ECT 582 Internet Security
Digital Watermarking
Security is an integral issue for every industry on the web. Security can be viewed as securing financial information over the Internet to keep prying eyes from stealing sensitive documents. Security can also take the form of securing a server from illegal access or by using digital signatures to prove authenticity and integrity of documents.
This paper will be about securing video, music and graphical information using digital watermarking. Watermarking is not a new technique by any means; however, it is becoming a science that many companies are becoming familiar with due to the high rate of copyright violations. These violations take the form of outright theft by criminals who are out to steal intellectual property, or by unsuspecting violators such as webmasters who do not take the time to investigate the origin of the material they allow on the sites they host.
Doug
Isenberg wrote in an article for Webreference that “Writers, photographers,
musicians, and artists are among those who have taken advantage of the
worldwide publishing opportunities provided by the internet…given the ease with
which audio and visual files can be duplicated, it is no surprise that such
duplication on the Internet regularly occurs without the rightful owners’
permission.” Copyright laws in the U.S.
are designed to protect the intellectual property of those who create art,
graphics, music and any other form of work that is published and can be
copied. Therefore, those who create
intellectual property need a way to protect themselves from lost profits when
they publish on the Web.
Digital
watermarking is quickly becoming the protection needed for publishing music,
digital images and documents. Digital
watermarking is not yet an exact science.
There are a number of companies leading the way with this technology to
protect digital images and other media.
One such company is Signum Technologies (www.signumtech.com). They have developed a number of products
(one called Suresign; another called Veridata) used to embed invisible and
secure identifiers into artists’ works.
The
watermark is used to identify user-defined criteria, the owner of the image and
specific transaction details which can eventually reduce the risk of
counterfeiting images or confirm the integrity of data sent to a client. The watermark is interwoven into the digital
representation of the image and literally becomes a part of the data. The watermark is “virtually impossible to
remove but is so constructed as to minimize any degradation of the image data”
(www.signumtech.com/suresign/index.html). Suresign is used mostly on digital images
and can survive changes in the images such as cropping, rotation and
compression. The detection software
used to read the watermarks can even detect the watermark on images that are
changed by graphic design products or when an image is photocopied, altered and
rescanned.
Veridata
software is used for similar security of records that stand up to judicial or
ethical scrutiny. Veridata software is
used in cases when integrity and authentication issues arise. Veridata uses a checksum process whereby
precisely calculated “patterns” of data are embedded into the records needed to
be secure. The detection software used
to validate the records is able to detect whether records or documents have
been altered in any manner. “Veridata
was developed with security and law-enforcement applications in mind. It goes without saying therefore, that
Veridata is highly secure and incorporates special features to prevent the
validation from being applied or undone by an unauthorised agency” (www.signumtech.com/veridata/index.html).
Another
firm leading the digital watermark and document security frontier is Digimarc (www.digimarc.com). Digimarc has a number patents licensed to
protect multiple forms of media. One
way Digimarc has succeeded in providing copyright protection is by offering
software that embeds watermarks into digital images. The digital images provide a link that lead back to a server that
authenticates image ownership.
Copyrighted material is formatted in such a way that the image or other
product is registered on a server. The
product can be viewed or offered for a limited amount of time to a user, but
the image or software typically cannot be saved or altered without the
creators’ permission (www.digimarc.com/licensing/patent5765152.html).
The
computer industry has not yet come to terms on one standard for digital
watermarking. However, most of the
technology resides around the same concept.
The product to be watermarked is altered in such a way that information
supplied by the company imbedding the watermark is detected. The watermarks are detected by software
downloaded either as a plug-in or as a stand-alone. According to Jian Zhao, writing for BYTE Magazine, “Watermark
extraction includes two main steps: selecting the locations where the watermark
has been inserted…and retrieving the watermark from those locations.” This is a simple definition of the steps and
will only hold true under the condition that what Signum Technologies says
about transforming the images is correct.
If the watermark retains its features regardless of the compression
ratio, cropping or photocopying of the image, then the watermark can be found
intact and be decoded.
The
software being created and implemented by these companies has to gain
acceptance by Internet users and Web masters.
The products being watermarked have no way of being detected if no one
is willing or interested in taking the time to check the authenticity of a
work. Another issue related to user
involvement in the success of digital watermarking is privacy. The same companies that are creating the
watermarks are developing ways to track the watermarks that are being imbedded
into the property they mean to protect.
The
proposed way of detecting these watermarks is to have a sort of “watermark
police” that search on the Web for tampered with images or video or audio
files. Peter F. Cassidy writes, “If
watermarking content develops into a universally addressable format, then we
very well may reach a threshold at which digital ‘copyright cops’ could begin
to ride the web checking up on everyone’s rights to publish”. This means that software could be written to
seek out watermarks on personal, private or public Websites and servers. This would have huge ramifications on where
the Federal Government goes with Internet privacy for its users.
In
all, digital watermarking is a good way to protect creators of intellectual
property from having their ideas stolen off of the Web. The intent by some companies creating this
software for added security of this property is for the good of the creators
and users. However, we need to keep in
mind that with technology needing to be tracked in order to verify authenticity
or proof of originality comes a possible invasion of privacy.
Cassidy,
Peter F. www.netscapeworld.com/nw-03-1997/nw-03-watermark.html
Isenberg,
Doug. www.webreference.com/content/watermarks/index.html
www.signumtech.com/suresign/index.htm
www.signumtech.com/veridata/index.htm
Zhao,
Jian. www.byte.com/art/9701/sec18/art1.htm