Class: ImageVise::AutoWriter

Inherits:
Object
  • Object
show all
Defined in:
lib/image_vise/writers/auto_writer.rb

Overview

Picks the most reasonable “default” output format for web resources. In practice, if the image contains transparency (an alpha channel) PNG will be chosen, and if not - JPEG will be chosen. Since ImageVise URLs do not contain a file extension we are free to pick the suitable format at render time

Constant Summary collapse

PNG_EXT = 
'png'
JPG_EXT = 
'jpg'

Instance Method Summary collapse

Instance Method Details

#write_image!(magick_image, _, render_to_path) ⇒ Object 



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# File 'lib/image_vise/writers/auto_writer.rb', line 8

def write_image!(magick_image, _, render_to_path)
  # If processing the image has created an alpha channel, use PNG always.
  # Otherwise, keep the original format for as far as the supported formats list goes.
  extension = magick_image.alpha? ? PNG_EXT : JPG_EXT
  magick_image.format = extension
  magick_image.write(render_to_path)
end