Interlaced Image with RMagick

Question

ImageMagick has an interlace option, which RMagick supports, but I can't work out the syntax for this. I can see Magick::InterlaceType and Magick::LineInterlace are both valid constants, but how to save an image using those constants?

Answer 1

require 'rubygems'
require 'RMagick'

img = Magick::Image.new(300, 50) do
  self.background_color = '#FFFF00'
end
img.write('test.jpg') { self.interlace = Magick::PlaneInterlace }

#check the interlace property
puts img.interlace # PlaneInterlace