Installing RMagick Gem

use rvm to install ruby (preferred) or use apt-get install ruby ruby-dev

aptitude install build-essential imagemagick libmagickcore-dev libmagickwand-devgem install rmagick

--Edit 1--

sudo apt-get install ruby-dev

You will also need ruby-dev (or ruby-full) for successfully compiling the RMagick before gem install.

ruby linux ubuntu rmagick

sudo apt-get install imagemagick libmagickwand-dev

gem install rmagick

in gem file

gem 'rmagick'

then run

bundle install

CodeHunter