Abstract: A secret sharing storage system includes at least one user terminal, n units (n: an integer of 2 or more) of storage devices, and a main controller that is communicably connected to a random number generator. The main controller acquires a random number generated by the random number generator in a case of receiving original data sent from the user terminal, executes distributed processing on the original data by using the random number to generate n pieces of distributed data, and stores the n pieces of distributed data respectively in the corresponding n units of storage devices.

Abstract: A resolution converter converts input image data to N types (N is a plural number) of image data having resolutions different with each other. A secret sharing unit performs secret sharing schemes so that the plurality of pieces of image data are respectively divided into n pieces (n is an integer equal to or more than N+1 and the same value in all of image data) of distributed data and the distributed data is reconstructed to original image data using k pieces (k is an integer equal to or more than 2 and equal to or less than n and different value for each piece of image data) among n pieces. A data combination unit generates n pieces of combination data by combining distributed data selected one by one so as not to overlap with each of resolutions and stores each piece of the combination data in different storages.

Abstract: A signature to be used to verify whether or not an original version video captured by a camera has been altered is assigned in the camera to improve the evidential quality of the original version video captured by the camera. The camera (2) includes: an image pickup unit that captures a video of an area to be monitored; a CPU that generates, using a portion or the entirety of video data of the area to be monitored captured by the image pickup unit, a signature for verifying whether or not the video data have been altered; and a network communication unit that sequentially transmits, to a client terminal (4), signed video data obtained by assigning the signature generated by the CPU to the video data.

Abstract: A resolution converter converts input image data to N types (N is a plural number) of image data having resolutions different with each other. A secret sharing unit performs secret sharing schemes so that the plurality of pieces of image data are respectively divided into n pieces (n is an integer equal to or more than N+1 and the same value in all of image data) of distributed data and the distributed data is reconstructed to original image data using k pieces (k is an integer equal to or more than 2 and equal to or less than n and different value for each piece of image data) among n pieces. A data combination unit generates n pieces of combination data by combining distributed data selected one by one so as not to overlap with each of resolutions and stores each piece of the combination data in different storages.

Abstract: An encryption device includes a sharer that shares data to first data and second data with different sizes using secret sharing, a data encryptor that encrypts the second data with the size smaller than the first data using a common key corresponding to a common key encryption scheme, a combiner that combines the first data and the second data encrypted by the data encryptor, and a transmitter that transmits the encrypted data combined by the combiner to an external device. The encryption device suppresses deterioration in security at the time of delivery of the data while reducing a load of an encryption process for the data to be delivered.

Abstract: A first image processing device of an image processing system performs a blurring process on captured first image data, obtains second image data, performs a distribution process on the first image data or third image data based on the first image data, obtains a plurality of shares, and transmits the second image data and the plurality of shares to at least one designated storage device. A second image processing device of the image processing system receives the second image data and the plurality of shares from the at least one designated storage device, and restores the first image data based on at least the plurality of shares.