How to install RMagick on Redhat & Ubuntu

For Redhat / Ubuntu( < 10.04)

1. sudo yum install libjpeg-devel libpng-devel glib2-devel fontconfig-devel zlib-devel libwmf-devel freetype-devel libtiff-devel
2. wget ftp://ftp.imagemagick.org/pub/ImageMagick/ImageMagick.tar.gz
3. tar xvfz ImageMagick.tar.gz
4. cd ImageMagick-6.x.x.x
5. ./configure
6. sudo make
7. sudo make install
8. sudo gem install rmagick

For Ubuntu(Lucid)

1. sudo apt-get install imagemagick
2. sudo apt-get install libmagickcore-dev
3. sudo apt-get install libmagickwand-dev 
4. sudo gem install rmagick 

You can verify the installation using this irb command:

   $ sudo irb -rubygems -r RMagick

   irb(main):001:0> puts Magick::Long_version