The time-frequency content of a signal can be measured by the Gabor transform or windowed Fourier transform. This is a function defined on phase space that is computed by taking the Fourier transform of the product of the signal against a translate of a fixed window. The problem of finding signals with Gabor transform that are maximally concentrated within a given region of phase space is discu...

Mittal and Rhoades (1999–2001) andMittal et al. (2006) have initiated the studies of error estimates En( f ) through trigonometric Fourier approximations (TFA) for the situations in which the summability matrix T does not have monotone rows. In this paper, we determine the degree of approximation of a function ̃ f , conjugate to a periodic function f belonging to the weighted W(Lp,ξ(t))-class (p...

This paper considers the proposed algorithm submitted to theMusic Information Retrieval Evaluation eXchange(MIREX) 2011 “AudioMelody Extraction” task. The proposed melody pitch extraction algorithm can be divided into three steps: (1) a spectral analysis using variable length window, (2) a pitch candidate estimation, and (3) a pitch sequence identification. In the first step, the short-time Fou...

We discuss the origins and regions of validity of various near-field diffraction models. The complete Rayleigh–Sommerfeld model is found to accurately represent intensity distributions for axial distances up to and including the location of the aperture, a region where commonly used models fail. We show that near-field diffraction theory can be applied to the refraction of light at an interface...

In this paper, a hybrid approach is proposed for improving the image retrieval accuracy. In the hybrid approach both local and global features of images are combined, which represent the entire aspects of images. Local features are extracted using Fourier descriptors and global features are extracted by means of angular radial transform. The results of combining both these descriptors demonstra...

An aircraft component detection method based on 3D recognition and relative position estimation is proposed in this paper. Direct detection of components that are small parts of an object is difficult for the lack of distinctive features. Since relative position of a component to the main axis of the plane is invariant to 3D transformation, major direction vector is proposed to find search regi...

This paper presents a new sound synthesis method utilizing the features of transitions contained in an existing sound, using spectral data obtained through Short-Time Fourier Transform (STFT) analysis. In this method, spectra obtained from each instantaneous sound are considered as multivariate data, and placed in a vector space, where an evaluation of distances between vectors is performed. As...

The modification methods described in this paper combine characteristics of PSOLA-based methods and algorithms that resynthesize speech from its short-time Fourier magnitude only. The starting point is a short-time Fourier representation of the signal. In the case of duration modification, portions, in voiced speech corresponding to pitch periods, are removed from or inserted in this representa...

We present methods, based on the short time Fourier transform, which may be used to analyze the structure of multicomponent FM modulated signals instantaneously in time and frequency. The methods build on previously presented cross-spectral methods. In this paper, we introduce the concept of higher order short time Fourier transform phase derivatives, which may be used to estimate signal trajec...

This paper described the relationship between EEG signals and MI in BCI system. EEG signals are used to classify the direction of motioninto two kinds: left and right. We extracted features from original EEG data using STFT and put them into CNN. The result showed that the framework of STFT-CNN had higher average test accuracy. Furthermore, the generations of motor imagery were analyzed, and th...