Class: Abachrome::Converters::SrgbToCmyk

Inherits:
Object
  • Object
show all
Defined in:
lib/abachrome/converters/srgb_to_cmyk.rb

Class Method Summary collapse

Class Method Details

.convert(srgb_color, gcr_amount: 1.0) ⇒ Abachrome::Color

Converts a color from sRGB color space to CMYK color space. Uses full GCR (Gray Component Replacement) by default for optimal ink usage.

with the same alpha value as the input color

Parameters:

  • srgb_color (Abachrome::Color) —

    A color object in the sRGB color space

  • gcr_amount (Numeric) (defaults to: 1.0) —

    The amount of GCR to apply (0.0 to 1.0), default 1.0 for full GCR

Returns:



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# File 'lib/abachrome/converters/srgb_to_cmyk.rb', line 31

def self.convert(srgb_color, gcr_amount: 1.0)
  r, g, b = srgb_color.coordinates.map { |c| AbcDecimal(c) }

  # Use GCR conversion from the CMYK color model
  c, m, y, k = ColorModels::CMYK.from_rgb_gcr(r, g, b, gcr_amount)

  Color.new(
    ColorSpace.find(:cmyk),
    [c, m, y, k],
    srgb_color.alpha
  )
end

.convert_naive(srgb_color) ⇒ Abachrome::Color

Converts a color from sRGB to CMYK using the naive method (no UCR/GCR). This produces higher ink coverage but simpler conversion. Generally not recommended for production printing.

Parameters:

Returns:



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# File 'lib/abachrome/converters/srgb_to_cmyk.rb', line 50

def self.convert_naive(srgb_color)
  r, g, b = srgb_color.coordinates.map { |c| AbcDecimal(c) }

  # Use naive conversion from the CMYK color model
  c, m, y, k = ColorModels::CMYK.from_rgb_naive(r, g, b)

  Color.new(
    ColorSpace.find(:cmyk),
    [c, m, y, k],
    srgb_color.alpha
  )
end