Class: SVGProfiler::Histogram

Inherits:
Object
  • Object
show all
Defined in:
lib/svg_profiler/histogram.rb

Constant Summary collapse

WARN_THRESHOLD = 
0.02

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(xml_string, png) ⇒ Histogram

Returns a new instance of Histogram.



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# File 'lib/svg_profiler/histogram.rb', line 9

def initialize(xml_string, png)
  check_for_imagemagick
  @image = Magick::Image.read(png.path).first
  @palette = SVGPalette.parse(xml_string)
end

Class Method Details

.for(xml_string, png) ⇒ Object 



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# File 'lib/svg_profiler/histogram.rb', line 5

def self.for(xml_string, png)
  new(xml_string, png).histogram
end

Instance Method Details

#histogram ⇒ Object 



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# File 'lib/svg_profiler/histogram.rb', line 15

def histogram
  @image.quantize(8) # 00-FF is 8-bits.

  histogram = @image.color_histogram
  frequencies = histogram.inject({}) do |hash, (p, f)|
    hash.merge(to_hex(p) => f)
  end

  filter_by_palette!(frequencies)
  normalize(frequencies)
end