No video. How to get the right codec?

After getting my voicemail done i want to enable video.
I have videosupport=yes set in sip.conf

But i have read that for video to work you should support a single video codec.
I have tryed several codec but my softphone application on android does not connect.

I try to figure out the supported codec of the app (skysip, I tryed a lot of apps and this one works with out being powerhungry)

is there a asterisk cli command to get the supported codec of a connected client?

website of the makers is down. Perhaps i need to look for a other android app.

Capture the INVITE with sip set debug on to see what codec they are offerning.

(However, unless there are strong reasons to the contrary, you should be using chan_pjsip.)

I’m a beginner. Will my grandstream hardware work with chan_pjsip?

Is this what the softphone is offering?

o=- 108297813306 1 IN IP4
s=Cpc session
c=IN IP4
t=0 0
m=audio 51330 RTP/AVP 120 9 0 8 18 101
a=rtpmap:120 opus/48000/2
a=fmtp:120 useinbandfec=1; usedtx=1; maxaveragebitrate=64000
a=rtpmap:18 G729/8000
a=fmtp:18 annexb=no
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-15
m=video 65256 RTP/AVP 125 126 120
a=rtpmap:125 H264/90000
a=fmtp:125 profile-level-id=42801f;packetization-mode=0
a=rtpmap:126 H264/90000
a=fmtp:126 profile-level-id=42801f;packetization-mode=1
a=rtpmap:120 VP8/90000
a=rtcp-fb:* nack
a=rtcp-fb:* nack pli

it works. I was testing it with only allowing a video codec. a voice codec is also required.

It is generally only some SIP providers that use SIP in strange ways that have problems.