Magro

Magro is a minimal image processing library in Ruby. Magro uses Numo::NArray arrays as image objects and provides basic image processing functions. Current supporting features are reading and writing JPEG and PNG images, image resizing with bilinear interpolation method, and image filtering.

Installation

Magro dependents libpng and libjpeg to provides functions reading and writing image file. Moreover, it is recommended that using libpng version 1.6 or later.

macOS:

$ brew install libpng libjpeg

Ubuntu (bionic):

$ sudo apt-get install libpng-dev libjpeg-dev

Add this line to your application's Gemfile:

gem 'magro'

And then execute:

$ bundle

Or install it yourself as:

$ gem install magro

If you use homebrew on Apple M1 mac, specify the homebrew installation directory:

$ gem install magro -- --with-opt-dir=/opt/homebrew

Documentation

• Magro API Documentation

Usage

> require 'magro'
=> true
> image = Magro::IO.imread('foo.png')
=> Numo::UInt8#shape=[512,512,3]
> grayscale = image.median(axis: 2)
=> Numo::UInt8#shape=[512,512]
> Magro::IO.imsave('foo_gray.png', grayscale)
=> true

Contributing

Bug reports and pull requests are welcome on GitHub at github.com/yoshoku/magro. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

The gem is available as open source under the terms of the BSD-3-Clause License.