Sumitomo Electric Industries, Limited

Tokyo Metropolitan University

Kiyoshi Nishikawa

Toshiaki Kakii

Hitoshi Kiya

Yoichi Hata

Yoshimitsu Goto

Masaaki Fujiyoshi

Yasuhito Fujita

Shoko Imaizumi

A master key (K) inputted by an input unit is stored in a storage unit. A matrix generating unit generates key element matrices (M-M) with respect to each of split keys (e, e, e) obtained by a key dividing unit dividing the master key (K). To each coordinate entry of the key element matrices (M-M), operation data that successively obtained by repeating a hash operation with a one-way hash function is assigned, so as to maintain hierarchical nature of scalability (L). A key generating unit generates partial keys (K-K) corresponding to respective hierarchies of the scalabilities (R, L), on the basis of the key element matrices (M-M). These partial keys (K-K) are outputted to a coding unit or a decoding unit by an output unit.

Encryption key generation device

The present invention relates to an image processing method and image inspecting method with high versatility which enable efficient and highly accurate proof of authenticity of a digital image. The image processing method subjects at least a part of a digital image which can exist temporarily or continuously in a falsification-vulnerable environment, to a first morphology operation using a predetermined structuring element, to process the digital image. The image inspecting method subjects the digital image thus processed, to a second morphology operation using the same structuring element as in the first morphology operation. The morphology operations have the idempotent and the presence or absence of falsification can be detected by determining identity of images before and after the second morphology operation.

Image processing method and image inspecting method

Growing community of inventors

Hino, Japan

Kiyoshi Nishikawa