pngcrush is a free and open-source command-line utility for
optimizing PNG image files. It reduces the size of the file losslessly;
that is, the resulting "crushed" image will have the same quality as the
source image.
Snaps are applications packaged with all their dependencies to run on all popular Linux distributions from a single build. They update automatically and roll back gracefully.
Snaps are discoverable and installable from the Snap Store, an app store with an audience of millions.
For versions of Ubuntu between 14.04 LTS (Trusty Tahr) and 15.10 (Wily Werewolf), as well as Ubuntu flavours that don’t include snap by default, snap can be installed from the Ubuntu Software Centre by searching for snapd.
Alternatively, snapd can be installed from the command line:
sudo apt update
sudo apt install snapd
Either log out and back in again, or restart your system, to ensure snap’s paths are updated correctly.
Install pngcrush
To install pngcrush, simply use the following command: