IMAGE ENCRYPTING DEVICE, IMAGE DECRYPTING DEVICE AND METHOD
First Claim
1. An image encrypting device for encrypting an image, comprising:
- input means for inputting image data to be encrypted;
encryption region specifying means for specifying a region to be encrypted in the image data input by the input means;
image converting means for converting the encryption region, which is specified by the encryption region specifying means, into a first image by using an encryption key;
public key obtaining means for obtaining a public key of a transmission destination of the data to be encrypted;
key encrypting means for encrypting the encryption key by using the public key obtained by the public key obtaining means;
information embedding means for embedding encryption key associated information, which is information about the encryption key encrypted by the key encrypting means, in the first image to convert the encryption region into a second image;
pixel value converting means for converting a pixel value of the second image to convert the encryption region into a third image so that the region specified by the encryption region specifying means is identifiable; and
output means for outputting an encrypted image, which is obtained by converting an image of the encryption region into the third image in the image input by the input means, in a predetermined method.
1 Assignment
0 Petitions
Accused Products
Abstract
An encrypting device generates an encrypted image by converting an image of a specified region in an input image with an encryption key, by embedding information obtained by encrypting the encryption key with a public key pairing with the private key of a destination, and by performing pixel value conversion. Then, the encrypted image is transmitted to the destination as a printed matter or via a network. A decrypting device converts the encrypted image in the form of print data or electronic data into an image, and inputs it. Next, the decrypting device extracts a decryption key (the encryption key) from the image of the encryption region by executing a process reverse to that of the encrypting device for the encryption region of the converted encrypted image. Then, the decrypting device decrypts the original image of the encrypted region by using the decryption key, and restores the entire encrypted image.
223 Citations
25 Claims
-
1. An image encrypting device for encrypting an image, comprising:
-
input means for inputting image data to be encrypted; encryption region specifying means for specifying a region to be encrypted in the image data input by the input means; image converting means for converting the encryption region, which is specified by the encryption region specifying means, into a first image by using an encryption key; public key obtaining means for obtaining a public key of a transmission destination of the data to be encrypted; key encrypting means for encrypting the encryption key by using the public key obtained by the public key obtaining means; information embedding means for embedding encryption key associated information, which is information about the encryption key encrypted by the key encrypting means, in the first image to convert the encryption region into a second image; pixel value converting means for converting a pixel value of the second image to convert the encryption region into a third image so that the region specified by the encryption region specifying means is identifiable; and output means for outputting an encrypted image, which is obtained by converting an image of the encryption region into the third image in the image input by the input means, in a predetermined method. - View Dependent Claims (2, 3, 4, 5)
-
-
6. An image decrypting device for decrypting an encrypted image including an image encrypted into an original image, comprising:
-
input means for inputting the encrypted image as image data; encryption position detecting means for detecting a position of an encryption region that is a region, in which an image is encrypted in the encrypted image, by analyzing the encrypted image input by the input means; pixel value converting means for restoring a pixel value of the image of the encryption region to a pixel value before being converted in order to identify the position of the encryption region on the basis of information about the position of the encryption region detected by the encryption position detecting means; information extracting means for extracting encryption key associated information, which is information about an encryption key embedded in the image of the encryption region, from the image of the encryption region, which is generated by the pixel value converting means; key decrypting means for decrypting a decryption key, which is used to decrypt the image of the encryption region, from the encryption key associated information by using a first private key pairing with a first public key used to generate the encryption key associated information extracted by the information extracting means; image converting means for decrypting an original image by decrypting the image of the encryption region by using the decryption key decrypted by the key decrypting means; and output means for outputting the original image in a predetermined method. - View Dependent Claims (7, 8, 9, 10)
-
-
11. An image encrypting method for encrypting an image, comprising:
-
a step of inputting image data to be encrypted; a step of specifying a region to be encrypted in the image data input by the input step; a step of converting the specified encryption region into a first image by using an encryption key; a step of obtaining a public key of a transmission destination of the data to be encrypted; a step of encrypting the encryption key by using the obtained public key; a step of embedding encryption key associated information, which is information about the encrypted encryption key, in the first image to convert the encryption region into a second image; a step of converting a pixel value of the second image to convert the encryption region into a third image so that the region specified to be encrypted is identifiable; and a step of outputting an encrypted image, which is obtained by converting an image of the encryption region into the third image in the input image to be encrypted, in a predetermined method. - View Dependent Claims (12, 13)
-
-
14. An image decrypting method for decrypting an encrypted image including an image encrypted into an original image, comprising:
-
a step of inputting the encrypted image as image data; a step of detecting a position of an encryption region that is a region, in which an image is encrypted in the encrypted image, by analyzing the encrypted image input by the input step; a step of restoring a pixel value of the image of the encryption region to a pixel value before being converted in order to identify the position of the encryption region on the basis of information about the detected position of the encryption region; a step of extracting encryption key associated information, which is information about an encryption key embedded in the image of the encryption region, from the image of the encryption region generated by the pixel value converting step; a step of decrypting a decryption key, which is used to decrypt the image of the encryption region, from the encryption key associated information by using a first private key pairing with a first public key used to generate the extracted encryption key associated information; a step of decrypting the original image by decrypting the image of the encryption region by using the decrypted decryption key; and a step of outputting the original image in a predetermined method. - View Dependent Claims (15, 16, 17)
-
-
18. A storage medium storing an image encrypting program for causing a computer, in order to encrypt an image, to operate as:
-
input means for inputting image data to be encrypted; encryption region specifying means for specifying a region to be encrypted in the image input by the input means; image converting means for converting the encryption region specified by the encryption region specifying means into a first image by using an encryption key; public key obtaining means for obtaining a public key of a transmission destination of the data to be encrypted; key encrypting means for encrypting the encryption key by using the public key obtained by the public key obtaining means; information embedding means for embedding encryption key associated information, which is information about the encryption key encrypted by the key encrypting means, in the first image to convert the encryption region into a second image; pixel value converting means for converting a pixel value of the second image to convert the encryption region into a third image so that the region specified by the encryption region specifying means is identifiable; and output means for outputting an encrypted image, which is obtained by converting an image of the encryption region into the third image in the image input by the input means, in a predetermined method. - View Dependent Claims (19, 20, 21)
-
-
22. A storage medium storing an image decrypting program for causing a computer, in order to decrypt an encrypted image including an image encrypted into an original image, to operate as:
-
input means for inputting the encrypted image as image data; encryption position detecting means for detecting a position of an encryption region that is a region, in which an image is encrypted in the encrypted image, by analyzing the encrypted image input by the input means; pixel value converting means for restoring a pixel value of an image of the encryption region to a pixel value before being converted in order to identify the position of the encryption region on the basis of information about the position of the encryption region detected by the encryption position detecting means; information extracting means for extracting encryption key associated information, which is information about an encryption key embedded in the image of the encryption region, from the image of the encryption region generated by the pixel value converting means; key decrypting means for decrypting a decryption key, which is used to decrypt the image of the encryption region, from the encryption key associated information by using a first private key pairing with a first public key used to generate the encryption key associated information extracted by the information extracting means; image converting means for decrypting the original image by decrypting the image of the encryption region by using the decryption key decrypted by the key decrypting means; and means for outputting the original image in a predetermined method. - View Dependent Claims (23, 24, 25)
-
Specification