Patent ID: 7342880
Filing Date: 2008-03-11
Classification: H04N

Abstract:
1. A video information transmission system for transmitting compressed video data, comprising: transmission means, provided on a sender side, for packetizing the compressed video data in units of frames or in small area encoding units, and transmitting the packetized compressed video data; and transmission control means, provided on the sender side, for controlling transmission of the transmission means using congestion information on a network, wherein the congestion information on the network includes at least a network jitter and a packet loss rate, and is categorized into a plurality of congestion levels by a queue overflow detection processing performed on a network gateway based on the packet loss rate, and by a propagation delay increase detection processing by a threshold processing conducted to a variation of the network jitter, whereby a congestion state of the network is determined, wherein a determination result of the congestion state of the network is used to control transmission while avoiding congestion by changing the transmission bit rate according to the determination result, wherein increase of the transmission bit rate is instructed only if the variation of the network jitter is not more than a first threshold and the packet loss rate is not more than a second threshold, and the variation of the network jitter is not more than a third threshold (third threshold<first threshold) or the packet loss rate is not more than a fourth threshold (fourth threshold<second threshold), and wherein if the packet loss rate is more than the first threshold, an extreme congestion is assumed, wherein if the packet loss rate is not more than the first threshold and the variation of the network jitter is more than the second threshold, a middle-level congestion is assumed, and wherein if the packet loss rate is not more than the first threshold and the variation of the network jitter is not more than the second threshold and the packet loss rate is not more than a third threshold (third threshold<first threshold) or the variation of the network jitter is not more than a fourth threshold (fourth threshold<second threshold), a case where the congestion is being eliminated or has been eliminated is assumed, then increase of the transmission bit rate is instructed.