Copy detection for digitally-formatted works

• US 6,868,405 B1
• Filed: 11/29/1999
• Issued: 03/15/2005
• Est. Priority Date: 11/29/1999
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: DeTreville, John
• Primary Examiner(s): Trammell, James P.
• Assistant Examiner(s): WINTER, JOHN M
• Application Number:
  US09/451,253
• Time in Patent Office: 1,933 Days
• Field of Search: 705/56, 705/58, 380/243, 713/1
• US Class Current: 705/58
• CPC Class Codes: G06F 21/10 Protecting distributed programs or content, e.g. vending or licensing of copyrighted material protection in video systems or pay television H04N7/16 ; Digital rights management [DRM]
• CPC Class Codes: G06F 21/16 Program or content traceability, e.g. by watermarking
• CPC Class Codes: G06Q 30/018 Certifying business or products
• CPC Class Codes: H04L 2463/101 applying security measures for digital rights management data processing systems or methods, specially adapted for commerce, e.g. marketing, shopping, billing, auctions or e-commerce G06Q30/00
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/101 Access control lists [ACL]

Abstract

An electronic book reader has a processor, a display surface, and access to a memory card upon which is stored a digitally-formatted creative work such as a book. In addition, the reader has access to a plurality of precompiled condensed content descriptions of respective books that are subject to copy restrictions. Before reading a given book, the reader creates a condensed content description of the book and compares it to the stored descriptions to determine whether the book is subject to copy restrictions. If it is, the reader checks for a valid license before allowing the user to read the book.

Claims

1. An electronic book reader, comprising:

a display surface;

a receptacle that accepts a digital storage device containing a digitally-formatted book;

a data store containing precompiled condensed content descriptions of respective books that are subject to copy restrictions;

one or more data processors that read the digitally-formatted book from the digital storage device and that display the book on the display surface;

wherein the one or more data processors create a condensed content description of the digitally-formatted book and compare the created condensed content description with the precompiled condensed content descriptions to determine whether the digitally-formatted book is subject to copy restrictions; and

wherein if the digitally-formatted book is determined to be subject to copy restrictions, the one or more data processors determine whether the digitally-formatted book is authorized.

2. An electronic book reader as recited in claim 1, wherein:

the electronic book reader downloads digitally-formatted books from one or more authorized sources; and

the electronic book reader also downloads one or more of the precompiled condensed content descriptions when downloading the books.

3. An electronic book reader as recited in claim 1, wherein condensed content description corresponding to any given digitally-formatted book is a list of hash values, each hash value being calculated from a portion of the given digitally-formatted book.

4. An electronic book reader as recited in claim 1, wherein condensed content description corresponding to any given digitally-formatted book is a list of hash values, each hash value being calculated from a portion of the given digitally-formatted book using a hash function that changes over time.

5. An electronic book reader as recited in claim 1, wherein:

the digitally-formatted books contain grammatical text;

the condensed content description corresponding to any given digitally-formatted book is a list of hash values; and

each hash value is calculated from a sequence of words that occurs in the given digitally-formatted book.

6. An electronic book reader as recited in claim 1, wherein:

the digitally-formatted books contain grammatical text;

the condensed content description corresponding to any given digitally-formatted book is a list of hash values;

each hash value is calculated from a sequence of words that occurs in the given digitally-formatted book; and

each sequence of words contains at least 100 characters.

7. An electronic book reader as recited in claim 1, wherein:

the digitally-formatted books contain grammatical text;

the condensed content description corresponding to any given digitally-formatted book is a list of hash values; and

the hash values are calculated in a way that allows comparison of ordered word sequences in the digitally-formatted books.

8. An electronic book system, comprising:

a distribution server;

a plurality of electronic book readers that download digitally-formatted books from the distribution server;

wherein the electronic book readers also download sets of condensed content descriptions when downloading digitally-formatted books, wherein the condensed content descriptions are of respective books subject to copy restrictions;

wherein a particular electronic book reader creates a condensed content description of a particular digitally-formatted book when reading said digitally-formatted book, and compares the created condensed content description with the downloaded set of content descriptions to determine whether said particular digitally-formatted book is subject to copy restrictions; and

wherein if the digitally-formatted book is determined to be subject to copy restrictions, the electronic book reader determines whether said particular digitally-formatted book is authorized.

9. An electronic book system as recited in claim 8, wherein:

there are a plurality of available condensed content descriptions; and

the electronic book readers download different sets of the plurality of condensed book descriptions.

10. An electronic book system as recited in claim 8 wherein:

there are a plurality of available condensed content descriptions; and

any particular electronic book reader downloads a different set of the plurality of condensed book descriptions each time it downloads a digitally-formatted book.

11. An electronic book system as recited in claim 8, wherein the condensed content description of any given digitally-formatted book is a list of hash values, each hash value being calculated from a portion of the given digitally-formatted book.

12. An electronic book system as recited in claim 8, wherein the condensed content description of any given digitally-formatted book is a list of hash values, each hash value being calculated from a portion of the given digitally-formatted book using a hash function that changes over time.

13. An electronic book system as recited in claim 8, wherein:

the digitally-formatted books contain grammatical text;

the condensed content description corresponding to any given digitally-formatted book is a list of hash values; and

each hash value is calculated from a sequence of words that occurs in the given digitally-formatted book.

14. An electronic book system as recited in claim 8, wherein:

the digitally-formatted books contain grammatical text;

the condensed content description corresponding to any given digitally-formatted book is a list of hash values;

each hash value is calculated from a sequence of words that occurs in the given digitally-formatted book; and

each sequence of words contains at least 100 characters.

15. An electronic book system as recited in claim 8, wherein:

the digitally-formatted books contain grammatical text;

the condensed content description corresponding to any given digitally-formatted book is a list of hash values; and

the hash values are calculated in a way that allows comparison of ordered word sequences in the digitally-formatted books.

16. A method of detecting violation of copy restrictions comprising:

receiving precompiled condensed content descriptions of digitally-formatted works that are subject to copy restrictions;

in conjunction with reading a particular digitally-formatted work for perception by a user, creating a condensed content description of said particular digitally-formatted work; and

comparing the created condensed content description to the precompiled condensed content descriptions to determine whether said particular digitally-formatted work is subject to copy restrictions.

17. A method as recited in claim 16, wherein the condensed content description corresponding to any given digitally-formatted work is a list of hash values, each hash value being calculated from a portion of the given digitally-formatted work using a hash function, the method further comprising changing the hash function over time.

18. A method as recited in claim 16, wherein:

the digitally-formatted works contain grammatical text;

the condensed content description corresponding to any given digitally-formatted work is a list of hash values; and

each hash value is calculated from a sequence of words that occurs in the given digitally-formatted work.

19. A method as recited in claim 16, wherein:

the digitally-formatted works contain grammatical text;

the condensed content description corresponding to any given digitally-formatted work is a list of hash values;

each hash value is calculated from a sequence of words that occurs in the given digitally-formatted work; and

each sequence of words contains at least 100 characters.

20. A method as recited in claim 16, wherein:

the digitally-formatted works contain grammatical text;

the condensed content description corresponding to any given digitally-formatted work is a list of hash values; and

the hash values are calculated in a way that allows comparison of ordered word sequences in the digitally-formatted works.