I needed a newer version of ImageMagick than is available on the yum packages on Amazon Linux. I tried using the remi repo but it failed with dependency errors. Here is what I did to install ImageMagick with support for PNG, JPG, and TIFF.
download the most recent package
wget http://www.imagemagick.org/download/ImageMagick.tar.gz
uncomress the package
tar -vxf ImageMagick.tar.gz
installl the developer tools for linux
sudo yum groupinstall "Development tools"
install the devel packages for png, jpg, tiff. these are dependencies of ImageMagick
sudo yum -y install libpng-devel libjpeg-devel libtiff-devel
configure ImageMagick without X11. this is a server without a display (headless) so we don't need X11
cd ImageMagick
./configure --without-x
make && make install
Validate Install
make check
Install ExifTool
wget http://www.sno.phy.queensu.ca/~phil/exiftool/Image-ExifTool-10.05.tar.gz
Extract ExifTool
tar -vxf Image-ExifTool-10.05
Install dependencies
sudo yum install perl-devel perl-CPAN
Make and install ExifTool
perl Makefile.PL
make test
sudo make install
mission complete.