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ASeminar
On
Watermarking
ContentsIntroductionHistoryTypes of watermarkAttributes associated with watermarking Techniques ApplicationsAdvantagesDisadvantagesConclusionReferences
IntroductionDigital Watermarking describes methods
and technologies that hide information, for example a number or text, in digital media, such as images, video.
Watermarking is the insertion of imperceptible and inseparable information into data for data integrity.
General Watermarking
Procedure
History More than 700 years ago, watermarks were used
in Italy to indicate the paper brand and the mill that produced it.
By the 18th century watermarks began to be used as Anticounterfeiting measures on money and other documents. The term watermark was introduced near the end of the 18th century.
The first example of a technology similar to digital watermarking is a patent filed in 1954 by Emil Hem Brooke .
In 1988, Komatsu and Tominaga appear to be the first to use the term “digital watermarking”.
Digital Watermark
Digital watermark is a message which is embedded into digital content that can be extracted or detected later.
Types of Watermark
VisibleInvisiblePublicFragile
Attributes Associated With Watermarking
Imperceptibility Robustness Security Complexity Verification
Watermarking Techniques• Watermarking for text
Word space coding Line shift coding
Watermarking Techniques……..• Watermarking for text
Feature coding
Watermarking Techniques……• watermarking for images
spatial domain watermarkingFrequency domain watermarking
Detection of watermarks
Applications• Copy prevention or control
• In the field of data security
Applications………• Tampering with images