ZoneMinder 1.33.1 (master nightly) on Ubuntu 19.04 

After upgrading to Ubuntu 19.04 I wanted to try the latest master snapshot of ZoneMinder 1.33.1 from the master ppa. Unfortunately there are older library dependencies for libx264-152 and libmp4v2 that are no longer available in the Ubuntu 19.04, disco repos. I found that I could easily just download the older .deb files and install without issue, which then allowed me to install the latest ZoneMinder 1.33.1 .

For reference:
apt-cache depends zoneminder |grep "libmp4v2|libx264"
Depends: libmp4v2-2
Depends: libx264-155
|Depends: <libx264-142>
|Depends: <libx264-148>
Depends: libx264-152

There is nothing really special other for the other install steps on Ubuntu 19.04 and this guide for Ubuntu 18.04 can be followed for the other steps:

https://wiki.zoneminder.com/Ubuntu_Server_18.04_64-bit_with_Zoneminder_1.32.x_the_easy_way

This is how you can add the master repository with the latest ZoneMinder 1.33.1:

sudo add-apt-repository ppa:iconnor/zoneminder-master
sudo apt update

and this is how you would install the 2 older library dependencies:

https://packages.ubuntu.com/bionic/amd64/libx264-152/download

cd /tmp
wget http://mirrors.kernel.org/ubuntu/pool/universe/x/x264/libx264-152_0.152.2854+gite9a5903-2_amd64.deb
sudo apt install /tmp/libx264-152_0.152.2854+gite9a5903-2_amd64.deb

https://ubuntu.pkgs.org/18.04/ubuntu-universe-amd64/libmp4v2-2_2.0.0~dfsg0-6_amd64.deb.html

cd /tmp
wget http://archive.ubuntu.com/ubuntu/pool/universe/m/mp4v2/libmp4v2-2_2.0.0~dfsg0-6_amd64.deb
sudo apt install /tmp/libmp4v2-2_2.0.0~dfsg0-6_amd64.deb

You should now see that the 2 packages are installed:

apt list --installed |grep "libmp4v2|libx264"
WARNING: apt does not have a stable CLI interface. Use with caution in scripts.
libmp4v2-2/now 2.0.0~dfsg0-6 amd64 [installed,local]
libx264-152/now 2:0.152.2854+gite9a5903-2 amd64 [installed,local]
libx264-155/disco,now 2:0.155.2917+git0a84d98-2 amd64 [installed,automatic]

After following the earlier guide and installing the two dependencies you can just do a:

sudo apt install zoneminder