Start by removing any old versions previously installed via apt-get:
sudo apt-get remove imagemagick
Then update apt-get and install some supporting packages:
sudo apt-get update
*(sudo apt-get install
libperl-dev gcc libjpeg62-dev libbz2-dev
libtiff4-dev libwmf-dev libz-dev libpng12-dev
libx11-dev libxt-dev libxext-dev libxml2-dev
libfreetype6-dev liblcms1-dev libexif-dev perl
libjasper-dev libltdl3-dev graphviz gs-gpl pkg-config)*
*its a single line command.
get the Imagemagick package from this link:
http://www.imagemagick.org/script/install-source.php#unix
Once the source is downloaded, uncompress it:
tar -xzf ImageMagick.tar.gz
Now configure and make:
cd ImageMagick-6.5.0-0
./configure
sudo make
sudo make install
Add the following line to ~/.bashrc:
export LD_LIBRARY_PATH=/usr/local/lib
Update: If you still get an error like the one above, try running ldconfig:
sudo ldconfig
You can confirm the install and available formats with:
identify -list format
Once Image magick is installed install rmagick gem by typing the command:
$sudo gem install rmagick
