It can be done by via ISAPI after enabling the common gateway interface (CGI) protocol on the camera. Using curl or a HTTP request the ircutFilter can be manually set.
Are you developing an app or would controlling the setting via your browser be sufficient?
Via the camera's webGUI, go to Configuration>Network>Advanced Settings>Integration Protocol.
Enable CGI and set authentication to digest/basic. For ISAPI, enable ONVIF and create a user with the same credentials as the admin login.
Could you help me with the ircutfilter command, please. A http request would be easiest for me but I can‘t find the command in the ISAPI reference guide.