imageruby

flexible and easy to use ruby gem for image processing

tario

Ruby

= ImageRuby - flexible ruby gem for image processing

ImageRuby is a gem for image processing written in pure ruby, this makes the library very portable and easy to install

Also, the gem was desgined to accept extensions like:

new format decoders made from scratch (Ruby or C)
new format decoders based on existent C libraries like libpng, libbmp, etc…
new image operations (Ruby or C)
re-implementations of parts in C to improve performance on environments where it is possible

== Installation

=== Gem installation

sudo gem install imageruby

== Documentation

Full API documentation can be found on:
http://tario.github.com/imageruby/doc/

== Examples

NOTE: Examples loads and saves bitmap files, imageruby-bmp gem must be installed in order
to get the examples work

=== Create and save a black image

require “rubygems”
require “imageruby”

include ImageRuby

creates an image of 150x150 pixels filled with black

image = ImageRuby::Image.new(150,150, Color.black)

begin

this only work if imageruby-bmp gem is installed

image.save(“black.bmp”, :bmp)
rescue
print “Error while trying to save, you must install imageruby-bmp gem”
end

=== Create an image with vertical stripes filled with default named colors

require “rubygems”
require “imageruby”

include ImageRuby

print “list of named colors:\n”
print “--------------------------\n”

colors = Array.new

Color.named_colors.each do |name, color|
print “#{name}: #{color.inspect}\n”
colors << color
end

image = Image.new( colors.count * 32, 512)

x = 0
colors.each do |color|
image[x…x+31, 0…511] = Image.new(32,512,color)
x = x + 32
end

image.save(“colors.bmp”, :bmp)

=== Gradient using block parameter

require “rubygems”
require “imageruby”

include ImageRuby

gradient_images = Array.new

gradient_images << Image.new(64,64) {|x,y|
Color.from_rgb(x4,y4,0)
}

gradient_images << Image.new(64,64) {|x,y|
Color.from_rgb(0,x4,y4)
}

gradient_images << Image.new(64,64) {|x,y|
Color.from_rgb(y4,0,x4)
}

(0…gradient_images.count-1).each do |i|
gradient_images[i].save(“gradient#{i}.bmp”, :bmp)
end

all_gradient = Image.new(96*gradient_images.count, 96)

(0…gradient_images.count-1).each do |i|
all_gradient.draw!(i*96+16, 16, gradient_images[i])
end

all_gradient.save(“gradients.bmp”, :bmp)

=== Draw with mask

require “rubygems”
require “imageruby”

include ImageRuby

colors = Image.from_file(“colors.bmp”)
gradients = Image.from_file(“gradients.bmp”)

without_mask = colors.draw(128,192,gradients)
without_mask.save(“without_mask.bmp”, :bmp)

with_mask = colors.draw(128,192,gradients.mask(Color.black))
with_mask.save(“with_mask.bmp”, :bmp)

=== Draw with transparency effects

require “rubygems”
require “imageruby”

include ImageRuby

colors = Image.from_file(“colors.bmp”)
gradients = Image.from_file(“gradients.bmp”)

transparent_black = Color.black
transparent_black.a = 128

colors.draw(128,192,gradients.color_replace(Color.black, transparent_black)).save(“sample1.bmp”, :bmp)

half_transparent = gradients.map_pixel{ |x,y,c|
c.a = 128 if x >144
c
}
colors.draw(128,192,half_transparent).save(“sample2.bmp”, :bmp)

== Copying