Displaying caller's picture on incoming call

[igor_elx]

Hi,
I have tested on Yealink T58V displaying image from Call-Info header.
It works only with the version of Call-Info header:
Call-Info: <Image URL>;purpose=icon
The phone did not recognize another version: Call-Info: icon="URL".

Example INVITE message with Call-Info header:

Code:

INVITE sip:803@10.25.88.63:5260;transport=UDP SIP/2.0
v: SIP/2.0/UDP 10.25.88.28:5060;branch=z9hG4bK-o-1548917061633031-040560-101
f: <sip:801@10.25.88.28;user=phone>;tag=ecssO1548917061633040040560
t: <sip:803@10.25.88.63;user=phone>
i: BA:7edbdc68d51a6fd8:7edbdc6ce8925c4a
CSeq: 1 INVITE
User-Agent: Eltex ECSS-10 SIP 3.14.0.87
Max-Forwards: 69
m: <sip:801@10.25.88.28:5060;line=89d088c8080cc588>
Accept: multipart/mixed, application/sdp
Allow: INVITE, ACK, BYE, CANCEL, PRACK, REGISTER, INFO, REFER, NOTIFY, OPTIONS, SUBSCRIBE, MESSAGE, UPDATE, PUBLISH
u: presence, dialog, conference
Call-Info: <https://sites.psu.edu/siowfa16/files/2016/10/YeDYzSR-10apkm4-300x295.png>;purpose=icon
Category: 10
x: 1800;refresher=uac
Min-SE: 300
k: 100rel, timer, replaces
P-Eltex-Info: d.local 803@10.25.88.28/- 2437449096 sip1@igorbulanov <0.4056.0>/1 outgoing
c: application/sdp
l: 577

Is it possible on yealink ip-phones to enlarge the image received by incoming call through SIP-header Call-Info?
Are there any other supported mechanisms for receiving image of the caller during an incoming call?

Thanks and best regards, Igor (igor.bulanov@eltex-co.ru)