Speech Steganography System Using Lifting Wavelet Transform

This paper presents a new lossless speech steganography approach based on Integer-to-Integer Lifting Wavelet Transform (Int2Int LWT) and Least Significant Bits (LSBs) substitution. In order to increase the security level a simple encryption with chaotic key has been proposed. The proposed system has a high sensitivity in choosing keys because a small change in CKG causes a new secret key for transmitting. Speech steganography algorithm that based on (Int2IntLWT) can satisfy full recovery for the embedded secret messages in the receiver side. Keywords:Speech steganography, information hiding, Int2Int LWT, (LSB) technique, XOR operation

Design of DWT Module

Abstract Due to the advancements in information and communication technologies, the electronic transfer of formal documents such as business deals, etc is inevitable. Therefore a DWT based authentication method is proposed in this paper. The formal text document is watermarked by embedding the fingerprint image of the authenticated personnel. DWT is being widely considered in watermarking applications because of its efficient multi-resolution in frequency domain. The lifting based 2D-DWT with two levels of computation is implemented. The 2D-DWT can be implemented by performing 1D DWT row-wise and column wise. Hence with the help of DWT filters both document and the fingerprint image are compressed and it's divided into sub-bands and the fingerprint is watermarked in the document. The complete system is implemented on FPGA

Accelerating FPGA-based evolution of wavelet transform filters by optimized task scheduling

Adaptive embedded systems are required in various applications. This work addresses these needs in the area of adaptive image compression in FPGA devices. A simplified version of an evolution strategy is utilized to optimize wavelet filters of a Discrete Wavelet Transform algorithm. We propose an adaptive image compression system in FPGA where optimized memory architecture, parallel processing and optimized task scheduling allow reducing the time of evolution. The proposed solution has been extensively evaluated in terms of the quality of compression as well as the processing time. The proposed architecture reduces the time of evolution by 44% compared to our previous reports while maintaining the quality of compression unchanged with respect to existing implementations. The system is able to find an optimized set of wavelet filters in less than 2 min whenever the input type of data changes

Discrete wavelet transform realisation using run-time reconfiguration of field programmable gate array (FPGA)s

Abstract: Designing a universal embedded hardware architecture for discrete wavelet transform is a challenging problem because of the diversity among wavelet kernel filters. In this work, the authors present three different hardware architectures for implementing multiple wavelet kernels. The first scheme utilises fixed, parallel hardware for all the required wavelet kernels, whereas the second scheme employs a processing element (PE)-based datapath that can be configured for multiple wavelet filters during run-time. The third scheme makes use of partial run-time configuration of FPGA units for dynamically programming any desired wavelet filter. As a case study, the authors present FPGA synthesis results for simultaneous implementation of six different wavelets for the proposed methods. Performance analysis and comparison of area, timing and power results are presented for the Virtex-II Pro FPGA implementations

FPGA implementation of moving object and face detection using adaptive threshold

The real time moving object and face detections are used for various security applications. In this paper, we propose FPGA implementation of moving object and face detection with adaptive threshold. The input images are passed through Gaussian filter. The 2D-DWT is applied on Gaussian filter output and considered only LL band for further processing to detect object/face. The modified background subtraction technique is applied on LL bands of input images. The adaptive threshold is computed using LL-band of reference image and object is detected through modified background subtraction. The detected object is passed through Gaussian filter to get final good quality object. The face detection is also identified using matching unit along with object detection unit. The reference image is replaced by face database images in the face detection. It is observed that the performance parameters such as TSR, FRR, FAR and hardware related results are improved compared to existing techniques

FPGA IMPLEMENTATION OF MOVING OBJECT AND FACE DETECTION USING ADAPTIVE THRESHOLD

The real time moving object and face detections are used for various security applications. In this paper, we propose FPGA implementation of moving object and face detection with adaptive threshold. The input images are passed through Gaussian filter. The 2D-DWT is applied on Gaussian filter output and considered only LL band for further processing to detect object/face. The modified background subtraction technique is applied on LL bands of input images. The adaptive threshold is computed using LL-band of reference image and object is detected through modified background subtraction. The detected object is passed through Gaussian filter to get final good quality object. The face detection is also identified using matching unit along with object detection unit. The reference image is replaced by face database images in the face detection. It is observed that the performance parameters such as TSR, FRR, FAR and hardware related results are improved compared to existing techniques

Implementation of fingerprint based biometric system using optimized 5/3 DWT architecture and modified CORDIC based FFT

The real-time biometric systems are used to authenticate persons for wide range of security applications. In this paper, we propose implementation of fingerprint-based biometric system using Optimized 5/3 DWT architecture and Modified CORDIC-based Fast Fourier Transform (FFT). The Optimized 2D-DWT architecture is designed using Optimized 1D-DWT architectures, Memory Units and novel Controller Unit which is used to scan rows and columns of an image. The database fingerprint image is applied to the proposed Optimized 2D-DWT architecture to obtain four sub-bands of LL, LH, HL and HH. The efficient architecture of FFT is designed by using Modified CORDIC processor which generates twiddle factor angles of range – using Pre-processing Unit and Comparator Block. Further, the LL sub-band coefficients are applied to the Modified CORDIC based FFT to generate final fingerprint

Privacy-Enhancing Methods for Time Series and their Impact on Electronic Markets

The amount of collected time series data containing personal information has increased in the last years, e.g., smart meters store time series of power consumption data. Using such data for the benefit of society requires methods to protect the privacy of individuals. Those methods need to modify the data. In this thesis, we contribute a provable privacy method for time series and introduce an application specific measure in the smart grid domain to evaluate their impact on data quality