We have developed a physically-intuitive method to calculate the local lattice constant as a function of position in a high-resolution transmission electron microscopy image by performing a two-dimensional fast Fourier transform. We apply a Gaussian filter with appropriate spatial full-width-half-max (FWHM) bandwidth to the image centered at the desired location to calculate the local lattice c...

Ultrasonic flow estimation involves Fourier-transforming data from successive pulses. The standard periodogram spectral estimate does not reflect the true velocity distribution in the blood and assumes quasi-stationarity in the data. Last year [l], we demonstrated that a recursive lattice filter can yield results much closer to the correct velocity distribution. We have now implemented it in re...

We present a filter design scheme in which we use an all-fiber lattice filter to equalize Gaussian-like spectra. With a two-step design strategy, the designed equalization filter can flatten the Gaussian-like spectra in the maximally flat sense, and the spectrum ripples can be assessed quantitatively. The equalization performance is analyzed theoretically. It is also shown that the equalization...

This paper concerns the construction of highly symmetric compactly supported wavelets for hexagonal data/image and triangle surface multiresolution processing. Recently hexagonal image processing has attracted attention. Compared with the conventional square lattice, the hexagonal lattice has several advantages, including that it has higher symmetry. It is desirable that the filter banks for he...

Wave digital filter (WDF) structures for high-speed narrow-band and wide-band filtering are introduced. The narrow-band filter is composed of a periodic model filter and one or several, possibly periodic, masking filters in cascade. Lattice and bireciprocal lattice WDF filters are used for the model and masking filters, respectively. The wide-band filter consists of a narrow-band filter in para...

This paper studies the construction of highly symmetric compactly supported wavelets for hexagonal data/image and triangle surface multiresolution processing. Recently hexagonal image processing has attracted attention. Compared with the conventional square lattice, the hexagonal lattice has several advantages, including that it has higher symmetry. It is desirable that the filter banks for hex...