Gfilui

Im trying to install zoneminder on ubuntu 16.04 server and I get this unmet dependencies error. How can I correct this?

root@tpadzm:/home/joey# apt-get install zoneminder
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
zoneminder : Depends: libavcodec57 (>= 7:3.4.2) but it is not installable or
 libavcodec-extra57 (>= 7:3.4.2) but it is not installable
 Depends: libavformat57 (>= 7:3.4.2) but it is not installable
 Depends: libavresample3 (>= 7:3.4.2) but it is not installable
 Depends: libavutil55 (>= 7:3.4.2) but it is not installable
 Depends: libmp4v2-2 but it is not installable
 Depends: libswscale4 (>= 7:3.4.2) but it is not installable
 Depends: libvlc5 (>= 1.1.1) but it is not installable
 Depends: libx264-152 but it is not installable
 Depends: libjs-mootools (>= 1.4.5~debian1) but it is not 
 installable
 Depends: ffmpeg but it is not installable or
 libav-tools but it is not installable
 Depends: libdbd-mysql-perl but it is not installable
 Depends: libphp-serialization-perl but it is not installable
 Depends: libnet-sftp-foreign-perl but it is not installable
 Depends: libdevice-serialport-perl but it is not installable
 Depends: libimage-info-perl but it is not installable
 Depends: libjson-any-perl but it is not installable
 Depends: libsys-mmap-perl but it is not installable
 Depends: liburi-encode-perl but it is not installable
 Depends: libclass-std-fast-perl but it is not installable
 Depends: libsoap-wsdl-perl but it is not installable
 Depends: libio-socket-multicast-perl but it is not installable
 Depends: libsys-cpu-perl but it is not installable
 Depends: libsys-meminfo-perl but it is not installable
 Depends: libdata-uuid-perl but it is not installable
 Depends: libnumber-bytes-human-perl but it is not installable
 Depends: libfile-slurp-perl but it is not installable
 Depends: php5-apcu but it is not installable or
 php-apcu but it is not installable
 Depends: php-apc but it is not installable or
 php-apcu-bc but it is not installable
 Recommends: zoneminder-doc (>= 1.31.45~20180731103016-bionic) but 
it is not going to be installed
 Recommends: ffmpeg but it is not installable
E: Unable to correct problems, you have held broken packages.
root@tpadzm:/home/joey# apt install libavcodec57
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package libavcodec57 is not available, but is referred to by another 
package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package 'libavcodec57' has no installation candidate
root@tpadzm:/home/joey# cat /etc/apt/sources.list
deb http://archive.ubuntu.com/ubuntu bionic main
deb http://archive.ubuntu.com/ubuntu bionic-security main
deb http://archive.ubuntu.com/ubuntu bionic-updates main
root@tpadzm:/home/joey#

OK, first of all you have wrong sources.list that includes only main channel. So, do sudo gedit /etc/apt/sources.list and make it look like this:

deb http://archive.ubuntu.com/ubuntu bionic main multiverse restricted universe
deb http://archive.ubuntu.com/ubuntu bionic-security main multiverse restricted universe
deb http://archive.ubuntu.com/ubuntu bionic-updates main multiverse restricted universe

Save and exit.
Then update your repository:

sudo apt update