UNLABELLED Gated SPECT recorded with 16 intervals determines left ventricular (LV) ejection fraction more accurately than does gated SPECT recorded with 8 intervals but produces higher image noise. This study aimed to assess the results from sestamibi and (201)Tl 16-interval gated SPECT when both signal-to-noise ratio and spatial resolution were enhanced with an original method of reconstructio...

The objective of this paper is to develop an approach to nonlinear ltering which allows the separation of time consuming computations involving the coe cients of the system from those dealing with the observation data only. The approach is based on a Cameron-Martin type expansion for nonnormalized optimal lters. 2

PURPOSE To significantly reduce the background phase effects, especially at the air-tissue interface, and to enhance the desirable local structures of veins in susceptibility-weighted imaging. METHODS In the proposed reconstruction method called Magnitude of Complex Filtering, a complex-valued magnetic resonance image is acquired using a flow-compensated high-resolution 3D gradient-echo seque...

A general linear theory is presented which describes the extension of the convolutional method to nonstationary processes. This theory can apply any linear, nonstationary filter, with arbitrary time and frequency variation, in the time, Fourier, or mixed (time-frequency) domains. The filter application equations and the expressions to move the filter between domains are all ordinary Fourier tra...

In this paper, a comparison between three different filters in the 3D scanning processes by Fourier Transform two-dimensional. The implementation and comparison about the filter by threshold, morphological filtering like rectangle and elliptic, the representation about the filters are in a binary mask and it is multiplied by the spectrum of Fourier Transform two-dimensional, with this process t...

This paper briefly reviews the basics of optical Fourier techniques (OFT) and applications for medical image processing as well as phase contrast imaging of live biological specimens. Enhancement of microcalcifications in a mammogram for early diagnosis of breast cancer is the main focus. Various spatial filtering techniques such as conventional 4f filtering using a spatial mask, photoinduced p...

We introduce a newmultiscale Fourier-based object description in 2-D space using a low-pass Gaussian filter (LPGF) and a high-pass Gaussian filter (HPGF), separately. Using the LPGF at different scales (standard deviation) represents the inner and central part of an object more than the boundary. On the other hand using the HPGF at different scales represents the boundary and exterior parts of ...

This article presents an optical measurement method for acquiring rapidly accurate geometric 3-D surface morphology of objects. To achieve high-speed profilometry and avoid disturbance due to in-field vibration, one-shot Fourier transform profilometry (FTP) using twowavelength digital moiré pattern was developed to detect the morphology of the measured object at a speed of up to 60 frames or mo...

We present a discrete-time mathematical formulation for applying recursive digital filters to non-uniformly sampled signals. Our solution presents several desirable features: it preserves the stability of the original filters; is well-conditioned for low-pass, high-pass, and band-pass filters alike; its cost is linear in the number of samples and is not affected by the size of the filter suppor...

A pair of ear-muffs that employs active noise control (ANC) for noise reduction, substantially reduces the influence of the low frequencies inside the cap. This implies an indirect high-pass filtering of the sound in the external auditory canal (EAC). This paper shows that the above mentioned high-pass filtering property is convenient when combining an ANC headset with an in-ear microphone (ear...