This paper discusses our ongoing efforts to characterize dust-enshrouded Wolf-Rayet (WR) stars in the radio and infrared. We have used the Very Large Array to measure the broadband radio spectrum of WR stars in suspected binary systems and discovered non-thermal emission, which is usually attributed to colliding winds. In addition, infrared imaging using aperture masking interferometry on the K...

This project examines the problem of single channel blind dereverberation. After estimating the T60 value, a time-domain binary masking approach was used to remove regions of the signal that were largely dominated by reverberant energy. Performance of the system was examined for several different classes of audio (hand clapping, drums, and speech) and for varying amounts of reverberation. In ad...

Convolutional Neural Network (CNN) is a very powerful approach to extract discriminative local descriptors for effective image search. Recent work adopts fine-tuned strategies to further improve the discriminative power of the descriptors. Taking a different approach, in this paper, we propose a novel framework to achieve competitive retrieval performance. Firstly, we propose various masking sc...

A common strategy for sparse linear regression is to introduce regularization, which eliminates irrelevant features by letting the corresponding weights be zeros. However, regularization often shrinks the estimator for relevant features, which leads to incorrect feature selection. Motivated by the above-mentioned issue, we propose Bayesian masking (BM), a sparse estimation method which imposes ...

Time-frequency masking is often used for source separation of underdetermined audio mixtures. It depends on the fact that the sources can be represented disjointly in some transform domain. The focus of this paper is on demixing sources from instantaneous, two-channel mixtures by binary masking. We investigate trees of local cosine bases from which a suitable transform may be generated—the best...

Separating speech signals of multiple simultaneous talkers in a reverberant enclosure is known as the cocktail party problem. In real-time applications online solutions capable of separating the signals as they are observed are required in contrast to separating the signals offline after observation. Often a talker may move, which should also be considered by the separation system. This work pr...

This paper presents a novel data-hiding scheme for multimedia data using non-negative matrix factorization (NMF). Nonnegative feature space (basis matrix) is estimated using the NMF-framework from the sample set of multimedia objects. Subsequently, using a secret key a subspace (basis vector) of the estimated basis matrix is used to decompose the host data for information embedding and detectio...

In a reverberant enclosure, acoustic speech signals are degraded by reflections from walls, ceilings, and objects. Restoring speech quality and intelligibility from reverberated speech has received increasing interest over the past few years. Although multiple channel dereverberation methods provide some improvements in speech quality/intelligibility, single-channel dereverberation remains an o...

We used a noise masking technique to test the hypothesis that detection is subserved by only two chromatic postreceptoral mechanisms (red-green and blue-yellow) and one achromatic (luminance) mechanism. The task was to detect a 1-c/deg Gaussian enveloped grating presented in a mask of static, spatially low-passed binary or Gaussian distributed noise. In the main experiment, the direction of the...