Patent ID: 7920178

Claim:
A video storage system comprising: a plurality of video storage devices for recording video data captured by a video capture device, the video data being in the form of a plurality of frames, wherein each of the video storage devices includes a recording unit for recording video data and a check unit for checking whether another video storage device is operating normally, wherein two of the plurality of video storage devices are paired and check each other using their check units and one of the paired video storage devices serves as a master video storage device, and the other of the paired video storage devices serves as a slave video storage device, and the master video storage device includes a video reception unit configured with software for receiving the video data captured by the video capture device; wherein the video reception unit, when a check result obtained by a check unit indicates that the master video storage device is operating normally, distributes the received plurality of frames to the paired video storage devices, the frames being divided, after being received by the video reception unit, into alternative sequences of frames for distribution, one of the alternative sequences including odd-numbered frames, and another of the alternative sequences including even-numbered frames, the distribution being such that the odd-numbered frames are distributed to one of the paired video storage devices, and the even-numbered frames are distributed to the other of the paired video storage device; wherein each of the paired video storage devices operates according to a mode based on the check result obtained by the check unit and the slave video storage device goes into a degraded master mode in which the slave video storage device operates as a master video storage device starting a reception process of software for configuring a video reception unit and recording both of odd-numbered frames and even-numbered frames into the recording unit and using a representative Internet Protocol (IP) address previously used by the master video storage device, if the check result obtained by the check unit indicates that the master video storage device has stopped operating normally.