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adapt them to the short-time statistics of the speech. A formal subjective listening trial has shown the method to significantly<br />
improve the perceived quality of block-coded speech.<br />
Author<br />
Voice Data Processing; Coding; Noise Reduction; Adaptive Filters; Linear Prediction; Mean Square Values<br />
20060001705 ITT Defense Communications Div., San Diego, CA, USA<br />
Techniques for Suppression of an Interfering Talker in Co-Channel Speech<br />
Naylor, J. A.; Boll, S. F.; IEEE International Conference on Acoustics, Speech, <strong>and</strong> Signal Processing (ICASSP ‘87); Volume<br />
1; 1987, pp. 6.12.1-6.12.4; In English; See also 20060001583; Copyright; Avail.: Other Sources<br />
The problem addressed by this study is the suppression of an undesired talker when two talkers are communicating<br />
simultaneously on the same monophonic channel (co-channel speech). Two different applications are considered, improved<br />
intelligibility for human listeners, <strong>and</strong> improved performance for automatic speech <strong>and</strong> speaker recognition (ASR) systems.<br />
For the human intelligibility problem, the desired talker is the weaker of the two signals with voice-to-voice power ratios<br />
(Power desired / Power interference), or VVRs, as low as -18dB. For ASR applications, the desired talker is the stronger of<br />
the two signals, with VVRs as low as 5dB. Signal analysis algorithms have been developed which attempt to separate the<br />
co-channel spectrum into components due to the two different (stronger <strong>and</strong> weaker) talkers.<br />
Author<br />
Speech Recognition; Communicating; Human Performance; Signal Analysis; Intelligibility<br />
20060001720 Massachusetts Univ., Amherst, MA, USA<br />
Segmentation of Noisy Textured Images Using Simulated Annealing<br />
SunWon, Chee; Derin, Haluk; IEEE International Conference on Acoustics, Speech, <strong>and</strong> Signal Processing (ICASSP ‘87);<br />
Volume 1; 1987, pp. 563-566; In English; See also 20060001583<br />
Contract(s)/Grant(s): NSF ECS-8403685; ONR N00014-85-K-0561; Copyright; Avail.: Other Sources<br />
This paper presents a segmentation algorithm for noisy textured images. To represent noisy textured images, we propose<br />
a hierarchical stochastic model that consists of three levels of r<strong>and</strong>om fields: the region process, the texture processes <strong>and</strong> the<br />
noise. The hierarchical model also includes local blurring <strong>and</strong> nonlinear image transformation as results of the image<br />
corrupting effects. Having adopted statistlc31 model, the maximum a posteriori (MAP) estimation is used to find the<br />
segmented regions through the restored(noise-free) textured image data. Since the joint a posteriori distribution at h<strong>and</strong> is a<br />
Gibbs distribution, we use simulated annealing as a maximization technique. The simulated annealing based segmentation<br />
algorithm presented in this paper can also be viewed as a two step iterative algorithm in the spirit of the EM algorithm.<br />
Author<br />
Electromagnetic Noise; Algorithms; Mathematical Models; Segments<br />
20060001722 University of Southern Illinois, IL, USA<br />
Invariant Planar Shape Recognition Using Dynamic Alignment<br />
Gupta, L.; Srinath, M. D.; IEEE International Conference on Acoustics, Speech, <strong>and</strong> Signal Processing (ICASSP ‘87); Volume<br />
1; 1987, pp. 7.3.1-7.3.4; In English; See also 20060001583; Copyright; Avail.: Other Sources<br />
A technique for classifying closed planar shapes is described in which a shape is characterized by an ordered sequence<br />
that represents the Euclidean distance between the centroid <strong>and</strong> all contour pixels of the shape. Shapes belonging to the same<br />
class have similar sequences, hence a procedure for classifying shapes is based on the degree of similarity between these<br />
sequences. In order to determine the similarity between sequences, a non-linear alignment process is developed to find the best<br />
correspondence between the sequences. Optimum alignment is obtained by exp<strong>and</strong>ing segments of the sequences to minimize<br />
a dissimilarity function between the sequences. Normalization with respect to scaling <strong>and</strong> rotation is described <strong>and</strong> an example<br />
illustrating the use of dynamic alignment for the classification of noisy shapes is presented.<br />
Author<br />
Shapes; Pixels; Alignment; Classifications; Euclidean Geometry; Contours<br />
20060001734 Texas A&M Univ., College Station, TX, USA<br />
Jump Detection <strong>and</strong> Fast Parameter Tracking for Piecewise AR Processes Using Adaptive Lattice Filters<br />
Li, Shiping; Dickinson, Bradley W.; IEEE International Conference on Acoustics, Speech, <strong>and</strong> Signal Processing (ICASSP<br />
‘87); Volume 1; 1987, pp. 9.2.1 - 9.2.4; In English; See also 20060001583<br />
Contract(s)/Grant(s): NSF ECS-84-05460; AFOSR-84-0381; Copyright; Avail.: Other Sources<br />
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