Class: FoggyMirror::Vips

Inherits:
Object
  • Object
show all
Defined in:
lib/foggy-mirror/adapters/vips.rb

Instance Method Summary collapse

Constructor Details

#initialize(path) ⇒ Vips

Returns a new instance of Vips.



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# File 'lib/foggy-mirror/adapters/vips.rb', line 12

def initialize(path)
  @path = path
end

Instance Method Details

#color_samples(res) ⇒ Object 



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# File 'lib/foggy-mirror/adapters/vips.rb', line 20

def color_samples(res)
  square_image(res).to_a.flatten(1)
end

#data_uri(res, format: '.gif', options: {}) ⇒ Object

format and options are passed to Vips’ #write_to_buffer.

We use .gif as the default format as it’s by far the most size-efficient format for very small images. E.g. a 5x5 GIF is around 171 bytes, while an equivalent PNG would be around 2780 bytes, and JPEG would be larger still.

Raises:

  • (ArgumentError) 


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# File 'lib/foggy-mirror/adapters/vips.rb', line 31

def data_uri(res, format: '.gif', options: {})
  image_type = if format.downcase.match?(/\.jpe?g/)
                 'jpeg'
               else
                 format.downcase.match(/\.(png|gif)/)[1]
               end

  raise(ArgumentError, 'Unsupported image format') unless image_type

  base64 = Base64.strict_encode64(square_image(res).write_to_buffer(format, **options)).chomp

  "data:image/#{image_type};base64,#{base64}"
end

#dominant_color ⇒ Object 



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# File 'lib/foggy-mirror/adapters/vips.rb', line 16

def dominant_color
  color_avg(load_image(DEFAULT_RESOLUTION))
end