Man pages matching name gnutls_srtp_set_profile_direct in section 3:

gnutls_srtp_set_profile_direct.3.en	debian 10 / gnutls-doc
gnutls_srtp_set_profile_direct.3.en	debian 11 / gnutls-doc
gnutls_srtp_set_profile_direct.3.en	debian 12 / gnutls-doc