The two-dimensional discrete cosine transform (DCT) can be found in the heart of many image compression algorithms. Specifically, the JPEG format uses a lossy form of compression based on that transform. Since the standardization of the JPEG, many other transforms become practical in lossy data compression. This article aims to analyze the use of these transforms as the DCT replacement in the J...

Fast trigonometric transforms and periodic orthogonal wavelet transforms are essential tools for numerous practical applications. It is very important that fast algorithms work stable in a floating point arithmetic. This survey paper presents recent results on the worst case analysis of roundoff errors occurring in floating point computation of fast Fourier transforms, fast cosine transforms, a...

This paper presents a efficient non iterative wavelet based image deblocking method which employs a maximum a posteriori (MAP) estimator that uses the Laplace probability density function with local variance to smooth out the blocking artifacts in block discrete cosine transform (DCT) compressed images. We have shown that the noise standard deviation has a strong relationship with the average o...

Images can be compressed in multiple ways. The new JPEG2000 standard uses an algorithm called EBCOT and the Discrete Wavelet Transform, while the ordinary JPEG standard uses the Discrete Cosine Transform (DCT). Other compression methods use frequency-domain analysis with Gabon Filters, Radon Filters and other Wavelet Filters. Sim et al.[2] present an algorithm for obtaining texture descriptors ...

The finger knuckle print (FKP) of a particular person is found to be unique and can serve as a biometric feature has been revealed recently by the researchers. In this paper finger knuckle print will be used as a biometric feature. The databaseImages from Hong KongPolytechnic Universitywere processed using Kekre’s hybrid wavelet type 1 and type 2 for the generation of results. Kekre’s hybrid wa...

This paper presents a no-reference image quality assessment metric that makes use of the wavelet subband statistics to evaluate the levels of distortions of wavelet-compressed images. The work is based on the fact that for distorted images the correlation coefficients of the adjacent scale subbands change proportionally with respect to the distortion of a compressed image. Subband similarity is...

A new adaptive Packet algorithm based on Discrete Cosine harmonic wavelet transform (DCHWT), (DCAHWP) has been proposed. This is realized by the Discrete Cosine Harmonic Wavelet transform (DCHTWT) which exploits the good properties of DCT viz., energy compaction (low leakage), frequency resolution and computational simplicity due its real nature, compared to those of DFT and its harmonic wavele...