sudo apt-get install libmagickwand-dev imagemagick

sudo apt-get install libmagickwand-dev imagemagick

Building native extensions.  This could take a while...
ERROR:  Error installing rmagick:
ERROR: Failed to build gem native extension.
   /home/ubuntu/.rvm/rubies/ruby-2.2.1/bin/ruby -r ./siteconf20151106-26672-3q6a8w.rb extconf.rb
checking for gcc... yes
checking for Magick-config... no
checking for pkg-config... yes
Package MagickCore was not found in the pkg-config search path.
Perhaps you should add the directory containing `MagickCore.pc'
to the PKG_CONFIG_PATH environment variable
No package 'MagickCore' found
checking for outdated ImageMagick version (<= 6.4.9)... *** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary
libraries and/or headers.  Check the mkmf.log file for more details.  You may
need configuration options.
Provided configuration options:
--with-opt-dir
--without-opt-dir
--with-opt-include
--without-opt-include=${opt-dir}/include
--with-opt-lib
--without-opt-lib=${opt-dir}/lib
--with-make-prog
--without-make-prog
--srcdir=.
--curdir
--ruby=/home/ubuntu/.rvm/rubies/ruby-2.2.1/bin/$(RUBY_BASE_NAME)
extconf failed, exit code 1
Gem files will remain installed in/home/ubuntu/.rvm/gems/ruby-2.2.1/gems/rmagick-2.15.4 for inspection.
Results logged to/home/ubuntu/.rvm/gems/ruby-2.2.1/extensions/x86_64-linux/2.2.0/rmagick-2.15.4/gem_make.out