Install nomacs by entering the following commands in the terminal:
sudo apt update sudo apt install nomacs
Description:
image viewer with capability of syncing multiple instances
nomacs is a free image viewer for Windows and Linux systems, which is licensed under the GNU General Public License v3. nomacs is small, fast and able to handle the most common image formats. Additionally it is possible to synchronize multiple viewers. A synchronization of viewers running on the same computer or via LAN is possible. It allows one to compare images and spot the differences (e.g. schemes of architects to show the progress).
Homepage: http://www.nomacs.org
Version: 3.8.0+dfsg-4
Section: universe/graphics