gegl software package provides Generic Graphics Library Test Program, 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 gegl
gegl is installed in your system.
Make ensure the gegl package were installed using the commands given below,
$ sudo dpkg-query -l | grep gegl *
You will get with gegl package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Libraries |
| Package | gegl |
| Version | 0.3.8-3 |
| Description | Generic Graphics Library Test Program |
| Sub Section | Libs |