Patent ID: 8588414

Claim:
An image encryption apparatus encrypting an image, comprising: a central processing unit; and a computer-readable recording medium having stored therein a program for causing the central processing unit to execute processes, the processes including: obtaining input data, performing format conversion of the obtained input data into an image as needed, and inputting the image to be a target of encryption; specifying, with regard to an image obtained by the obtaining, a region to be encrypted; converting an image in the encryption region specified by the specifying into a first intermediate image on a basis of an encryption key; generating encryption key-related information on a basis of the encryption key; embedding the encryption key-related information generated by the generating into the first intermediate image to generate a second intermediate image; performing pixel value conversion for the second intermediate image generated by the embedding; and outputting the image after the pixel value conversion while performing format conversion of the image as needed, wherein the embedding embeds the encryption key-related information into the image in the encryption region by converting pixel values of the image in the encryption region on a basis of the encryption key-related information.