Method for hiding a binary encoded message in an electronic document by modulating the case of the characters in a case-insensitive markup language

• US 5,920,878 A
• Filed: 11/14/1996
• Issued: 07/06/1999
• Est. Priority Date: 11/14/1996
• Status: Expired due to Fees

• Current Assignee: Achates Reference Publishing Incorporated
• Original Assignee: Jason Paul Demont
• Inventors: DeMont, Jason Paul
• Primary Examiner(s): Powell, Mark R.
• Assistant Examiner(s): Rossi, Jeffrey Allen
• Application Number:
  US08/748,777
• Time in Patent Office: 964 Days
• Field of Search: 707/500, 707/513, 707/531, 380/4, 380/23, 380/25, 283/72
• US Class Current: 715/236
• CPC Class Codes: G06F 40/123 Storage facilities

Abstract

Embodiments of the present invention are capable of hiding a message, such as, for example, a copyright notice or other indicium of authorship, in an electronic document. An illustrative embodiment of the present invention comprises encoding an electronic document with a plurality of tags from a case insensitive markup language; and modulating the case of at least one tag character in at least one of said plurality of tags with a binary string, wherein the binary string represents a message to be hidden in the electronic document.

Claims

1. A method comprising:

encoding an electronic document with a plurality of tags from a case insensitive markup language; and

modulating the case of at least one tag character in at least one of said plurality of tags with a binary string, wherein said binary string represents a message to be hidden in said electronic document.

2. The method of claim 1 further comprising encoding said binary string with error correction.

3. The method of claim 1 wherein said message represents text.

4. The method of claim 1 wherein said message is a copyright notice.

5. A method comprising:

encoding an electronic document with a plurality of tags from a case insensitive markup language;

reducing a message to be hidden in said electronic document to a binary string;

selecting a nonempty subset of said plurality of tags; and

modulating the case of said nonempty subset of said plurality of tags with said binary string.

6. The method of claim 5 further comprising encoding said binary string with error correction.

7. The method of claim 5 wherein said message represents text.

8. The method of claim 5 wherein said message is a copyright notice.

9. A method of recovering a message hidden in an electronic document comprising:

demodulating the case of at least one tag character in at least one of a plurality of tags in said electronic document to recover a binary string, wherein said plurality of tags are from a case insensitive markup language; and

converting said binary string into said hidden message.

10. The method of claim 9 further comprising correcting said binary string with an error correction code.