Install libpng version 1.6 for Ubuntu 19?

How to install libpng for Ubuntu 19 so that I would be able to open Packet Tracer 7.2.1?

2 Answers

If your question is only about how to install libpng16, open a terminal and run:

sudo apt install libpng16-16

This should work for both Ubuntu 19.04 (Disco) and 19.10 (Eoan), since both versions contain the libpng16-16 package in their repositories.

Steps done with Ubuntu 18.04

1. Search libpng packages:

   apt-cache search libpng

   Got this result:

   libpng-dev - PNG library - development (version 1.6)
   libpng-tools - PNG library - tools (version 1.6)
   libpng16-16 - PNG library - runtime (version 1.6)
   fp-units-gfx - Free Pascal - graphics-library units dependency package
   fp-units-gfx-3.0.4 - Free Pascal - graphics-library units
   libpnglite0 - lightweight C library for loading and writing PNG images
   pngquant - Utilitaire d'optimisation d'images PNG (Portable Network Graphics)
   libpng++-dev - C++ interface to the PNG (Portable Network Graphics) library
   libpng-sixlegs-java - Sixlegs Java PNG Decoder
   libpng-sixlegs-java-doc - Documentation for Sixlegs Java PNG Decoder
   libpnglite-dev - lightweight C library for loading and writing PNG images
   ruby-oily-png - native mixin to speed up ChunkyPNG
   tkpng - PNG photo image support to Tcl/Tk

2. Install adequate package:

   sudo apt install libpng16-16

3. Install feature package (optionnal):

   sudo apt install libpng-tools

libpng-tools could be useful, but I don't think it must be install to run Packet Tracer (but probably compulsory for advanced features

NB: -cache option gives you easily package names