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This gem is a Ruby binding for thelibvips image processinglibrary. It has been tested onLinux, macOS and Windows, and with ruby 2, ruby 3 and jruby. It usesruby-ffi to call functions in the libvipslibrary.

libvips is ademand-driven, horizontallythreadedimage processing library. Compared to similarlibraries,libvips runs quickly and uses littlememory.libvips is licensed under theLGPL2.1+.

Install the libvips binary with your package manager (eg.apt install libvips42 or perhapsbrew install vips, see thelibvips installinstructions) then installthis gem with:

gem install ruby-vips

Or includegem "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 includegem "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://libvips.github.io/libvips/API/current/libvips-conversion.html#vips-embedim=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 arefull API docs for ruby-vips onrubydoc. This sometimes has issuesupdating, so we have acopy on the gh-pages for this site aswell, whichshould always work.

See theVips section in the docs for atutorial introduction withexamples.

Thelibvips reference manualhas a complete explanation of every method.

Theexample/directory has some simple example programs.

The benchmark atvips-benchmarksloads a large image, crops, shrinks, sharpens and saves again, and repeats10 times.

real time in seconds, fastest of five runsbenchmark       tiff    jpegruby-vips.rb0.850.78image-magick2.032.44rmagick.rb3.873.89peak memory use in kbbenchmarkpeak RESruby-vips.rb43864rmagick.rb788768

See alsobenchmarks at the official libvipswebsite.