Class: Riiif::Region::Imagemagick::PercentageDecoder

Inherits:
Object
  • Object
show all
Defined in:
app/services/riiif/region/imagemagick/percentage_decoder.rb

Overview

decodes requested cooridnates into an imagemagick crop directive

Instance Method Summary collapse

Constructor Details

#initialize(image_info, x, y, width, height) ⇒ PercentageDecoder

Returns a new instance of PercentageDecoder.



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# File 'app/services/riiif/region/imagemagick/percentage_decoder.rb', line 6

def initialize(image_info, x, y, width, height)
  @image_info = image_info
  @x = x
  @y = y
  @width = width
  @height = height
end

Instance Method Details

#decode ⇒ String

Imagemagick can’t do percentage offsets, so we have to calculate it

Returns:

  • (String) —

    a region for imagemagick to decode (appropriate for passing to the -crop parameter)



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# File 'app/services/riiif/region/imagemagick/percentage_decoder.rb', line 17

def decode
  "#{@width}%x#{@height}+#{offset_x}+#{offset_y}"
end