Blurhash

This is a pure ruby implementation of the blurhash algorithm.

There are other Ruby based libraries for this. But all of them use compiled dependencies which tend to cause issues over time.

Currently it only handles encoding.

Install the gem and add to the application's Gemfile by executing:

bash bundle add blurhash-rb

If bundler is not being used to manage dependencies, install the gem by executing:

bash gem install blurhash-rb

If you add it to your Gemfile and want it to be automatically required you need to specify you want to require: "blurhash"

gem "blurhash-rb", require: "blurhash"

To use it you just need to feed in the pixels, width and height of the image.

require "blurhash"

def load_image_as_rgba(path)
  image = ChunkyPNG::Image.from_file(path)
  width = image.width
  height = image.height
  pixels = []

  height.times do |y|
    width.times do |x|
      pixel = image[x, y]
      r = ChunkyPNG::Color.r(pixel)
      g = ChunkyPNG::Color.g(pixel)
      b = ChunkyPNG::Color.b(pixel)
      pixels.push(r, g, b)
    end
  end

  [pixels, width, height]
end

pixels, width, height = load_image_as_rgba("spec/fixtures/test.png")

hash = described_class.call(
  pixels:,
  width:,
  height:,
  component_x: 4,
  component_y: 3
)

puts hash #=> "LEHV6nae2yk8pyo0adR*.7kCMdnj"

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and the created tag, and push the .gem file to rubygems.org.

Bug reports and pull requests are welcome on GitHub at https://github.com/nolantait/blurhash-rb.

The gem is available as open source under the terms of the MIT License.