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Digital Watermarking. Thái Chí Minh Trần Lương Khiêm. Content. Introduction History Applications Requirements Techniques Attacks. Content. Introduction History Applications Requirements Techniques Attacks. Introduction. 499.99 = 0.99. Introduction. Introduction.

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Digital Watermarking

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Digital watermarking

Digital

Watermarking

Thái Chí Minh

Trần Lương Khiêm


Content

Content

  • Introduction

  • History

  • Applications

  • Requirements

  • Techniques

  • Attacks


Content1

Content

  • Introduction

  • History

  • Applications

  • Requirements

  • Techniques

  • Attacks


Introduction

Introduction

499.99 = 0.99


Introduction1

Introduction


Introduction2

Introduction

Digital watermarking

Steganography


Introduction3

Introduction

Digital watermarking

Relation between embedded message and cover work

Goal and assumption

Steganography


Content2

Content

  • Introduction

  • History

  • Applications

  • Requirements

  • Techniques

  • Attacks


History

History

Fabriano

Histiæus & the slave

Paper watermark, 1282

Banknote. 18th century


History1

History

  • In 1954, Emil Hembrooke of the Muzak Corporation filed a patent for watermarking” musical Works

  • The first Information Hiding Workshop (IHW) ,which included digital watermarking as one of its primary topics, was held in 1996


Content3

Content

  • Introduction

  • History

  • Applications

  • Requirements

  • Techniques

  • Attacks


Applications

Applications

  • Broadcast monitoring

  • Owner identification

  • Proof of ownership

  • Transaction tracking

  • Content authentication

  • Copy control


Broadcast monitoring

Broadcast monitoring

Advertisement

Rebroadcasting


Owner identification

Owner identification

Original

Lena Soderberg, 1972


Proof of ownership

Proof of ownership

Bob

Alice


Transaction tracking

Transaction tracking


Transaction tracking1

Transaction tracking


Content authentication

Content authentication

  • Digital signature is NOT enough


Content authentication1

Content authentication


Copy control

Copy control

  • Cryptography is NOT enough


Copy control1

Copy control


Content4

Content

  • Introduction

  • History

  • Applications

  • Requirements

  • Techniques

  • Attacks


Requirements

Requirements

  • Perceptual Transparency

  • Robustness

  • Data payload

  • With / Without originals

  • Security


Perceptual transparency

Perceptual Transparency


Robustness

Robustness

  • Fragile

  • Semi-fragile

  • Robust


Data payload

Data payload

  • Data payload refers to the number of bits a watermark encodes within a unit of time or within a Work

  • Different applications may require very different data payloads


With without originals

With / Without originals

  • Non-blind watermarking

    • Type I

    • Type II

  • Semi-blind watermarking

  • Blind watermarking


Security

Security

(Present later)


The mutual dependencies among the elements

The mutual dependencies among the elements


Content5

Content

  • Introduction

  • History

  • Applications

  • Requirements

  • Techniques

  • Attacks


Techniques

Techniques

  • LSB

  • Spread spectrum

  • Applying on Vietnamese documents


Techniques1

Techniques


Techniques2

Techniques

  • There are many techniques to do watermarking in digital things:

    • Spatial domain watermarking: LSB, in text data, …

    • Transform domain watermarking: frequency-based watermarking, wavelet based watermarking

      • Embedding the watermark in the transform domain from carrier object (using DCT, DFT, DWT, …)


Techniques3

Techniques

  • LSB:

    • Embedding:

      • Choosing some representation values (e.g pixels) of carrier object.

      • Embed the bits of message (watermark) to LSBs of representation value

        • Message ‘A’: 100 0001

        • Carrier object: RGB (2 bits)

          100000 010101 101100

          010001 100001 000100

          101110 011010 111000


Techniques4

Techniques

  • LSB:

    • Embedding:

      • Choosing some representation values (e.g pixels) of carrier object.

      • Embed the bits of message (watermark) to LSBs of representation value

        • Message ‘A’: 100 0001

        • Carrier object: RGB (2 bits)

          100001 010100 101100

          010000 100001 000100

          101111 011010 111000


Techniques5

Techniques

  • LSB:

    • Detector:

      • Retrieve the watermark by having the knowledge of the representation values (e.g pixels) used for embedding individuals bits


Techniques6

Techniques

  • Spread spectrum

    • Using frequency domain transform to convert the input image into another domain and embedding the watermark to this domain.


Techniques7

Techniques

  • Apply on Vietnamese documents


Techniques8

Techniques

  • Apply on Vietnamese documents


Techniques9

Techniques

  • Apply on Vietnamese documents

    • Besides, we can use some methods:

      • Vertically shifting text lines

      • Horrizontally shifting words


Content6

Content

  • Introduction

  • History

  • Applications

  • Requirements

  • Techniques

  • Attacks


Attacks

Attacks

  • From processing

  • From attackers


Attacks1

Attacks

  • The actions take effect on the watermark embedded in carrier objects.

    • Affects:

      • Destroying the watermark or modifying the watermark with new wrong information.

      • Removing the watermark entirely.

    • But: not degrading the quality of carrier objects (image, audio, video)

    • Relating to a requirements of watermarking: Robustness


Attacks2

Attacks

  • Classification:

    • From proscessing carrier objects

      • Common signal processing: digital-to-analog and analog-to-digital conversion, or change image contrast, color, JPEG compression, …

      • Common geometric distortions: scaling, rotating, cropping, dithering …

    • From attacker

      • Mosaic

      • Collusion attacks: get the watermark or remove watermarks entirely to get the original work.


Attacks3

Attacks


Attacks4

Attacks

Mosaic attack


Attacks5

Attacks

  • How to protect watermarks from attacks

    • Understanding and applying new researchs in watermarking

    • Using StirMarkBenchmark evaluation engine to evaluate your watermarking scheme

      • “All vendors of digital watermarks have their products benchmarked by Stirmark and as of August 2001, no watermark from any vendor survives the test, ie: the watermarks are all removed without degradation to image quality occurring. “


Digital watermarking

Questions & Answers

Thank you


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