This gem is a Ruby binding for the libvips image processing library. It has been tested on Linux, macOS and Windows, and with ruby 2, ruby 3 and jruby. It uses ruby-ffi to call functions in the libvips library.

libvips is a demand-driven, horizontally threaded image processing library. Compared to similar libraries, libvips runs quickly and uses little memory. libvips is licensed under the LGPL 2.1+.

Install the libvips binary with your package manager (eg. apt install libvips42 or perhaps brew install vips, see the libvips install instructions) then install this gem with:

gem install ruby-vips 

Or include gem "ruby-vips" in your gemfile.

The gemspec will pull in the msys libvips for you, so all you need is:

gem install ruby-vips 

Or include gem "ruby-vips" in your gemfile.

Tested with the ruby and msys from choco, but others may work.

require"vips"im=Vips::Image.new_from_filefilename# put im at position (100, 100) in a 3000 x 3000 pixel image, # make the other pixels in the image by mirroring im up / down / # left / right, see# https://www.libvips.org/API/current/method.Image.embed.htmlim=im.embed100,100,3000,3000,extend: :mirror# multiply the green (middle) band by 2, leave the other two aloneim *= [1,2,1]# make an image from an array constant, convolve with itmask=Vips::Image.new_from_array[[-1, -1, -1],[-1,16, -1],[-1, -1, -1]],8im=im.convmask,precision: :integer# finally, write the result back to a file on diskim.write_to_fileoutput_filename

There are full API docs for ruby-vips on rubydoc. This sometimes has issues updating, so we have a copy on the gh-pages for this site as well, which should always work.

See the Vips section in the docs for a tutorial introduction with examples.

The libvips reference manual has a complete explanation of every method.

The example/ directory has some simple example programs.

The benchmark at vips-benchmarks loads a large image, crops, shrinks, sharpens and saves again, and repeats 10 times.

real time in seconds, fastest of five runs benchmark tiff jpeg ruby-vips.rb 0.85 0.78 image-magick 2.03 2.44 rmagick.rb 3.87 3.89 peak memory use in kb benchmark peak RES ruby-vips.rb 43864 rmagick.rb 788768 

See also benchmarks at the official libvips website.