摘要:
When image data in which a digital watermark is embedded accesses a server, particularly, a Web server, via a network, the server is appropriately selected and accessed via the network in accordance with the environments of the clients that access the server. A network access terminal includes an extraction unit for extracting first information from an image that includes the first information, which is multi-valued, an acquisition unit for acquiring from a predetermined storage device the first information extracted by the extraction unit and address information specified by second information different from the first information, from among a plurality of address information stored in the predetermined storage device, and a communication unit for accessing an address based on the address information obtained by the acquisition unit.
摘要:
An encryption technique and a decryption technique that are applied to video data that is encrypted on a predetermined domain of compressed video data are disclosed. For example, JPEG2000 compressed video data can be compressed using a wavelet conversion. Compressed video data is input. The input video data is decompressed to a predetermined domain of the compression process, and the decompressed video data is then encrypted. The encrypted video data is then compressed in accordance with the decompression process, and information representing the encrypted compression domain is stored in a predetermined area of the compressed video data.
摘要:
In an image process apparatus, a key different for each level of hierarchy is generated on the basis of a specific key with respect to image data having a hierarchical structure, the image data in each level of the hierarchy is encrypted using the generated key for each level, and the specific key is managed, so that key management can be easily performed while the image data having a hierarchical structure is enciphered using different keys for each level of the hierarchy.
摘要:
The present invention aims to provide the technique of appropriately enabling the encryption and decryption to the partial area with respect to the image data to which the partial encryption and the multiple encryptions have been applied. More specifically, the predetermined image area in the image data is acquired by a reproduction area designation unit, the overlap area of the acquired image area and the encrypted encryption area is calculated by an overlap judgment unit, the key information corresponding to the calculated overlap area is acquired by a decryption key acquisition unit, and the image data corresponding to the overlap area is acquired by a decryption key acquisition unit, and the image data corresponding to the overlap area is subjected to the encryption and decryption by an image decryption unit by using the acquired key information.
摘要:
This invention allows the encryption side to set whether an image playback apparatus should play back image data in a scrambled state or a non-scrambled state. When a code-block of input image data is an object to be encrypted, it is encrypted. In playing back the data, it is determined whether playback is to be executed by using the encrypted code-block (the scrambling playback mode is to be set). To inhibit use of the encrypted code-block, a terminating marker is placed at the start of the code-block. To use the encrypted code-block, the terminating marker is placed at the end of the code-block.
摘要:
An object of the present invention is to provide a technique by which machines can determine whether printed material is an original or a copy. A technique for outputting printed material which has an effect similar to that of security paper using normal paper instead of specially printed paper such as the security paper is provided. An image-processing apparatus generates a new image by expressing a latent image area with dots of a first dot size and a background area with dots of a second dot size which is different from the first dot size, and generates another image by moving each of the dots included in the latent image area in accordance with a bit value at the corresponding bit position in additional information.
摘要:
An information processing apparatus that generates private information used as one of an encryption key for encrypting data or a generation key for generating falsification detection information used in detecting falsification of data, comprises a storage unit adapted to prestore key information, an input unit adapted to input calculation target information, a calculating unit adapted to perform a calculation on targeted information based on the key information held in the storage unit, a detecting unit adapted to detect a predetermined event, and a control unit adapted, when triggered by detection of the event by the detecting unit, to perform controls to generate the private information by making the calculating unit perform the calculation with the input calculation target information as the targeted information, and to place the key information stored in the storage unit in an unusable state.
摘要:
Upon applying a DRM protection process to an image which is generated by an image processing apparatus, which doesn't have any communication means that allows direct communications with a PC, without any alteration, encryption of the image in the apparatus and that of the image in the PC as an internal process of the DRM are required, resulting in poor efficiency. The apparatus executes a part of the DRM protection process for the image, and outputs the encrypted image. The PC receives the image which has undergone the part of the DRM protection process, executes the remaining part of the DRM protection process, and outputs the image which has undergone the DRM protection process. In this case, the PC transmits use condition of the input image to a license server, receives signed use condition from the server, and combines the signed use condition with the input encrypted image.
摘要:
It is possible to safely constitute a key management method having an access structure equivalent to the hierarchical key management method with a small amount of calculations. The method includes: a setting step for setting a set (,) of the number of times a one-way hash function is executed for each of the elements of the rank i; a key generation step for generating two separate keys for the elements as the value of the number of times the one-way function has been executed corresponding to the set of the number of times which has been set for the elements of the two original keys for each of the elements; and a key delivery step for delivering the two separate keys for the elements to each of the elements. Furthermore, the method includes an initial key generation step for calculating N keys with a route node positioned at the most significant node when generating a key at each node from a parent node and performing key delivery according to the hierarchical relationship expressed in a directed graph having no cycle; and a node key generation step for generating the value of the number of predetermined times the one-way function is executed according to the execution specification for M keys (M≦N) among the N initial keys in each node, as the M node keys for the node.
摘要:
This invention reduces degradation in image quality and improves altered portion specifying accuracy in a digital watermark technology. For this purpose, an apparatus of this invention inputs image data and information such as a copyright holder name to be embedded in the image data (S1, S2). A mask pattern having a blue noise characteristic for intermediate- and high-frequency components is set at the image data start position, and pixel data at a target embedding position in the mask pattern is quantized (S5). The quantization error at this time corresponds to the bit information to be embedded at that position. This processing is repeatedly performed for the entire image (S6-S9).