In this paper, image compression using orthogonal wavelet transforms of Walsh, Cosine, Haar, Kekre, Slant and Sine is studied. Wavelet transform of size N 2 xN 2 is generated using its corresponding orthogonal transform of size NxN. These wavelet transforms are applied on R, G, and B planes of 256x256x3 size colour images separately. In each transformed plane rows/columns are sorted in their de...

Many transform based image compression methods have been experimented till now. This paper proposes novel image compression method using hybrid slant transform. Slant transform is used as base transform to focus on global features of an image. Sinusoidal orthogonal transforms like DCT, DST, Hartley and Real-DFT are paired with slant transform to generate hybrid slant wavelet transform. Performa...

In the present paper, we generalize Zygmund classes of functions with two variables defined by Móricz by means of modulus of continuity, and give the necessary and sufficient conditions for double sine, sine-cosine, cosinesine and double cosine series so that their sums belong to the generalized Zygmund classes. Some new results of Fülöp [1] and [2] on double trigonometric series are extended.

The Fourier spectra of circular gratings having sine or cosine radial profiles are derived, and their particular properties are discussed. These results are then extended to the most general form of circular sinusoidal gratings, namely: circular sine or cosine gratings with any arbitrary radial phase. q 1998 Elsevier Science B.V.

The Fresnel sine integral S(x), the Fresnel cosine integral C(x), and the associated functions S + (x), S − (x), C + (x), and C − (x) are defined as locally summable functions on the real line. Some convolutions and neutrix convolutions of the Fresnel sine integral and its associated functions with x r + , x r are evaluated. 1. Introduction. The Fresnel integrals occur in the diffraction theory...

The local cosine/sine basis is a localized version of the cosine/sine basis with a window function which can have arbitrary smoothness. It has orthogonality and good time and frequency localization properties. The adaptive local cosine/sine basis is a best-basis obtained from an overabundant library of cosine/sine packets based on a costfunctional. We propose a 2D semi-adaptive (time-adaptive o...

We evaluated the proposal that there exist detectors of the following four cardinal phases in human vision: +cosine, -cosine, +sine, and -sine. First, we assessed whether there was evidence that these cardinal phases were processed by independent 'labeled lines,' using a discrimination at detection threshold paradigm. Second, we assessed whether suprathreshold phase discrimination was best at p...

In this paper, a high-performance all-digital quadrature frequency synthesizer/mixer applied to QAM modulation and demodulation is presented, which synthesizes 12-bit sine and cosine waveforms with a spectral purity of –83.0dB. The synthesizer covers a bandwidth from dc to 100 MHz in steps of 0.0466Hz with a corresponding switching speed of 5 ns at 200MHz clock frequency. Also, it is capable of...