Install libopal-dev by entering the following commands in the terminal:
sudo apt update sudo apt install libopal-dev
Description:
OPAL library header files
This package contains the headers and a static version of the OPAL library. . The OPAL project aims to create a full featured, interoperable, Open Source implementation of the H.323 and SIP protocols that can be used freely by everybody. These protocols are most used for Voice over IP (VoIP) conferencing.
Homepage: http://www.opalvoip.org/
Version: 3.10.10~dfsg2-2.1build2
Section: universe/libdevel