Error installing libjasper-dev and libpng12 package in ubuntu 19.04

I tried to install libjasper-dev and libpng12 for opencv but I'm getting this error:

E: Unable to locate package libjasper-dev E: Unable to locate package libpng12

I also tried installing libpng16 but still I was getting the same error. How can I solve this problem?

3 Answers

Alternative solution:

1. Add the following to etc/apt/source.list - this is a document you can navigate to in file manager

### Preface with a comment is optional
### Helps to remember why something was added to the list later on
### Added for libjasper-dev
deb xenial-security main 

2. Update the package index

sudo apt-get update

3. Install libjasper-dev

sudo apt-get install libjasper-dev

P.S. You may want to keep in mind that this library may be outdated or not intended for your version of Linux, so there's always a possibility that what you want it for will not work properly or stop working eventually.

To install libjasper-dev using below:

Add the following line to /etc/apt/sources.list:
deb bionic main
Install GPG key of the repository:
# sudo apt-key adv --keyserver keyserver.quickbuild.io --recv-keys F5CFC95C
Update the package index:
# sudo apt-get update
Install libjasper-dev deb package:
# sudo apt-get install libjasper-dev

Reference

To install libpng12 refer below link

E: Package 'libpng12-0' has no installation candidate [ubuntu 16.10 Gnome]

You can install it:

apt-get install libpng-dev

You can download the source code from here and build:

$ wget
$ wget 

And export the library path as follow:

$ export JASPERLIB=/home/user/build/grib2/lib
$ export JASPERINC=/home/user/build/grib2/include