Methods and apparatuses for embedding digital watermark into and extracting digital watermark from text

Patent metadata

Field	Value
Publication number	US-9372968-B2
Application number	US-201314077613-A
Country	US
Kind code	B2
Filing date	Nov 12, 2013
Priority date	Jul 31, 2013
Publication date	Jun 21, 2016
Grant date	Jun 21, 2016

Abstract

Methods and apparatus for embedding digital watermark information into and extracting digital watermark information from a text are disclosed. The method for embedding digital watermark information into a text comprises: creating a menu item of the digital watermark information; and embedding a binary string into a value of a predetermined attribute for the menu item of the digital watermark information, the binary string to be embedded being the digital watermark information to be embedded. According to the present invention, it is able to increase the amount of information to be embedded.

First claim

What is claimed is:

1. a method for embedding digital watermark information into a text file by using a text processing device, the method comprising:
creating, for the text file, a menu item for the digital watermark information, wherein the menu item comprises a plurality of attribute and types of values of the attributes are binary strings: and
embedding a binary string into a value of a predetermined attribute of the menu item, the binary string to be embedded being the digital watermark information to be embedded;
wherein the text processing device is capable of programmatically customizing menu items of the text file and is capable of hiding the menu items for the text life.

2. The method according to claim 1 , wherein the step of embedding a binary string into a value of a predetermined attribute of the menu item comprises:
when the binary string to be embedded has a length greater than a predetermined length, dividing the binary string into several sub-strings, each of which has a length not greater than the predetermined length, the predetermined length being a maximum length of the value of the predetermined attribute of the menu item; and
setting the values of the predetermined attributes of the menu item as the sub-strings with a length not greater than the predetermined length respectively.

3. The method according to claim 1 , wherein the step of embedding a binary string into a value of a predetermined attribute of the menu item comprises:
when the binary string to be embedded has a length not greater than a predetermined length, setting a value of a predetermined attribute of the menu item as the binary string to be embedded, the predetermined length being a maximum length of the value of the predetermined attribute of the menu item.

4. The method according to claim 1 , further comprising:
selecting an information carrier character from a text content; and
embedding the binary string into a specified bit of a value of a predetermined attribute of the information carrier character, wherein the predetermined value for the information carrier character includes color of the character, underline color of the character and border color of the character.

5. The method according to claim 1 , wherein the binary string to be embedded is generated by:
generating a basic binary string according to predetermined original information;
generating a check string through a predetermined algorithm according to the basic binary string; and
generating the binary string to be embedded according to the basic binary string and the check string.

6. A method for extracting digital watermark information embedded through the method according to claim 1 , comprising the steps of:
determining a menu item; and
extracting a binary string from a value of a predetermined attribute of the menu item, the binary string to be extracted being the digital watermark information to be extracted.

7. The method according to claim 6 , wherein the step of extracting a binary string from a value of a predetermined attribute of the menu item comprises:
acquiring values of predetermined attributes of the menu item; and
determining the binary string to be extracted as an acquired binary string consisting of the acquired values.

8. The method according to claim 6 , wherein the step of extracting a binary string from a value of a predetermined attribute of the menu item comprises:
acquiring a value of a predetermined attribute of the menu item; and
determining the binary string to be extracted as the acquired value.

9. The method according to claim 6 , further comprising:
determining an information carrier character in the text content; and
extracting the binary string from a specified bit of a value of a predetermined attribute of the information carrier character, wherein the predetermined value for the information carrier character includes color of the character, underline color of the character and border color of the character.

10. The method according to claim 9 , further comprising:
determining whether or not the binary string extracted from the value of the predetermined attribute of the menu item is identical to the binary string extracted from the specified bit for the value of the predetermined attribute of the information carrier character.

11. The method according to claim 6 , further comprises:
determining a basic binary string and a check string according to the extracted binary string;
generating a check string through a predetermined algorithm according to the basic binary string; and
when the check string determined according to the extracted binary string is identical to the check string generated according to the basic binary string, determining original information corresponding to the basic binary string.

12. an apparatus for embedding digital watermark information into a text file, comprising:
a processor comprising;
a creation unit for creating, for the text file, a menu item for the digital watermark information, wherein the menu item comprises a plurality of attributes and types of values of the attributes are binary strings: and
a first embedment unit for embedding a binary string into a value of a predetermined attribute of the menu item, the binary string to be embedded being the digital watermark information to be embedded.
wherein the processor is capable of programmatically customizing menu items of the text file and is capable of hiding the menu items for the text file.

13. The apparatus according to claim 12 , wherein the first embedment unit, when the binary string to be embedded has a length greater than a predetermined length, divides the binary string into several sub-strings, each of which has a length not greater than the predetermined length, and sets the values of the predetermined attributes of the menu item as the sub-strings with a length not greater than the predetermined length respectively, wherein the predetermined length is a maximum length of the value of the predetermined attribute of the menu item.

14. The apparatus according to claim 12 , wherein the first embedment unit, when the binary string to be embedded has a length not greater than the predetermined length, sets a value of a predetermined attribute of the menu item as the binary string to be embedded, wherein the predetermined length is a maximum length of the value of the predetermined attribute of the menu item.

15. The apparatus according to claim 12 , the processor further comprising:
a selection unit for selecting an information carrier character from a text content; and
a second embedment unit for embedding the binary string into a specified bit for a value of a predetermined attribute of the information carrier character, wherein the predetermined attribute of the information carrier character includes color of the character, underline color of the character and border color of the character.

16. The apparatus according to claim 12 , the processor further comprising:
a generation unit for generating a basic binary string according to predetermined original information, for generating a check string through a predetermined algorithm according to the basic binary string, and for generating the binary string to be embedded according to the basic binary string and the check string.

17. An apparatus for extracting the digital watermark information embedded by the apparatus according to claim 12 , comprising:
a processor comprising:
a first determination unit for determining a menu item of the digital watermark information; and
a first extraction unit

Assignees

• Univ Peking Founder Group Co
• Founder Information Industry Group
• Beijing Founder Electronics Co
• Perking University Founder Group Co Ltd

Inventors

• Feng Hui

Classifications

• G06F21/16 Primary

  Program or content traceability, e.g. by watermarking · CPC title