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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
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.
inVisible watermark
Embedding level is too small to notice Can be retrieved by extraction software Applications:
AuthenticationCopyrightingEtc…
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.
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