Non-stationary signal processing applications use standard nonredundant DWT (Discrete Wavelet Transform) which is very powerful tool. But it suffers from shift sensitivity, absence of phase information, and poor directionality. To remove out these limitations, many researchers developed extensions to the standard DWT such as WP (Wavelet Packet Transform), and SWT (Stationary Wavelet Transform)....

With the help of various image editing tools available, it has become easier to alter an image in such a way that it does not leave behind any clues. Copy –Move forgery or also known as Region Duplication Forgery is a type of image forgery in which a part of digital image is copied and pasted to another part of same image. Since the copied and pasted image comes from the same image, it becomes ...

Most of a signal information is often carried by irregular structures and transient phenomena. The mathematical characterization of singularities with Lipschitz exponents is explained. Theorems are reviewed that estimate local Lipschitz exponents of functions from the evolution across scales of their wavelet transform. It is then proven that the local maxima of the wavelet transform modulus det...

—ASIC hardware implementations of the discrete wavelet transform are required to cope with the intensive real-time computations of the transform. In this paper, we describe a parallel implementation of the wavelet transform using one type of reconfigurable ASICs; Filed Programmable Gate Arrays (FPGAs). The implementation is based on reformulating the transform using the distributed arithmetic a...

An image watermarking scheme based on singular value decomposition and visual cryptography in discrete wavelet transform is proposed. We start with a survey of the current image watermarking technologies, and have noticed that majority of the existing schemes are not capable of resisting all attacks. We propose the idea to use of singular value decomposition and visual cryptography in discrete ...

Abstrac t This paper presents a method for locating and measuring the size of cracks in beams by time of flight (ToF) of ultrasonic wave. The echo detected was processed using the stationary wavelet transform and the Hilbert transform. The accuracy of the information obtained from the processed signal depends on the selected mother wavelet. To select the best mother wavelet for signal processin...

The following paper introduces a low bitrate video coding method on the basis of 3D motion compensated wavelet transform and SPIHT algorithm. In contrast to the conventional algorithms applying motion compensation and differential coding, here wavelet transform is used to exploit the opportunities of time redundancy. For coefficient collection, the 3D version of SPIHT algorithm was selected fro...

The computation complexity dominates Continuous Wavelet Transform (CWT) and the low frequency resolution limit the Discrete Wavelet Transform (DWT). The degradation in frequency resolution in Discrete Wavelet Transform (DWT) is due to the fact, that, DWT decomposes only the approximation coefficients at each level. This detail is not enough to analyse the signal like knock in the engine. The ac...

In this paper, we develop the theory of the wavelet transform over Galois elds. To avoid the limitations inherent in the number theoretic Fourier transform over nite elds, our wavelet transform relies on a basis decomposition in the time domain rather than in the frequency domain. First, we characterize the in nite dimensional vector spaces for which an orthonormal basis expansion of any sequen...

This paper proposes a novel progressive image compression algorithm using the nonlinear contourlet transform. Contourlets are effective in capturing directional information in images using a flexible set of basis functions that are elongated and directional. Since the contourlet transform is redundant, a wavelet based contourlet transform has been applied on the image. The wavelet based contour...