Featured Research

from universities, journals, and other organizations

Reversible watermarking for digital images

Date:
July 7, 2010
Source:
Inderscience Publishers
Summary:
Every picture tells a story, but how do you know that a digital photo has not been manipulated to change the tale being told? A new approach to adding an encrypted watermark to digital images allows the an image to be validated against a pass key, according to new research.

Every picture tells a story, but how do you know that a digital photo has not been manipulated to change the tale being told? A new approach to adding an encrypted watermark to digital images allows the an image to be validated against a pass key, according to research published in the International Journal of Signal and Imaging Systems Engineering.

Visible watermarks are routinely added to digital images as a form of copy protection, but their presence essentially destroys the picture, obliterating information within altered pixels in a way that cannot be reversed. Now, Dakshinamurthi Sivakumar and Govindarajan Yamuna of Annamalai University, in Tamil Nadu, India, have developed a new, reversible watermarking scheme. The system could be used initially for the authentication of military images.

Inexpensive image editing software is now available that can be used to make essentially undetectable "photo realistic" changes to almost any photograph, the team explains. In a military setting it is important to prevent unauthorized manipulation of digital images and to be able to demonstrate credibility and provenance.

"Traditionally, source authentication and integrity verification of digital data have been carried out with digital signatures and encrypted watermarks," the team says, "Unfortunately, watermarking techniques modify original data as a modulation of the watermark information and unavoidably cause permanent distortion to the original data." Reversible, or lossless, watermarking is therefore required for many highly sensitive applications.

The team has now developed a reversible watermarking system based on calculating the parameters of every pixel in the image but nevertheless at low computer power. This information is converted into a code, a Hash Message Authentication Code (HMAC), of the image where distinct pixel values are selected for embedding watermark bits and the preferred pixel values are stored as a key. The key thus generated is used for both the watermark extraction and restoration of the original image. The extracted HMAC and the HMAC of the restored image can be compared to verify that the received image is authentic and has not been altered.


Story Source:

The above story is based on materials provided by Inderscience Publishers. Note: Materials may be edited for content and length.


Cite This Page:

Inderscience Publishers. "Reversible watermarking for digital images." ScienceDaily. ScienceDaily, 7 July 2010. <www.sciencedaily.com/releases/2010/07/100706112605.htm>.
Inderscience Publishers. (2010, July 7). Reversible watermarking for digital images. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2010/07/100706112605.htm
Inderscience Publishers. "Reversible watermarking for digital images." ScienceDaily. www.sciencedaily.com/releases/2010/07/100706112605.htm (accessed July 29, 2014).

Share This




More Computers & Math News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

It's Not Just Facebook: OKCupid Experiments With Users Too

It's Not Just Facebook: OKCupid Experiments With Users Too

Newsy (July 29, 2014) If you've been looking for love online, there's a chance somebody has been looking at how you're looking. Video provided by Newsy
Powered by NewsLook.com
Why Facebook Wants You To Download Its Messenger App

Why Facebook Wants You To Download Its Messenger App

Newsy (July 29, 2014) Facebook will start requiring users to download a separate Messenger application if they wish to continue using Facebook for mobile messaging. Video provided by Newsy
Powered by NewsLook.com
Teen's Phone Ignites Under Her Pillow; How Real Is The Risk?

Teen's Phone Ignites Under Her Pillow; How Real Is The Risk?

Newsy (July 28, 2014) A Texas teen's Samsung phone apparently ignited while she slept, but what was the real problem here? Video provided by Newsy
Powered by NewsLook.com
Zillow Snaps Up Web Real Estate With Trulia Deal

Zillow Snaps Up Web Real Estate With Trulia Deal

Reuters - US Online Video (July 28, 2014) Zillow's decision to buy rival Trulia is just one step in a continuing string of acquisitions, and Zillow CEO Spencer Rascoff is already thinking about his next big deal. Bobbi Rebell reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins