imagemagick software package provides image manipulation programs -- binaries, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install imagemagick
imagemagick is installed in your system.
Make ensure the imagemagick package were installed using the commands given below,
$ sudo dpkg-query -l | grep imagemagick *
You will get with imagemagick package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Graphics |
| Package | imagemagick |
| Version | 8:6.9.6.2+dfsg-2 |
| Description | image manipulation programs -- binaries |
| Sub Section | Graphics |