Patent ID: 8325917
Filing Date: 2012-12-04
Classification: G11B,H04N

Abstract:
1. A reproducing device for reproducing content data for content recorded on a recording medium, the content including a plurality of pieces of original partial data, and the content data including a plurality of original packets, at least one transformed packet and at least one restoration-use packet, the at least one transformed packet corresponding to one of the plurality of pieces of original partial data, each of the plurality of original packets corresponding to any one of the plurality of pieces of original partial data other than the one piece of original partial data corresponding to the least one transformed packet, the at least one transformed packet including transformed or altered data, each of the plurality of original packets including a corresponding one of the plurality of pieces of original partial data as-is, the at least one transformed packet including (i) the one piece of the original partial data corresponding thereto as-is except a target part which is a part of the one piece of the original partial data corresponding thereto, and (ii) a transformed part instead of the target part, the transformed part being generated by encrypting the target part, the reproducing device comprising: a device unique information storage unit operable to store device unique information for uniquely identifying the reproducing device, the device unique information storing unit being a non-transitory memory for storing the device unique information; an acquisition unit operable to acquire the content data from the recording medium; an extraction unit operable to extract a piece of restoration information from the at least one restoration-use packet constituting the acquired content data, the least one restoration-use packet being positioned a relative packet count before the at least one transformed packet in the content data, and the at least one restoration-use packet including a piece of restoration information including a relative packet count, an in-packet position, a restoration-use parameter and a restoration instruction flag; a position specification unit operable to specify, as the at least one transformed packet, a packet positioned the relative packet count included in the extracted piece of restoration information after the at least one restoration-use packet, and specify the position of the transformed part in the at least one transformed packet based on the in-packet position included in the extracted piece of restoration information; a restoration unit operable to judge which of the following the restoration instruction flag indicates: (a) the restoration processing is performed, (b) the restoration processing is not performed, and (c) the restoration processing is performed depending on the device unique information, and (i) when the judging indicates that (a) the restoration processing is performed, perform the restoration processing of replacing part of the content data with the restoration-use parameter on the specified position, (ii) when the judging indicates that (b) the restoration processing is not performed, not to perform the restoration processing, and (iii) when the judging indicates that (c) the restoration processing is performed depending on the device unique information, perform the restoration processing depending on the device unique information for uniquely identifying the reproducing device on the specified position; and a reproducing unit operable to reproduce the content data,