Countermeasure against estimation-based attacks of spread-spectrum watermarks

• US 7,389,421 B2
• Filed: 04/18/2002
• Issued: 06/17/2008
• Est. Priority Date: 04/18/2002
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Kirovski, Darko, Malvar, Henrique
• Primary Examiner(s): Moise, Emmanuel L
• Assistant Examiner(s): Khoshnoodi, Nadia
• Application Number:
  US10/127,029
• Publication Number:
  US 20030200438A1
• Time in Patent Office: 2,252 Days
• Field of Search: 713/176
• US Class Current: 713/176
• CPC Class Codes: G06T 1/005 Robust watermarking, e.g. average attack or collusion attack resistant
• CPC Class Codes: G06T 2201/0065 Extraction of an embedded watermark; Reliable detection
• CPC Class Codes: H04N 1/00002 Diagnosis, testing or measuring; Detecting, analysing or monitoring not otherwise provided for error detection, error correction or monitoring in digital computers or digital computer components G06F11/00
• CPC Class Codes: H04N 1/00005 relating to image data
• CPC Class Codes: H04N 1/00037 Detecting, i.e. determining the occurrence of a predetermined state H04N1/00031 takes precedence
• CPC Class Codes: H04N 1/00068 Calculating or estimating

Abstract

Described herein is a technology for facilitating watermark detection. Spread-spectrum watermarking is a commonly employed technique for hiding data in digital goods (e.g., multimedia signals). Such watermarks may be potentially vulnerable to so-called “watermark estimation-based attacks.” At least one implementation, described herein, is an advancement over the traditional spread-spectrum watermark detector. At least one implementation, described herein, greatly discourages an estimation-based attack by an adversary. At least one implementation, described herein, determines whether a digital good has likely been subjected to an estimation-based attack and, at least, approximately reverses such attack. The scope of the present invention is pointed out in the appending claims.

Claims

1. A computer storage medium having computer-executable instructions that, when executed by a computer, performs a method facilitating a watermark estimation-based attack countermeasure, the method comprising:

facilitating the watermark estimation-based attack countermeasure by;

obtaining a digital good, which comprises digital content embodied on one or more computer-readable media, wherein the digital good is not just a watermark;

analyzing the digital good to determine that such digital good was subjected to a watermark estimation-based attack, in response to determining that such digital good was subjected to a watermark estimation-based attack performing a countermeasure comprising;

determining an estimated attack-amplification value α

likely employed by a watermark estimation-based attack on the digital good;

producing an approximation of the digital good before it was subjected to the watermark estimation-based attack, whereby the produced approximation of the digital good facilitates a countermeasure to a watermark estimation-based attack, wherein the producing comprises;

identifying portions of a probability distribution function (PDF) of the digital good that remain unchanged after the watermark estimation-based attack on the digital good;

shifting the identified portions of the PDF of the digital good by the estimated attack-amplification value α

; and

determining the remainder of the PDF between the portions.

2. A medium as recited in claim 1 further comprising providing the approximated pre-attack digital good for watermark detection.

3. A computer storage medium having computer-executable instructions that, when executed by a computer, performs a method facilitating a watermark estimation-based attack countermeasure, the method comprising:

obtaining a digital good, which had been subjected to a watermark estimation-based attack, wherein the digital good comprises digital content embodied on one or more computer-readable media, wherein the digital good is not just a watermark;

determining an estimated attack-amplification value α

;

producing an approximation of the digital good before it was subjected to the watermark estimation-based attack, whereby the produced approximation of the digital good facilitates a countermeasure to a watermark estimation-based attack, wherein the producing comprises;

identifying portions of a probability distribution function (PDF) of the digital good that remain unchanged after the watermark estimation-based attack on the digital good;

shifting the identified portions of the PDF of the digital good by the estimated attack-amplification value α

;

determining remainder of the PDF between the portions.

4. A medium as recited in claim 3 further comprising analyzing the digital good to determine whether such digital good was subjected to a watermark estimation-based attack.

5. A medium as recited in claim 3 further comprising providing the approximated pre-attack digital good for watermark detection.

6. A method facilitating a watermark estimation-based attack countermeasure, the method comprising:

obtaining a digital good, which had been subjected to a watermark estimation-based attack, wherein the digital good comprises digital content embodied on one or more computer-readable media, wherein the digital good is not just a watermark;

determining an estimated attack-amplification value α

;

producing an approximation of the digital good before it was subjected to the watermark estimation-based attack, whereby the produced approximation of the digital good facilitates a countermeasure to a watermark estimation-based attack, wherein the producing comprises;

identifying portions of a probability distribution function (PDF) of the digital good that remain unchanged after the watermark estimation-based attack on the digital good;

shifting the identified portions of the PDF of the digital good by the estimated attack-amplification value α

;

determining remainder of the PDF between the portions.

7. A method as recited in claim 6 further comprising analyzing the digital good to determine whether such digital good was subjected to a watermark estimation-based attack.

8. A method as recited in claim 6 further comprising providing the approximated pre-attack digital good for watermark detection.

9. A watermark detection system comprising:

a memory comprising a set of computer program instructions; and

a processor coupled to the memory, the processor being configured to execute the computer program instructions facilitating a watermark estimation-based attack countermeasure, such instructions that when executed by a processor perform a method comprising;

obtaining a digital good, which had been subjected to a watermark estimation-based attack, wherein the digital good comprises digital content embodied on one or more computer-readable media, wherein the digital good is not just a watermark;

determining an estimated attack-amplification value α

;

producing an approximation of the digital good before it was subjected to the watermark estimation-based attack, whereby the produced approximation of the digital good facilitates a countermeasure to a watermark estimation-based attack, wherein the producing comprises;

identifying portions of a probability distribution function (PDF) of the digital good that remain unchanged after the watermark estimation-based attack on the digital good;

shifting the identified portions of the PDF of the digital good by the estimated attack-amplification value α

;

determining remainder of the PDF between the portions.

10. A system as recited in claim 9, wherein the instructions further comprise analyzing the digital good to determine whether such digital good was subjected to a watermark estimation-based attack.

11. A system as recited in claim 9, wherein the instructions further comprise providing the approximated pre-attack digital good for watermark detection.