さくらのレンタルサーバに ImageMagick をインストールする方法 ref: http://qiita.com/satosystems/items/b14f8a5b6b23b1f25acb

file0.txt

$ mkdir ~/works
$ cd ~/works
$ wget -c http://www.imagemagick.org/download/ImageMagick.tar.gz
$ tar xf ImageMagick.tar.gz
$ cd ImageMagick-6.9.3-4/
$ ./configure --prefix=$HOME/usr --disable-openmp --disable-opencl
$ make
$ make install
$ echo "export PATH=\$HOME/usr/bin:\$PATH" >> ~/.bash_profile
$ echo "export PKG_CONFIG_PATH=\$HOME/usr/lib/pkgconfig" >> ~/.bash_profile
$ source ~/.bash_profile

file1.txt

$ which convert
/home/xxx/usr/bin/convert

file2.txt

$ convert -version
Version: ImageMagick 6.9.3-4 Q16 x86_64 2016-02-17 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2016 ImageMagick Studio LLC
License: http://www.imagemagick.org/script/license.php
Features: Cipher DPC 
Delegates (built-in): bzlib fftw fontconfig freetype fpx jbig jng jpeg lcms lqr png tiff xml

file3.txt

$ pkg-config --libs ImageMagick
-L/home/xxx/usr/lib -lMagickCore-6.Q16