There are provided a multi-point conference system and a multi-point
conference device capable of using an SIP terminal as a conference
terminal and clearly and smoothly performing speaker switching without
requesting a conference terminal to transmit an intra frame when a
speaker is detected. The multi-point connection device includes an image
processing unit for accumulating in a memory (13), image data from the
conference terminal participating in the conference, and decoding the
image data on the speaker accumulated in the memory (13) and re-encoding
the decoded image upon detection of a speaker in a medium processing unit
(15). Upon switching of a speaker, the image processing unit re-encodes
the first image as an intra frame and transmits the image data to
conference terminals other than that of the speaker, so that the
conference terminals other than that of the speaker can perform decoding
from the intra frame, thereby clearly and smoothly performing the speaker
switching.