class RPDiff

Attributes

fov[R]

gamma[R]

identical[R]

img1[R]

img2[R]

incomparable[R]

indistinguishable[R]

luminance[R]

match_percentage[R]

pixel_difference[R]

threshold[R]

visibly_different[R]

Public Class Methods

new(img1, img2, options={}) click to toggle source

# File lib/rpdiff.rb, line 9
def initialize(img1, img2, options={})
  @img1, @img2, @options = img1, img2, options
end

Public Instance Methods

calculate_match_percentage() click to toggle source

Optional gem requirement to get a % value out of image similarity.

# File lib/rpdiff.rb, line 36
def calculate_match_percentage
  return 0 if incomparable
  @image_sizes = FastImage.size(@img1)
  @match_percentage = 100 - (@pixel_difference.to_f * 100 / (@image_sizes.first * @image_sizes.last).to_f)
end

diff() click to toggle source

# File lib/rpdiff.rb, line 13
def diff
  @indistinguishable = @visibly_different = @identical = false
  @pixel_difference = 0

  opts = "#{@img1} #{@img2} "
  @options.each {|k, v| opts << "-#{k} #{v} "}
  io = `perceptualdiff #{opts}`

  io.split(/\n/).each do |line|
    @fov               = $1   if line =~ /Field of view is (\d+\.\d+) degrees/
    @threshold         = $1   if line =~ /Threshold pixels is (\d+) pixels/
    @gamma             = $1   if line =~ /The Gamma is (\d+\.\d+)/
    @luminance         = $1   if line =~ /The Display's luminance is (\d+\.\d+) candela per meter squared/
    @pixel_difference  = $1   if line =~ /(\d+) pixels are different/
    @visibly_different = true if line =~ /FAIL: Images are visibly different/
    @identical         = true if line =~ /PASS: Images are binary identical/
    @indistinguishable = true if line =~ /PASS: Images are perceptually indistinguishable/
    @incomparable      = true if line =~ /FAIL: Image dimensions do not match/
  end
  io
end