To provide a technique capable of alleviating deviation of speakers when a remote conference, etc. is performed using a plurality of communication terminals.

A terminal 10 transmits voice data expressing voice collected by a microphone and video data expressing a video taken by a photography part to the other terminal 10. In addition, the terminal 10 receives the video data and the voice data from the other terminal 10, emits the received voice data from a speaker as sound, outputs the video data on a display to display the video. At this point, a control part detects sound pressure of the voice data expressing the voice collected by the microphone, and analyzes temporal change of the sound pressure to calculate utterance time of a user. The control time calculates ratio of the utterance time by every terminal 10 from calculation results, outputs data indicating the calculation results to the display and thus, notifies the participants of the conference of the calculation results.