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sudo yum install -y ImageMagick

Add package repositoryLibrary for showing multimedia contents.

sudo yum -y install epel-release
sudo rpm -Uvh http://li.nux.ro/download/nux/dextop/el7/x86_64/nux-dextop-release-0-5.el7.nux.noarch.rpm
sudo yum install -y ffmpeg

Library for making PDF cover page.(PDFTK is unavailable for CentOS7, please skip this section. WEKO is looking for alternative method)

Library for showing multimedia contents.

sudo wget https://copr.fedorainfracloud.org/coprs/robert/gcj/repo/epel-7/robert-gcj-epel-7.repo -P /etc/yum.repos.d
sudo wget https://copr.fedorainfracloud.org/coprs/robert/pdftk/repo/epel-7/robert-pdftk-epel-7.repo -P /etc/yum.repos.d
sudo yum install -y ffmpegpdftk

Middleware Setup and Configuration

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In the [Management] => [Server Setting] tab, you can find "Server Environment" menu.
Clicking the [Execute]  button automatically search the commands and change signal color to green if the system has.
In order to store the path to the commands, click the [Commit] button after this operation. 

Library for making PDF cover page.(PDFTK is unavailable for CentOS7, please skip this section. WEKO is looking for alternative method)