The use of visual representations in which pixel-size and local neighborhood topology are not constant is termed space-variant vision. This is the dominant visual architecture in all higher vertebrate visual systems, and is coming to play an important role in real-time active vision applications in the form of log-polar, foveating pyramid, and related approaches to machine vision. The breaking ...

Rotation, Shifting, and Translation (RST) invariant image watermarking is a very important research topic. In this letter, we report a new filtering method in the log-polar mapping (LPM), and a novel rectification method that can be used in any RST invariant image watermarking algorithms. We get a log-polar mapping of an image by calculating the Fourier transform of the image and resampling the...

Ariicial vision systems for mobile robots necessitate sensors and representations that enable a real-time reactive behavior. The log-polar transform has been shown to be a variable resolution scheme that achieves a high compression of the non-foveal part of an image. Such space variant sensors must inevitably be active in order to utilize the high-and homogeneous resolution fovea. We study here...

We present the concept that for uniformly rotated images, the optimal approximation of the images can be obtained by computing the basis vectors for the discrete cosine transform (DCT) of the original image in polar coordinates, and that the images can be represented as linear combinations of the basis vectors.

This paper presents a method to decompose binary shapes into connected parts, based on their structure, as captured by the eccentricity transform. This decomposition is then used in a graph pyramid framework for mapping a polar-like coordinate system to a non-rigid shape. Initial experimental results are presented.

The coefficients of the Angular Radial Transform (ART) are used as MPEG-7 Shape descriptors where the bases functions ART are defined in polar coordinates over a unit disk. Conventional computational methods for computing the ART coefficients are depending on a circular to square mapping which produce two kinds of errors and results in inaccurate set descriptors. This work proposes accurate and...

The extended Golay code is shown to be representable as a chained polar subcode. This enables its decoding with the successive cancellation decoding algorithm and its stack generalization. The decoder can be further simplified by employing fast Hadamard transform. The complexity of the obtained algorithm is comparable with that of the Vardy algorithm.

Let T be an adjointable operator on a Hilbert $$C^*$$ -module such that has the polar decomposition $$T=U\vert T\vert $$ . For each natural number n, is called $$(n+1)$$ -centered if $$T^k=U^k\vert T^k\vert for $$1\le k\le n+1$$ This paper initiates study of via generalized Aluthge transform and iterative transform. Some new characterizations are provided.

A new technique is reported for the transformation of smooth nonpolar ZnO nanowire surfaces to zigzagged high-index polar surfaces using polycrystalline ZnO thin films deposited by atomic layer deposition (ALD). The c-axis-oriented ZnO nanowires with smooth nonpolar surfaces are fabricated using vapor deposition method and subsequently coated by ALD with a ZnO particulate thin film. The synthes...