Patent ID: 7791748

Claim:
An image communication control method for conducting image communication by using one of a plurality of different image communication systems via sending/receiving paths including an IP network, wherein a transmitter and receivers for conducting the image communication or devices for relaying the image communication existing in the sending/receiving paths include SDP media stream descriptions in an SIP message and send it on the basis of an SIP protocol, the SDP media stream descriptions comprising different image communication systems usable by the transmitter and the receivers for conducting the image communication and image communication control parameters described based on given syntaxes; wherein the transmitter and the receivers for conducting the image communication select an image communication system for use in practical image communication and image communication control parameters to be used in the appropriate image communication system in given order of priority on the basis of the SDP media stream descriptions in the SIP message received from an apparatus in the opponent party and control the image communication and output processing in the image receiving party by using the selected image communication system and image communication control parameters, wherein when the image communication control parameters of the SDP media stream descriptions are parameters indicating that image data is sent or received in the considered-speech ITU-T Recommendation T.30 facsimile communication system, they include information specifying a speech encoding method suitable for digital/analog conversion of a speech signal, and wherein the image communication system for use in the image communication and the image communication control parameters to be used in the appropriate image communication system are selected in order of priority based on order of appearance in the SDP media stream descriptions in the SIP message.