Data player, digital contents player, playback system, data embedding apparatus, and embedded data detection apparatus

• US 7,120,251 B1
• Filed: 08/18/2000
• Issued: 10/10/2006
• Est. Priority Date: 08/20/1999
• Status: Expired due to Term

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Tatebayashi, Makoto, Katta, Noboru, Harada, Shunji, Ibaraki, Susumu, Kawada, Hirotsugu
• Primary Examiner(s): Song, Hosuk
• Assistant Examiner(s): Dada, Beemnet W
• Application Number:
  US09/640,783
• Time in Patent Office: 2,244 Days
• Field of Search: 713/193, 713/169, 713/171, 713/189, 380200-203, 380227-230
• US Class Current: 380/201
• CPC Class Codes: G11B 20/00086 Circuits for prevention of unauthorised reproduction or copying, e.g. piracy indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
• CPC Class Codes: G11B 20/00181 using a content identifier, e.g. an international standard recording code [ISRC] or a digital object identifier [DOI]
• CPC Class Codes: G11B 20/00195 using a device identifier associated with the player or recorder, e.g. serial numbers of playback apparatuses or MAC addresses
• CPC Class Codes: G11B 20/0021 involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 20/00231 wherein the key is obtained from a local external medium, e.g. a card
• CPC Class Codes: G11B 20/00673 wherein the erased or nullified data include a cryptographic key
• CPC Class Codes: G11B 20/0084 wherein the usage restriction can be expressed as a specific time or date
• CPC Class Codes: G11B 20/00884 involving a watermark, i.e. a barely perceptible transformation of the original data which can nevertheless be recognised by an algorithm
• CPC Class Codes: H04N 2005/91335 the copy protection signal being a watermark
• CPC Class Codes: H04N 2005/91364 the video signal being scrambled
• CPC Class Codes: H04N 21/2541 Rights Management protecting software against unauthorised usage in a vending or licensing environment G06F21/10; security in data switching network management H04L41/28; security management or policies for network security H04L63/20; access security in wireless networks H04W12/08
• CPC Class Codes: H04N 21/4181 for conditional access
• CPC Class Codes: H04N 21/42646 for reading from or writing on a non-volatile solid state storage medium, e.g. DVD, CD-ROM
• CPC Class Codes: H04N 21/4325 by playing back content from the storage medium reproduction of recorded television signals H04N5/76; reproduction of recorded television signals H04N9/79
• CPC Class Codes: H04N 21/4334 Recording operations recording of a television signal H04N5/76; arrangements for recording or accumulating broadcast information or broadcast-related information H04H60/27
• CPC Class Codes: H04N 21/4367 Establishing a secure communication between the client and a peripheral device or smart card
• CPC Class Codes: H04N 21/4405 involving video stream decryption
• CPC Class Codes: H04N 21/4408 involving video stream encryption, e.g. re-encrypting a decrypted video stream for redistribution in a home network
• CPC Class Codes: H04N 21/4623 Processing of entitlement messages, e.g. ECM [Entitlement Control Message] or EMM [Entitlement Management Message] arrangements for conditional access to broadcast information or to broadcast-related services H04H60/14
• CPC Class Codes: H04N 21/835 Generation of protective data, e.g. certificates protecting software against unauthorised usage in a vending or licensing environment G06F21/10
• CPC Class Codes: H04N 21/8358 : involving watermark protecting executable software by watermarking G06F21/16; image watermarking in general G06T1/0021; watermarks inserted in still images for transmission purposes H04N1/32144; inserting watermarks during video coding H04N19/467
• CPC Class Codes: H04N 5/85 : on discs or drums
• CPC Class Codes: H04N 5/913 : for scrambling ; for copy protection
• CPC Class Codes: H04N 7/1675 : Providing digital key or authorisation information for generation or regeneration of the scrambling sequence pseudo-random number generators in general G06F7/58
• CPC Class Codes: H04N 9/8042 : involving data reduction

Abstract

A data player for reading contents encrypted by a decoding key from a digital medium, and playing the encrypted contents by using the decoding key which is stored in a key storage unit, comprises: a key obtaining unit for performing mutual authentication with the key storage unit to obtain the decoding key stored in the key storage unit; a key holding unit for holding the decoding key; a playback state obtaining unit for monitoring the playback state of the digital medium; and a contents decoding unit for decoding the encrypted contents by using the decoding key. The decoding key is obtained by the key obtaining unit and stored in the key holding unit, and the encrypted contents read from the digital medium is decoded with the decoding key by the contents decoding unit to play the contents. The decoding key stored in the key holding unit is discarded according to the playback state of the digital medium which is obtained by the playback state obtaining unit.

Claims

1. A data player for reading contents encrypted by a decoding key from a digital medium, and playing the encrypted contents by using the decoding key which is stored in a key storage unit, said data player comprising:

key obtaining means for performing mutual authentication with the key storage unit to obtain the decoding key stored in the key storage unit;

key holding means for holding the decoding key;

playback state obtaining means for monitoring the playback state of the digital medium; and

contents decoding means for decoding the encrypted contents by using the decoding key;

wherein the decoding key is obtained by the key obtaining means and stored in the key holding means,

wherein the encrypted contents read from the digital medium is decoded with the decoding key by the contents decoding means to play the contents,

wherein the playback state obtaining means obtains the playback state of the digital medium, and

wherein the decoding key stored in the key holding means is discarded when it is confirmed that the playback state of the digital medium has changed.

2. The data player of claim 1, wherein the decoding key stored in the key holding means is discarded when it is confirmed that the playback state of the digital medium has become “

STOP STATE”

.

3. The data player of claim 1, wherein said digital medium is a DVD.

4. The data player of claim 2, wherein said digital medium is a DVD.

5. A data player for reading contents encrypted by a decoding key from a digital medium, and playing the encrypted contents by using the decoding key which is stored in a key storage unit, said data player comprising:

key obtaining means for performing mutual authentication with the key storage unit to obtain the decoding key stored in the key storage unit;

key holding means for holding the decoding key;

playback state obtaining means for monitoring the playback state of the digital medium; and

contents decoding means for decoding the encrypted contents by using the decoding key;

wherein the decoding key is obtained by the key obtaining means and stored in the key holding means,

wherein the encrypted contents read from the digital medium is decoded with the decoding key by the contents decoding means to play the contents,

wherein the playback state obtaining means obtains the playback state of the digital medium, and

wherein, if it is determined that the playback state of the digital recording medium has changed, then the decoding key stored in the key holding means is discarded.

6. The data player of claim 5, wherein the decoding key stored in the key holding means is discarded when it is determined that the playback state of the digital medium has become “

STOP STATE”

.

7. The data player of claim 5, wherein said digital medium is a DVD.

8. The data player of claim 6, wherein said digital medium is a DVD.