When designing a watermarking algorithm, trade-offs exist among three parameters: payload, fidelity, and robustness. Data payload is the number of bits that can be embedded in the digital data; the fidelity is the degradation introduced into the signal; and the robustness is the ability of the watermark to remain readable after innocent or malicious signal processing operations on the watermarked image. These parameters are conflicting with each other, and they should be set to meet the requirements of the application (Levicky & Foris,2004).
Watermarking techniques are generally classified into spatial domain or the transform domain. The earlier watermarking techniques were almost in the spatial domain. Spatial domain techniques are not resilient enough to image compression and other image processing (Potdar & et al, 2005). Although some methods, e.g. in (Depovere & et al,1998), adopted pre-filtering skill to increase the percentage of identification, experimental results have shown the fundamental disadvantages of spatial domain watermarking. Transform domain watermarking schemes like those based on the discrete cosine transform (DCT) ((Chu, 2003), ( Lin & Chin2000), ( Deng & Wang, 2003)) and the discrete wavelet transform (DWT) ((Hsieh &et al, 2001), ( Reddy & Chatterji, 2005), (Tay & Havlicek, 2002)) typically provide higher image imperceptibility and are much more robust to image manipulations.
It is generally believed that the performance of most existing watermarking systems is not close enough to the fundamental limit on robust watermark embedding rates at which high perceptual image quality is maintained. Although, embedding the watermark in the perceptually significant coefficients could alter the perceived visual quali...
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...f the Third International Conference on Image and Graphics, IEEE, pp. 349 - 352.
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The histogram of an input image is computed for selection of threshold value of a converted gray image. MATLABs ‘imhist(…)’ is the function that is used generate histogram. The appropriate threshold value has been selected, which is, then, applied to an image to threshold itself. Fig 8 and Fig 9 show an example of such images.
describes the Contourlet transform and rotation-scale invariant texture representation. Section 4 contains the description of similarity measure for image retrieval. Simulation results in Section 5 will show the performance of our scheme. Finally,Section 6 concludes this presentation.
Warwick, Kevin. "March of the Machines" The Department of Cybernetics. Internet. Microsoft Internet Explorer. 19 April 1999 Available FTP:http://www.cyber.reading.ac.uk/cybernetics/robots/
This paper discusses three aspects of the field of robotics The first is the history of where the ideas of robotics originated. Second, what was the effect that these ideas had on society? Finally, what developments in the field have proved to be useful to society?
Protecting data through cryptography from unauthorized eyes is a high priority for organizations that store personal information. Cryptography is the process of hiding the real meaning of a message through a pre-determined code that is only known to the person encrypting and decrypting a message. Different forms of cryptography can be seen in our everyday life from the word puzzle in daily newspapers to secretaries writing in short hand. Cryptography has been around since the time of the Egyptians and has made many advances through the years.
The science behind humanlike robots is advancing. They are becoming more smart, mobile and autonom...
Barbara Mowat and Paul Warstine. New York: Washington Press, 1992. Slethaug, Gordon. A. See "Lecture Notes" for ENGL1007.
Nowadays, technology is a dominant feature in the lives of people around the world. Most of daily life activities involve the use of technology which is expanding every day through scientific innovations. However, such innovations do not always occur in every part of the world, but mostly in technologically developed countries, such as South Korea, the USA and Japan. Presently, the development of robotics science has become a subject of considerable attention in those countries. According to Weng, Chen and Sun (2009, 267), “Technocrats from many developed countries, especially Japan and South Korea, are preparing for the human–robot co-existence society that they believe will emerge by 2030.” The word “robot” was introduced in the beginning of 1920th by the Czech playwright Karel Capek from the Czech word “robota”, meaning “forced labor” (Robertson 2007, 373). According to Robertson (2007, 373), robot, in practical usage, can be defined as an autonomous or semiautonomous device that is used to perform its tasks either controlled by human, fractionally controlled and with human guidance or regardless of external actions that are performed by people. Regrettably, the majority of robots in the past centuries could not operate without human control and intervention. However, the progress in robotics over the past few decades enabled humanity to achieve soaring results in creation of autonomous humanoid robots.
Steganography is the art and science of communicating in a way which hides the existence of the communication. In contrast to Cryptography, where the enemy is allowed to detect, intercept, modify messages without being able to violate certain security premises guaranteed by a cryptosystem, the goal of steganographic method is that no one will be able to know whether anything is hidden in the image or not. For hiding secret message in images, there exists a large variety of steganographic techniques some are more complex than others and all of them have respective strong and weak points. Different applications have different requirements of the steganography technique used. Based on the PSNR value of each images, the stego image has a higher PSNR value. The proposed algorithm is based on merge between the idea from the random pixel manipulation methods and Least Significant (LSB) matching of Steganography embedding and extracting method.
Khoshhal K. and M.H.Korayem, Vision based Simulation and Experiment for Performance Tests of Robots.Spinger-Verlag London Limited, 2004,1218-1231. (accessed oct.30,2011)
For thousands of years, cryptography and encryption have been used to secure communication. Military communication has been the leader in the use of cryptography and the advancements. From the start of the internet, there has been a greater need for the use of cryptography. The computer had been invented in the late 1960s but there was not a widespread market for the use of computers really until the late 1980s, where the World Wide Web was invented in 1989. This new method of communication has called for a large need for information security.
Cryptography is the science of hiding information.It converts the meaningful information into some random value and then back to meaningful information. The science of cryptography has been present for past hundreds of years, even long before the invention of computers. Cryptography, over the ages, has been an art practiced by many who have d...
In 2010, robots are very different from the expectations set in 1965. “The latest advances in technology have led to robots that look very much like humans but are mostly able to perform only limited functions.” (Bar-Cohen 12). Yoseph Bar-Cohen and David Hanson’s book ‘The Coming Robot Revolution” is very clear ab...
"Image compression using discrete cosine transform." Georgian Electronic Scientific Journal: Computer Science and Telecommunications 17.3 (2008): 35-43.
Williams, Gray ?Robots and Automation.? The new book of popular science. Grolier Inc., 1996, 186-94.