Several adaptive order statistic filters (OSF) are developed and compared for channel characterization and noise suppression in images and 3-D CT data. Emphasis has been put on the situation when a noisefree reference image is not available but instead we can have a sequence of two noisy versions of the same image (or a 3-D data slice). One of the noisy images is used as the reference in the OS...

This paper considers the problem of two-channel speech enhancement with a single target speaker in a diffuse noise field and proposes a novel algorithm for estimating the power spectral density (PSD) of the background noise. First, a reference noise signal is computed as the output of a blocking matrix based on blind source separation (BSS). Then the ratio between the target noise PSD and the r...

This paper studies the problem of full reference visual quality assessment of denoised images with a special emphasis on images with low contrast and noise-like texture. Denoising of such images together with noise removal often results in image details loss or smoothing. A new test image database, FLT, containing 75 noise-free ‘reference’ images and 300 filtered (‘distorted’) images is develop...

In a phase-locked loop (PLL), it is critical to understand how reference clock noise affects the output quality, particularly in applications where PLLs are cascaded. That is, where the output of one PLL serves as the reference clock for another PLL. Traditionally, this problem is solved by qualitative analyses, rules of thumb, and simulation, all of which require confirmation with measurements...

An automated visual printed circuit board (PCB) inspection system proposed in this paper is designed specifically to detect various types of defects occurred during circuit printing process in manufactory. Two-dimensional HAAR wavelet transform is incorporated in the PCB inspection algorithm of the inspection system. During the inspection, two type of images are required; reference and tested P...

We investigated the sensitivity of the gamma index to two factors: the spatial resolution and the noise level in the measured dose distribution. We also examined how the choice of reference distribution and analysis software affect the sensitivity of gamma analysis to these two factors for quality assurance (QA) of intensity-modulated radiation therapy (IMRT) treatment plans. For ten clinical I...

Jacobian Adaptation (JA) of the acoustic models is a fast adaptation technique that has been used in Automatic Speech Recognition (ASR) systems to adapt the models from the training to the testing noise conditions. This technique has been tested in previous works with both Mel-Frequency Cepstrum Coefficients (MFCC) and Frequency Filtering (FF) parameters and good speech recognition results were...

This study examines the relation between a static and a dynamic measure of interaural correlation discrimination: (1) the just noticeable difference (JND) in interaural correlation and (2) the minimum detectable duration of a fixed interaural correlation change embedded within a single noise-burst of a given reference correlation. For the first task, JNDs were obtained from reference interaural...

Codebook-based single-microphone noise suppressors, which exploit prior knowledge about speech and noise statistics, provide better performance in nonstationary noise. However, as the enhancement involves a joint optimization over speech and noise codebooks, this results in high computational complexity. A codebook-based method is proposed that uses a reference signal observed by a bone-conduct...