Patent ID: 8655139

Claim:
A data reading device comprising: a processor operable: for reading, over a communication network, video data recorded in a video processing device which records and plays back video data; and for controlling the reading video data recorded in the video processing device so as to read video data from the video processing device over the communication network (i) by transmitting, over the communication network, a reading request of index data to a video writing device, which writes the video data to the video processing device over the communication network, when a result of a determination from video data read over the communication network from the video processing device is index data of the video data read indicating an address of the video data read is not recorded in the video processing device, and (ii) by transmitting a reading request of video data over the communication network to the video processing device designating the address indicated by the index data transmitted over the communication network from the video writing device responsive to the reading request of index data received at the video writing device, before the index data is written according to a recording update timing by the video writing device to the video processing device over the communication network, wherein the transmitting of the reading request of index data to the video writing device and the transmitting of the reading request of video data to the video processing device designating the address are controlled such that a frame of video data as a reading target can be immediately read from the video processing device by a video reading device over the communication network during recording of the frame and a next frame of the video data to the video processing device by the video writing device independent of a request by the video reading device.