A wavelet ridge extraction method employing a novel cost function in two-dimensional wavelet transform profilometry

A Fast Localization and Feature Extraction Method Based on Wavelet Transform in Iris Recognition

With an increasing emphasis on security, automated personal identification based on biometrics has been receiving extensive attention. Iris recognition, as an emerging biometric recognition approach, is becoming a very active topic in both research and practical applications. In general, a typical iris recognition system includes iris imaging, iris liveness detection, and recognition. This rese...

Two-dimensional quaternion wavelet transform

In this paper we introduce the continuous quaternion wavelet transform (CQWT). We express the admissibility condition in terms of the (right-sided) quaternion Fourier transform. We show that its fundamental properties, such as inner product, norm relation, and inversion formula, can be established whenever the quaternion wavelets satisfy a particular admissibility condition. We present several ...

Ridge extraction algorithms for one-dimensional continuous wavelet transform: a comparison

Quantitative Dip Bounds for the Two-dimensional Discrete Wavelet Transform the Two-dimensional Discrete Wavelet Transform

An analysis of the discrete wavelet transform of dipping segments with a signal of given frequency band leads to a quantitative explanation of the known division of the two-dimensional wavelet transform into horizontal, vertical and diagonal emphasis panels. The results must be understood in a \fuzzy" sense: since wavelet mirror lters overlap, the results stated can be slightly violated with vi...

Analyzing laser plasma interferograms with a continuous wavelet transform ridge extraction technique: the method.

Laser plasma interferograms are currently analyzed by extraction of the phase-shift map with fast Fourier transform (FFT) techniques [Appl. Opt. 18, 3101 (1985)]. This methodology works well when interferograms are only marginally affected by noise and reduction of fringe visibility, but it can fail to produce accurate phase-shift maps when low-quality images are dealt with. We present a novel ...