Digitalwatermarking

By:-jaykrishna ThakkarFy Msc-it

wHat iS a watermark..? Watermarking is an important

mechanism applied to physical objects like bills, papers, garment labels ,product packing…

Physical objects can be watermarked using special dyes and inks or during paper

manufacturing.

CHaraCteriStiCS of watermarkS

The watermark is hidden from view during normal use, only become visible by adopting a special viewing process.

– E.g. hold the bill up to light The watermark carries information

about the object in which it is hidden. – E.g. the authenticity of the bill – E.g. the trademark of the paper

manufacturer

HiStory of watermarking

The term “watermark” was probably originated from the German term “wassermarke”. Since watermark is of no importance in the creation of the mark, the name is probably given because the marks resemble the effects of water on paper.

Papers are invented in China over a thousand years ago. However, the first paper watermark did not appear until 1282, in Italy.

HiStory of watermarking

By the 18th century, watermarks on paper in Europe and America had been used as trademarks, to record the manufactured date, or to indicate the size of original sheets.

Watermarks are commonly used on bills nowadays to avoid counterfeiting

wHat iS Digital watermarking?

Watermarking can also be applied to digital signals!

image video Audio

HiStory of Digital watermarking

The first watermarking example similar to the digital methods nowadays appeared in 1954.

The Muzak Corporation filed a patent for “watermarking” musical Work. An identification Work was inserted in music by intermittently applying a narrow notch filter centred at 1KHz.

About 1995, interest in digital watermarkingbegan to mushroom.

Definitions about Digital watermarking

Digital watermarking:– The practice of imperceptibly alternating a Work to embed a message about the Work.

– Related terms Work: a specific copy of some electronic signal, such as a song, a video sequence, or a picture Cover Work: the original un-watermarked work,

since it covers (hides) the watermark Watermark: the messages being embedded, indicating some information about the work

How it works…

types of watermark

Visible A visible translucent

image which is overlaid on the primary image

Invisible An overlaid image

which cannot be seen, but which can be detected algorithmically

Visible watermark

Logo or seal of the organization which holds the rights to the primary image, it allows the primary image to be viewed, but still marks it clearly as the property of the owning organization.

Overlay the watermark in a way which makes it difficult to remove, if the goal of indicating property rights is to be achieved.

Visible watermark

inVisible watermark

Embedding level is too small to notice Can be retrieved by extraction software Applications:

AuthenticationCopyrightingEtc…

inVisible watermark

ApplicAtions of digitAl wAtermArking

Rights management

Contents management

Access/copy control

Authentication

feAtures of wAtermArking

Invisible/Inaudible Information is embedded without digital content

degradation, because of the level of embedding operation is too small for human to notice the change.

Inseparable The embedded information can survive after some

processing, compression and format transformation. Unchanging data file size

Data size of the media is not changed before and after embedding operation because information is embedded directly into the media.

technicAl requirements for wAtermArking

Invisibility

Robustness Capacity

digitAl wAtermArking AlliAnce

Represents applications and solutions for:

Audio and Music Content

Video, Movies and TV Content

Digital Imagery

Identity Documents

Value Documents

digitAl wAtermArking AlliAnce members

digitAl wAtermArking exAmples

Copyright Communication Copy Protection

Monitoring Filtering/Classification Authentication/Integrity

Product Serialization & Tracking Asset/Content Management Rights Management Remote Triggering Linking/E-Commerce

copyright digitAl wAtermArk Architecture

Audio/Video MasterEmbed Copyrightand Content ID DWM

Content Owner

Provider Index Database Location(Centralized or Distributed)

User’s PC

Rip SoftwareCompressed Audio/VideoFile (e.g. MP3 file)

User SoftwareDetect Copyright and Content ID DWM for Secure and Enhanced content

Rights & Info Database

Content ID linked to rights, information

and related content

Can be used to address P2P and social network content Identification needs as well

as providing identification of orphan works and access to metadata/networked

information

Digital MeDia Serialization & tracking

Identifies content owners and rights while communicating copyright information

Awareness of watermarked content by consumer creates deterrent against unauthorized copying and distribution

Provides accurate identification of source of unauthorized content discovered on the Internet and/or physical media

Protected for privacy

Recordable Media

EmbedSerial # (2)

EmbedSerial # (1)

Content ID

Retail Content

Content Provider

Track and take proper action Detect

Serial Number

any queStionS…