pngquant is a free and open source command-line based lossy PNG compressor for Linux, MacOS and windows. It converts png images to a 8-bit PNG format with alpha channel file to reduce the size. It comes with quality palette generation, gamma correction and premultiplied alpha support. During the conversion process it reduces the noise. You can configure the image quality level and it is based on libimagequant. It is released under GNU GENERAL PUBLIC LICENSE. It also supports batch conversion of PNG image files.
Install pngquant PNG compressor on Ubuntu
you can install pngquant PNG compressor via snap on Ubuntu. open your terminal app (ctrl+Alt+T) and type this pngquant snap installation command and press the enter key from your keyboard.
sudo snap install pngquant
Then enter your ubuntu user password if needed. it will install pngquant PNG compressor on Ubuntu.
You can use the below command to compress the png.
example: If you want to compress deluge.png file from the Pictures folder in ubuntu, then run below commands one by one.
The output filename in this example is the same as the input name except that it ends in “-fs8.png”, “-or8.png
Here the output file name “deluge-fs8.png”
To check the complete list of option run this below command on terminal.