JP2007020225A5 - - Google Patents

Claims (10)

A control method for an image data encryption device that encrypts image data using key information,
An input process for inputting image data having a hierarchical structure, in which data of each hierarchy can be specified by at least two parameters, and each parameter is expressed in multiple levels;
For the input image data, the key information for the data of the hierarchy specified by the two parameters originates from the key information for the data of the hierarchy specified by the two parameters at the maximum level. A generation step of generating key information using a predetermined one-way function that can be generated from any of the two pieces of key information for data in the hierarchy located one level higher;
The method of the previous SL in accordance with the key information generated by the generating step, the image data encryption apparatus, comprising an encryption step of encrypting the data hierarchy corresponding input in the input step.   The image data encryption according to claim 1, wherein the image data input in the input step is JPEG 2000 compression encoded data, and the parameters include tile, precinct, component, resolution, and layer. Control method. It said generating step, the control method of the image data encryption apparatus according to claim 1 or 2, characterized that you generate the key information according to the public key encryption method.   The method of controlling an image data encryption apparatus according to claim 1, wherein the generating step generates the key information by elliptic multiplication.   The method for controlling an image data encryption apparatus according to claim 1, wherein the one-way function used in the generation step is a hash function. An image data encryption device that encrypts image data using key information,
Input means for inputting image data having a hierarchical structure, in which data of each hierarchy can be specified by at least two parameters, and each parameter is expressed in multiple levels;
For the input image data, the key information for the data of the hierarchy specified by the two parameters originates from the key information for the data of the hierarchy specified by the two parameters at the maximum level. Generating means for generating key information using a predetermined one-way function that can be generated from any of the two pieces of key information for data in the hierarchy located one level higher;
An image data encryption apparatus comprising: an encryption unit configured to encrypt data of a corresponding layer input by the input unit according to the key information generated by the generation unit.   The image data according to claim 6, wherein the image data input by the input unit is JPEG 2000 compression encoded data, and the parameters include tile, precinct, component, resolution, and layer. Encryption device.   The image data encryption apparatus according to claim 6 or 7, wherein the one-way function used in the generation unit is a hash function. By computer executes read, a computer program to function as the image data encryption apparatus according to the computer in any one of claims 6 to 8.   A computer-readable storage medium storing the computer program according to claim 9.