Derivation and quantization of robust non-local characteristics for blind watermarking

• US 20050125671A1
• Filed: 12/15/2004
• Published: 06/09/2005
• Est. Priority Date: 04/24/2001
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Venkatesan, Ramarathnam, Jakubowski, Mariusz H., Mihcak, M. Kivanc
• Granted Patent: US 7,634,660 B2
• Time in Patent Office: Days
• US Class Current: 713/176
• CPC Class Codes: G06F 21/16 Program or content traceability, e.g. by watermarking
• CPC Class Codes: G06T 1/005 Robust watermarking, e.g. average attack or collusion attack resistant
• CPC Class Codes: G06T 2201/0052 Embedding of the watermark in the frequency domain
• CPC Class Codes: G06T 2201/0065 Extraction of an embedded watermark; Reliable detection
• CPC Class Codes: G06T 2201/0083 whereby only watermarked image required at decoder, e.g. source-based, blind, oblivious
• 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 63/1441 Countermeasures against malicious traffic countermeasures against attacks on cryptographic mechanisms H04L9/002
• CPC Class Codes: H04N 1/32144 embedded in the image data, i.e. enclosed or integrated in the image, e.g. watermark, super-imposed logo or stamp
• CPC Class Codes: H04N 1/32149 Methods relating to embedding, encoding, decoding, detection or retrieval operations
• CPC Class Codes: H04N 1/32154 Transform domain methods H04N1/32309 takes precedence
• CPC Class Codes: H04N 1/3217 using wavelet transforms
• CPC Class Codes: H04N 1/32187 with selective or adaptive application of the additional information, e.g. in selected frequency coefficients
• CPC Class Codes: H04N 1/32277 Compression
• CPC Class Codes: H04N 1/3232 Robust embedding or watermarking
• CPC Class Codes: H04N 1/32341 Blind embedding, i.e. the original image not being known beforehand
• 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 2201/3233 of authentication information, e.g. digital signature, watermark
• CPC Class Codes: H04N 2201/327 which are undetectable to the naked eye, e.g. embedded codes

Abstract

An implementation of a technology is described herein for deriving robust non-local characteristics and quantizing such characteristics for blind watermarking of a digital good. This technology finds the proper balance between minimizing the probability of false alarms (i.e., detecting a non-existent watermark) and the probability of misses (i.e., failing to detect an existing watermark). The technology, described herein, performs quantization index modulation (QIM) based upon non-local characteristics of the digital good. Non-local characteristics may include statistics (e.g., averages, median) of a group of individual parts (e.g., pixels) of a digital good. This abstract itself is not intended to limit the scope of this patent. The scope of the present invention is pointed out in the appending claims.

Claims

1. A method facilitating protection of digital signals, the method comprising:

partitioning a digital signal into segments;

for one or more segments;

calculating statistics of a segment that are representative of that segment;

quantizing such statistics of a segment;

generating a marked signal equivalent to a combination of the digital signal and the combination of the quantized statistics of the one or more segments.

2. A method as recited in claim 1 further comprising normalizing amplitude of a digital signal, wherein such signal is an original, unmarked signal.

3. A method as recited in claim 1 further comprising transforming the signal.

4. A method as recited in claim 1, wherein the statistics of the calculating comprises one or more finite order moments of a segment.

5. A method as recited in claim 1 further comprising determining a delta-sequence that is representative of the combination of the quantized statistics of the one or more segments.

6. A method as recited in claim 1 further comprising determining a pseudorandom delta-sequence that when combined with the digital signal approximate a combination of the digital signal and the quantized statistics of the one or more segments.

7. A method as recited in claim 1, wherein the generating comprises embedding a watermark via quantization index modulation (QIM).

8. A computer comprising one or more computer-readable media having computer-executable instructions that, when executed by the computer, perform the method as recited in claim 1.

9. A modulated signal embodied on one or more computer-readable media, the modulated signal being generated in accordance with acts facilitating protection of digital signals, the acts comprising:

partitioning a digital signal into segments;

for one or more segments;

calculating statistics of a segment that are representative of that segment;

quantizing such statistics of a segment;

generating a marked signal equivalent to a combination of the digital signal and the combination of the quantized statistics of the one or more segments.

10. One or more computer-readable media having computer-executable instructions that, when executed by a computer, perform acts facilitating protection of digital signals, the acts comprising:

partitioning a digital signal into segments;

for one or more segments;

calculating statistics of a segment that are representative of that segment;

quantizing such statistics of a segment;

generating a marked signal equivalent to a combination of the digital signal and the combination of the quantized statistics of the one or more segments.

11. A system for facilitating the protection of digital signals, the system comprising:

a partitioner configured to segment a digital signal;

a segment-statistics calculator configured to calculate statistics of a segment that are representative of that segment;

a segment quantizer configured to quantize such statistics of a segment

a signal marker configured to generate a marked signal equivalent to a combination of the digital signal and the combination of the quantized statistics of the one or more segments.