Madhu Shandilya

Random-valued impulse noise removal using adaptive dual threshold median filter

Adaptive dual threshold based noise detection.Averaging based dual threshold computation.Simple median filter based noise removal.Improved de-noised image quality in terms of PSNR. Noise detection and its removal is very important in the image processing. Detection of noise is very crucial and significant in random valued impulse noise because it does not hamper the image pixels uniformly. This paper presents a novel and unique concept of adaptive dual threshold for the detection of random valued impulse noise along with simple median filter at noise removal stage. Simulation results shows that an efficient noise detection leads to a superior quality of de-noised image as compared to existing adaptive threshold based image de-noising techniques. Proposed threshold computation is based on averaging of pixel values of window which enhances the PSNR of our system as compared to existing median filter based image de-noising methods.

A Compact UWB Microstrip Antenna with Modified Ground Plane for Bandwidth Enhancement

This paper presents a bandwidth enhancing technique using a modified ground plane with diagonal edges, L-shaped slot and parasitic patches with main patch for the design of compact antennas. The proposed low-cost, compact-size rectangular patch antenna on 4.7 cm × 3.6 cm printed circuit board (FR-4) is designed and validated through simulations and experiments. Results show that the ground plane with Lshaped slot in presence of the diagonal cuts at the top corners and the rectangular parasitic patches can increase the bandwidth. Return losses of −23.6 dB and −29.7 dB for the first and second resonant frequencies, respectively, can be achieved when the depth of the diagonal cut is 3 mm, the dimension of each rectangular parasitic patch is 10 mm×3.5 mm, and the L-shaped slot size is 7.5 mm ×2.5mm, providing a 41.27% wider bandwidth than Federal Communication Commission’s(FCC) standard. General Terms Designing of Microstrip Antenna.

Image de-noising by dual threshold median filtering for random valued impulse noise

In the field of digital image processing[4], noise removal is always a critical process. In this paper we proposed an enhanced method of image de-noising. The purpose of this new method is to improve the signal to noise ratio (SNR) of de-noised image and get more better image, especially when image corrupted by high noise density. We improved the median filter algorithm, and get comparatively better results than previous methods. The mathematical analysis shows that this process improve the PSNR[8] (Peak signal to noise ratio) at high density noise level. This method used the combination of median and average functions. Two levels of threshold and improved median value remove the noise much effectively. The mathematical analysis shows that the analysis of the noisy pixels and use of noise-free pixels for de-noising purpose produces much better results and gives better quality de-noised version.

Image Encryption using Block Shuffling and Affine Transform: A Review

The rapid development of communication technology due to the global spread of the internet and the digital information revolution has given rise to a huge increase in the use and transmission of multimedia information. Encryption technology is studied in this paper, and a new image encryption algorithm based on correlation of pixels is proposed. The main goal of this paper is security management. Researchers have proposed incompatible methods to encrypt images. So, here we go through a new way of image encryption and decryption using block based image encryption using affine transform. First of all the plain image is divided into fixed size blocks. All these blocks then shuffled according to the proposed algorithm and we get a block shuffled image. At last the encrypted algorithm of affine is used iteratively for each of the pixels. It uses the keys for the purpose of encryption.

Imprecise reversible visible watermarking

Using the program visible digital, a perceptible watermark is added to an image to prevent illicit use of multimedia content and to provide copyright and copy protection for the author. There are numerous applications that require user authentication to make the original image content available. If the original image is recovered from the watermarked image successfully, then the scheme is said to be a reversible watermarking scheme. However, most of the reversible visible watermarking schemes found in the current literature do not preserve visual quality of image. In this investigation, we propose a novel reversible and visible watermarking method that is suitable for both grey and colour images. In our approach, we use the complex mapping of pixels via embedding combined with a scaling factor derived from the contrast-sensitive function of the original image. We then prove experimentally that our scheme is advantageous over the previous works in this field. Furthermore, we compare the performance of proposed work with other state-of-the-art under various parameters.

Attacks resistant hybrid watermarking scheme

The main objective of developing an image-watermarking technique is to satisfy both imperceptibility and robustness requirements. To attain this objective, a hybrid image-watermarking scheme based on Discrete wavelet transform (DWT) and Singular value decomposition (SVD) is proposed in this paper. In order to improve the robustness and imperceptibleness of the watermarked image, a new embedding and extracting method with DWT-SVD is proposed. The LH Band of the third level of image in DWT domain is modified with SVD to embed the singular value of watermark to the singular value of DWT coefficient. The proposed embedding and extracting methodology was employed to accelerate the hybrid DWT-SVD watermarking and to avoid the leak of watermark. This hybrid technique results to optimize both (robustness and imperceptibility) the fundamentally conflicting requirements. The experimental result shows the good robustness under numerous attacks and the high fidelity. The time required to perform the program is greatly decreased.

PSO OPTIMIZED WIDEBAND LPDA ANTENNA WITH NON-CROSS FEED STRUCTURE

An optimized design of Log Periodic Dipole Array (LPDA) antenna with non-cross feed structure is reported in this paper. Particle Swarm Optimization (PSO) is utilized to reduce the size and enhance the bandwidth of proposed antenna. Proposed design employs an improved feed structure of non-cross feed array antenna to avoid complexity of conventional feeding with long coaxial line and creating Co Planar Waveguide (CPW) feed. A simple FR-4 substrate with thickness of 1 mm is utilized for simulation using CST. A fitness function based on S11 parameter is used to achieve the optimization goal. A prototype of proposed PSO optimized antenna is developed to validate the simulation results. The proposed antenna offers higher bandwidth and significantly smaller size than cross feed LPDA antennas, with less complexity and low cost through parameter optimization, while maintaining the log periodic nature and gain.

A compact wideband microstrip patch antenna with defected ground plane

In this paper, a compact design and construction of microstrip broadband antenna is proposed. The proposed antenna has the capability of operating between 1.8GHz to 12GHz. The antenna parameter in frequency domain analysis has been investigated to show its capability as an effective radiating element. The simulation results demonstrated good broadband linear transmission performance. A prototype is developed and measurement results are well in agreement. The highest efficiency claimed 92% at 2 GHz and minimum efficiency is 70%. The measured E-plane and H-plane radiation pattern in the entire bandwidth are identical in shape and the direction of maximum radiation is normal to the patch geometry. The designed antenna has a modified ground plane with diagonal edges, L-shaped slot and parasitic patches to main patch for the design of comp act antennas. The proposed low-cost, compact-size rectangular patch antenna on 4.7cm × 3.6cm printed circuit board (FR-4) is designed.

An Image Encryption using Block based Transformation and Bit Rotation Technique

Along with the rapid increasing growth of computer and network technologies, images are being transmitted more and more frequently. Security of image is a big issue. Image information is lively and visual, and has been an important means of expressing information of person. There are many encryption algorithm had been available each one having some strength and weakness. In this paper we present an image encryption technique that combines the concept of block based transformation and pixel manipulation. The proposed method consist of two stages 1) In first step we apply block based matrix transformation for pixel position manipulation; 2) In second stage, apply bit rotation technique that change the value of each pixel.

Analysis of Mesh Topology of NoC for Blocking and Non-blocking Techniques

Network on Chip is efficient on-chip communication architecture for system on chip architectures. It enables the integration of a large number of computational and storage blocks on a single chip. The router is the basic element of NoC. The router architecture can be used for building a NoC with standard topology with low latency and high speed. In this paper, we implement and analyze a 3x3 mesh network configuration with routers which can support simultaneous routing requests, with blocking and non blocking inputs.