Grayscale image: Difference between revisions

=={{header|Crystal}}==

{{trans||Ruby}}

Extending [[Basic_bitmap_storage#Crystal]]

<lang ruby>class RGBColour

def to_grayscale

luminosity = (0.2126*@red + 0.7152*@green + 0.0722*@blue).to_i

self.class.new(luminosity, luminosity, luminosity)

end

end

class Pixmap

def to_grayscale

gray = self.class.new(@width, @height)

@width.times do |x|

@height.times do |y|

gray[x,y] = self[x,y].to_grayscale

end

end

gray

end

end</lang>