Abstract: This paper presents a high secure data hiding technique using image cropping and Least Significant Bit (LSB) steganography. The predefined certain secret coordinate crops will be extracted from the cover image. The secret text message will be divided into sections. These sections quantity is equal the image crops quantity. Each section from the secret text message will embed into an image crop with a secret sequence using LSB technique. The embedding is done using the cover image color channels. Stego image is given by reassembling the image and the stego crops. The results of the technique will be compared to the other state of art techniques. Evaluation is based on visualization to detect any degradation of stego image, the difficulty of extracting the embedded data by any unauthorized viewer, Peak Signal-to-Noise Ratio of stego image (PSNR), and the embedding algorithm CPU time. Experimental results ensure that the proposed technique is more secure compared with the other traditional techniques.
Abstract: Image steganography is the best aspect of information hiding. In this, the information is hidden within an image and the image travels openly on the Internet. The Least Significant Bit (LSB) is one of the most popular methods of image steganography. In this method, the information bit is hidden at the LSB of the image pixel. In one bit LSB steganography method, the total numbers of the pixels and the total number of message bits are equal to each other. In this paper, the LSB method of image steganography is used for watermarking. The watermarking is an application of the steganography. The watermark contains 80*88 pixels and each pixel requirs 8 bits for its binary equivalent form so, the total number of bits required to hide the watermark are 80*88*8(56320). The experiment was performed on standard 256*256 and 512*512 size images. After the watermark insertion, histogram analysis was performed. A noise factor (salt and pepper) of 0.02 was added to the stego image in order to evaluate the robustness of the method. The watermark was successfully retrieved after insertion of noise. An experiment was performed in order to know the imperceptibility of stego and the retrieved watermark. It is clear that the LSB watermarking scheme is robust to the salt and pepper noise.
Abstract: Computer technology and the Internet have made a
breakthrough in the existence of data communication. This has
opened a whole new way of implementing steganography to ensure
secure data transfer. Steganography is the fine art of hiding the
information. Hiding the message in the carrier file enables the
deniability of the existence of any message at all. This paper designs
a stego machine to develop a steganographic application to hide data
containing text in a computer video file and to retrieve the hidden
information. This can be designed by embedding text file in a video
file in such away that the video does not loose its functionality using
Least Significant Bit (LSB) modification method. This method
applies imperceptible modifications. This proposed method strives
for high security to an eavesdropper-s inability to detect hidden
information.
Abstract: A high performance computer includes a fast
processor and millions bytes of memory. During the data processing,
huge amount of information are shuffled between the memory and
processor. Because of its small size and its effectiveness speed, cache
has become a common feature of high performance computers.
Enhancing cache performance proved to be essential in the speed up
of cache-based computers. Most enhancement approaches can be
classified as either software based or hardware controlled. The
performance of the cache is quantified in terms of hit ratio or miss
ratio. In this paper, we are optimizing the cache performance based
on enhancing the cache hit ratio. The optimum cache performance is
obtained by focusing on the cache hardware modification in the way
to make a quick rejection to the missed line's tags from the hit-or
miss comparison stage, and thus a low hit time for the wanted line in
the cache is achieved. In the proposed technique which we called
Even- Odd Tabulation (EOT), the cache lines come from the main
memory into cache are classified in two types; even line's tags and
odd line's tags depending on their Least Significant Bit (LSB). This
division is exploited by EOT technique to reject the miss match line's
tags in very low time compared to the time spent by the main
comparator in the cache, giving an optimum hitting time for the
wanted cache line. The high performance of EOT technique against
the familiar mapping technique FAM is shown in the simulated
results.
Abstract: Distributed Computing Systems are usually considered the most suitable model for practical solutions of many parallel algorithms. In this paper an enhanced distributed system is presented to improve the time complexity of Binary Indexed Trees (BIT). The proposed system uses multi-uniform processors with identical architectures and a specially designed distributed memory system. The analysis of this system has shown that it has reduced the time complexity of the read query to O(Log(Log(N))), and the update query to constant complexity, while the naive solution has a time complexity of O(Log(N)) for both queries. The system was implemented and simulated using VHDL and Verilog Hardware Description Languages, with xilinx ISE 10.1, as the development environment and ModelSim 6.1c, similarly as the simulation tool. The simulation has shown that the overhead resulting by the wiring and communication between the system fragments could be fairly neglected, which makes it applicable to practically reach the maximum speed up offered by the proposed model.
Abstract: Least Significant Bit (LSB) technique is the earliest
developed technique in watermarking and it is also the most simple,
direct and common technique. It essentially involves embedding the
watermark by replacing the least significant bit of the image data with
a bit of the watermark data. The disadvantage of LSB is that it is not
robust against attacks. In this study intermediate significant bit (ISB)
has been used in order to improve the robustness of the watermarking
system. The aim of this model is to replace the watermarked image
pixels by new pixels that can protect the watermark data against
attacks and at the same time keeping the new pixels very close to the
original pixels in order to protect the quality of watermarked image.
The technique is based on testing the value of the watermark pixel
according to the range of each bit-plane.