JP2984927B

PROBLEM TO BE SOLVED: To transfer a dynamic image without delay, even when the load of a network is increased. SOLUTION: Three-dimensional dynamic image data are sent out of a server 1, while combining reference frame data composed of the entire object data of a still picture and the differential value of object data between two still images. At gateways 3 and 4 provided in the middle of a network 2, the band of an output side network is measured at all times. The gateways 3 and 4 find an estimate transfer cycle required for transferring the differential frame data from the length of received differential frame data and network bands. When the estimated transfer cycle is longer than a reference transfer cycle, the gateways 3 and 4 transfer the differential frame data to the side of a client with rough accuracy.