Class: Riiif::Crop

Inherits:
Object
  • Object
show all
Defined in:
app/services/riiif/crop.rb

Overview

Represents a cropping operation

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(region, image_info) ⇒ Crop

Returns a new instance of Crop.

Parameters:

  • transformation (IIIF::Image::Region) —

    the result the user requested

  • image_info — 


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# File 'app/services/riiif/crop.rb', line 6

def initialize(region, image_info)
  @region = region
  @image_info = image_info
end

Instance Attribute Details

#image_info ⇒ Object (readonly)

Returns the value of attribute image_info.



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# File 'app/services/riiif/crop.rb', line 11

def image_info
  @image_info
end

#region ⇒ Object (readonly)

Returns the value of attribute region.



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# File 'app/services/riiif/crop.rb', line 11

def region
  @region
end

Instance Method Details

#to_imagemagick ⇒ String

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

Returns:

  • (String) —

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



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# File 'app/services/riiif/crop.rb', line 15

def to_imagemagick
  case region
  when IIIF::Image::Region::Full
    nil
  when IIIF::Image::Region::Absolute
    "#{region.width}x#{region.height}+#{region.offset_x}+#{region.offset_y}"
  when IIIF::Image::Region::Square
    imagemagick_square
  when IIIF::Image::Region::Percent
    imagemagick_percent
  else
    raise "Unknown region #{region.class}"
  end
end

#to_kakadu ⇒ String

Returns a region for kakadu to decode (appropriate for passing to the -region parameter).

Returns:

  • (String) —

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



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# File 'app/services/riiif/crop.rb', line 32

def to_kakadu
  case region
  when IIIF::Image::Region::Full
    nil
  when IIIF::Image::Region::Absolute
    "\{#{decimal_offset_y(region.offset_y)},#{decimal_offset_x(region.offset_x)}\}," \
    "\{#{decimal_height(region.height)},#{decimal_width(region.width)}\}"
  when IIIF::Image::Region::Square
    kakadu_square
  when IIIF::Image::Region::Percent
    kakadu_percent
  else
    raise "Unknown region #{region.class}"
  end
end