So, this sounds like a form of Early Media, but including video as well
as (or instead of?) audio?Yes, it includes audio and video as a way to entertain the caller until the
call has been answered.
In that case, assuming the equipment being used by A is capable of supporting
video, you “merely” need to get the source of the video inserted into the SDP
which Asterisk sends to A. I’ve no idea whether Asterisk’s standard early
media function includes video support, but if you’re prepared to fiddle with
the source code, given that Asterisk supports early media, and also supports
video, I wouldn’t expect it to be too hard to add this feature if it’s not
already there.
How to get video preview? may help if
you didn’t find it already.
For the time being, I am using PortSIP for development. But the project
will later on be integrated with a mobile operator and enable this feature
with a mobile phone’s default dialer. (I understand that it might not work
on all devices and it only works on LTE devices)
You’ve gone way beyond my understanding of what a mobile phone (using standard
calling, and not some extra app such as WhatsApp etc) could achieve.
A user can upload whatever video they prefer to our servers and set it as
their default V-RBT to be played when someone is calling them.
Sounds quite undesirable for the caller, in my opinion. If I make a phone
call, I want to talk to the person I’m calling. I don’t want to get some
video played at me, which is presumably either advertising the services of the
company the callee works for, or showing me what the callee’s cat has done
recently.
Because in production, callers will be initiating the call with their
default dialer and not with a custom mobile application.
I don’t know where in the world you are, and which mobile operator/s you’re
dealing with, but do you really have a service where you can place a standard
call using the native dialler on your mobile phone, and get video?
I’ve never heard of this being possible.
Antony.