Patent ID: 7937766
Filing Date: 2011-05-03
Classification: H04N

Abstract:
1. A storage device for recording contents, the contents comprising a first content and a second content, the storage device comprising: a first storage area in which the contents are recorded; and a second storage area limited for access, wherein the first storage area records therein a first encrypted content obtained by encrypting the first content by using a predetermined encryption key, and a second encrypted content obtained by encrypting the second content, the second content being generated by executing a predetermined conversion process on the first content, and the second content being encrypted by using the predetermined encryption key used for encrypting the first content, wherein the second storage area records therein first license information regarding the first content and the second content, wherein the first license information contains first use period information indicating a first use period during which use of one of the first content and the second content is permitted, and a content key for decrypting the first encrypted content and the second encrypted content, and wherein the storage device is configured to: change the first license information so that the second use period during which the use of the second encrypted content output to the external storage medium is permitted is excluded from the first use period during which the use of the one of the first content and the second content stored in the storage device is permitted; and set the second use period during which the use of the second encrypted content output to the external storage medium is permitted such that the second use period does not overlap with the first use period during which the use of the one of the first content and the second content stored in the storage device is permitted.