

$color = Imager::Color->new($red, $green, $blue);
$color = Imager::Color->new($red, $green, $blue, $alpha);
$color = Imager::Color->new("#C0C0FF"); # html color specification

$color->set($red, $green, $blue);
$color->set($red, $green, $blue, $alpha);
$color->set("#C0C0FF"); # html color specification

($red, $green, $blue, $alpha) = $color->rgba();
@hsv = $color->hsv(); # not implemented but proposed

$color->info();

if ($color->equals(other=>$other_color)) {
...
}

This module handles creating color objects used by imager. The idea is that in the future this module will be able to handle colorspace calculations as well.

new

This creates a color object to pass to functions that need a color argument.

set

This changes an already defined color. Note that this does not affect any places where the color has been used previously.

rgba

This returns the rgba code of the color the object contains.

info

Calling info merely dumps the relevant colorcode to the log.

equals(other=>$other_color)
equals(other=>$other_color, ignore_alpha=>1)

Compares $self and color $other_color returning true if the color components are the same.

Compares all four channels unless ignore_alpha is set. If ignore_alpha is set only the first three channels are compared.

You can specify colors in several different ways, you can just supply simple values:
simple numeric parameters - if you supply 3 or 4 numeric arguments, you get a color made up of those RGB (and possibly A) components.

a six hex digit web color, either RRGGBB or #RRGGBB
an eight hex digit web color, either RRGGBBAA or #RRGGBBAA.
a 3 hex digit web color, #RGB - a value of F becomes 255.
a color name, from whichever of the gimp Named_Colors file or X rgb.txt is found first. The same as using the name keyword.

You can supply named parameters:

red, green and blue, optionally shortened to r, g and b. The color components in the range 0 to 255.

# all of the following are equivalent
my $c1 = Imager::Color->new(red=>100, blue=>255, green=>0);
my $c2 = Imager::Color->new(r=>100, b=>255, g=>0);
my $c3 = Imager::Color->new(r=>100, blue=>255, g=>0);
hue, saturation and value, optionally shortened to h, s and v, to specify a HSV color. 0 new(hue=>120, value=>1, saturation=>0.5);
web, which can specify a 6 or 3 hex digit web color, in any of the forms #RRGGBB, #RGB, RRGGBB or RGB.
my $c1 = Imager::Color->new(web=>#FFC0C0); # pale red
gray or grey which specifies a single channel, from 0 to 255.
# exactly the same
my $c1 = Imager::Color->new(gray=>128);
my $c1 = Imager::Color->new(grey=>128);
rgb which takes a 3 member arrayref, containing each of the red, green and blue values.
# the same
my $c1 = Imager::Color->new(rgb=>[255, 100, 0]);
my $c1 = Imager::Color->new(r=>255, g=>100, b=>0);
hsv which takes a 3 member arrayref, containting each of hue, saturation and value.
# the same
my $c1 = Imager::Color->new(hsv=>[120, 0.5, 1]);
my $c1 = Imager::Color->new(hue=>120, v=>1, s=>0.5);

gimp which specifies a color from a GIMP palette file. You can specify the filename of the palette file with the palette parameter, or let Imager::Color look in various places, typically "$HOME/gimp-1.x/palettes/Named_Colors" with and without the version number, and in /usr/share/gimp/palettes/. The palette file must have color names.

my $c1 = Imager::Color->new(gimp=>snow);
my $c1 = Imager::Color->new(gimp=>snow, palette=>testimg/test_gimp_pal);

xname which specifies a color from an X11 rgb.txt file. You can specify the filename of the rgb.txt file with the palette parameter, or let Imager::Color look in various places, typically /usr/lib/X11/rgb.txt.

my $c1 = Imager::Color->new(xname=>blue) # usually RGB(0, 0, 255)

builtin which specifies a color from the built-in color table in Imager::Color::Table. The colors in this module are the same as the default X11 rgb.txt file.

my $c1 = Imager::Color->new(builtin=>black) # always RGB(0, 0, 0)

name which specifies a name from either a GIMP palette, an X rgb.txt file or the built-in color table, whichever is found first.

channel0, channel1, etc, each of which specifies a single channel. These can be abbreviated to c0, c1 etc.

channels which takes an arrayref of the channel values.

Optionally you can add an alpha channel to a color with the alpha or a parameter.

These color specifications can be used for both constructing new colors with the new() method and modifying existing colors with the set() method.

gcolor2 is a simple color selector that was originally based on gcolor, ported to use GTK+2, and now has a completely new UI.
Enhancements:
- Improvements include usability / UI enhancements, and sortable columns.

Imager::Filters is an entire image filtering operations.

SYNOPSIS

use Imager;

$img = ...;

$img->filter(type=>autolevels);
$img->filter(type=>autolevels, lsat=>0.2);
$img->filter(type=>turbnoise)

# and lots of others

load_plugin("dynfilt/dyntest.so")
or die "unable to load pluginn";

$img->filter(type=>lin_stretch, a=>35, b=>200);

unload_plugin("dynfilt/dyntest.so")
or die "unable to load pluginn";

$out = $img->difference(other=>$other_img);

Filters are operations that have similar calling interface.

filter

Parameters:

type - the type of filter, see "Types of Filters".

many other possible parameters, see "Types of Filters" below.

Imager::Fountain is a class for building fountain fills suitable for use by the fountain filter.

SYNOPSIS

use Imager::Fountain;
my $f1 = Imager::Fountain->read(gimp=>$filename);
$f->write(gimp=>$filename);
my $f1 = Imager::Fountain->new;
$f1->add(start=>0, middle=>0.5, end=>1.0,
c0=>Imager::Color->new(...),
c1=>Imager::Color->new(...),
type=>$trans_type, color=>$color_trans_type);

Provide an interface to build arrays suitable for use by the Imager fountain filter. These can be loaded from or saved to a GIMP gradient file or you can build them from scratch.

Imager::Engines is a Perl module for programmable transformation operations.

SYNOPSIS

use Imager;

my %opts;
my @imgs;
my $img;
...

my $newimg = $img->transform(
xexpr=>x,
yexpr=>y+10*sin((x+y)/10))
or die $img->errstr;

my $newimg = Imager::transform2(%opts, @imgs)
or die "transform2 failed: $Imager::ERRSTR";

my $newimg = $img->matrix_transform(
matrix=>[ -1, 0, $img->getwidth-1,
0, 1, 0,
0, 0, 1 ]);

transform

The transform() function can be used to generate spatial warps and rotations and such effects. It only operates on a single image and its only function is to displace pixels.

It can be given the operations in postfix notation or the module Affix::Infix2Postfix can be used to generate postfix code from infix code. Look in the test case t/t55trans.t for an example.
transform() needs expressions (or opcodes) that determine the source pixel for each target pixel. Source expressions are infix expressions using any of the +, -, *, / or ** binary operators, the - unary operator, ( and ) for grouping and the sin() and cos() functions. The target pixel is input as the variables x and y.

You specify the x and y expressions as xexpr and yexpr respectively. You can also specify opcodes directly, but thats magic deep enough that you can look at the source code.

GFA Fractal Imager project is a imager which uses a simple visual construction mechanism.
Generalized Finite Automata (GFA) Imager is a simple Java Applet which creates fractal images using an intuitive visual representation of finite automata
Try clicking in the applet area to the right :
You may create links between quadrants and "states" by click-dragging from a quadrant to the state
Self-links between a quadrant and the state it belongs to is allowed (try self-linking all 4 quadrants of a state)
Enhancements:
- This contains the HTML and the applet class files to run stand alone.

Imager::TimelineDiagram is a Perl extension for creating Timeline Diagrams (designed to show system interaction over time).

SYNOPSIS

use Imager::TimelineDiagram;
use Imager::Font;

my $tg = Imager::TimelineDiagram->new(
#maxTime => 10,
#dataLabelSide => left,
labelFont => Imager::Font->new(file => t/ImUgly.ttf),
);

$tg->set_milestones(qw(A B C D E));

my @points = (
# From, To, AtTime
[A,B,1.0],
[B,C,2.0],
[C,D,3.3],
[D,C,4.3],
[C,A,5.0],
);

$tg->add_points(@points);

$tg->write(foo.png);

Graphics::ColorUtils Perl module is an easy-to-use color space conversions and more.

SYNOPSIS

use Graphics::ColorUtils;

( $y, $i, $q ) = rgb2yiq( $r, $g, $b );
( $r, $g, $b ) = yiq2rgb( $y, $i, $q );
$hex_string = yiq2rgb( $y, $i, $q );

( $c, $m, $y ) = rgb2cmy( $r, $g, $b );
( $r, $g, $b ) = cmy2rgb( $c, $m, $y );
$hex_string = cmy2rgb( $c, $m, $y );

( $h, $l, $s ) = rgb2hls( $r, $g, $b );
( $r, $g, $b ) = hls2rgb( $h, $l, $s );
$hex_string = hls2rgb( $h, $l, $s );

( $h, $s, $v ) = rgb2hsv( $r, $g, $b );
( $r, $g, $b ) = hsv2rgb( $h, $s, $v );
$hex_string = hsv2rgb( $h, $s, $v );

# -----

use Graphics::ColorUtils qw( :gradients );

( $r, $g, $b ) = grad2rgb( $name, $f ); # where 0.0 colorAllocate( hsv2rgb( 270, 0.5, 0.3 ) );.)

Features:

Color Space Conversions
Color space conversions, in particular between the "intuitive" color spaces HSV (Hue/Saturation/Value) and HLS (Hue/Lightness/Saturation) to and from RGB (Red/Green/Blue).
Color Lookup
Color lookup by name for three standard sets of colors: WWW/CSS, SVG, and X11.
Color Gradients
Management of color gradients, which can be indexed by a floating point number in the range 0..1. (Mostly intended for false-color data visualization.)