Direct observation of Gouy phase shift on an optical vortex was presented through investigating the intensity profiles of a modified LG_p;m beam with an asymmetric defect, around at the focal point. It was quantitatively found that the rotation profile of a modified LG_p;m beam manifests the Gouy phase effect where the rotation direction depends on only the sign of topological charge m. This pr...

Invariant object recognition is maybe the most basic and fundamental property of our visual system. It is the basis of many other cognitive tasks, like motor actions and social interactions. Hence, the theoretical understanding and modeling of invariant object recognition is one of the central problems in computational neuroscience. Indeed, object recognition consists of two different tasks: cl...

A fundamental problem in machine vision is the classification of objects which may have unknown position, orientation, or a combination of these and other transformations. The massive amount of data required to accurately form an appearance-based model of an object under all values of shift and rotation transformations has discouraged the incorporation of the combination of both transformations...

Rotational kinematics of the knee is not fully restored after single-bundle anterior cruciate ligament (ACL) reconstruction. Cadaveric experiments using knee testing machines have suggested anatomical reconstruction replacing the anteromedial and posterolateral bundles could restore knee kinematics more effectively than single-bundle reconstruction. However, practical tools to objectively asses...

We present a novel image feature descriptor for rotationally invariant 2D texture classification. This extends our previous work on noise-resistant and intensity-shift invariant median binary patterns (MBPs), which use binary pattern vectors based on adaptive median thresholding. In this paper the MBPs are hashed to a binary chain or equivalence class using a circular bit-shift operator. One bi...

Shift and rotation invariance properties of linear time-frequency representations are investigated. It is shown that among all linear time-frequency representations, only the short-time Fourier transform (STFT) family with the Hermite–Gaussian kernels satisfies both the shift invariance and rotation invariance properties that are satisfied by the Wigner distribution (WD). By extending the time-...

Farsi Handwriting Word Recognition (FHWR), especially those with different orientation and scale changes as well as different handwriting style, is a challenging and important problem in document image analysis. This paper proposes a holistic FHWR scheme using local features of M-Band packet wavelet. The rotation and scale invariant local feature extraction for a given word image involves apply...

In this paper the implementation of Kogbetliantz's SVD algorithm using orthonormal {rotations is presented. An orthonormal {rotation is a rotation by an angle of a given set of {rotation angles (e.g. the angles i = arctan 2 ?i) which are choosen such that the rotation can be implemented by a small amount of shift{add operations. All computations (evaluation and application of the rotations) can...

Rotational Fresnel drag - or orbital Faraday rotation in a rotating magnetised plasma is uncovered and studied analytically for Trivelpiece-Gould Whistler-Helicon waves carrying angular momentum (OAM). Plasma shown to introduce non-zero phase shift between OAM-carrying eigenmodes with opposite helicities, similarly the phase-shift spin associated classical effect at rest. By examining dispersio...

The use of the constant-deviation prism for producing monochromatic light introduces the problem of image shifts that result from rotating the prism when changing from one spectral line to another. The magnitudes of both the lateral and the axial components of this shift, for a given rotation of the prism, depend upon the position of the axis about which the prism rotates. A position for the ax...