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Algorithms developed with a Gaussian noise assumption perform poorly in impulsive noise, such as that described by the symmetric [alpha]-stable (S[alpha]S) distribution. We investigate the performance of antipodal signaling and Viterbi decoding of convolutional codes in S[alpha]S noise. We demonstrate that the p-norm branch metric is robust in S[alpha]S noise. Index Terms--Convolutional codes, impulse noise, Viterbi decoding.

Laser speckle imaging has increasingly become a viable technique for real-time medical imaging. However, the computational intricacies and the viewing experience involved limit its usefulness for real-time monitors such as those intended for neurosurgical applications. In this paper, we propose a new technique, tLASCA, which processes statistics primarily in the temporal direction using the laser speckle contrast analysis (LASCA) equation, proposed by Briers and Webster. This technique is thoroughly compared with the existing techniques for signal processing of laser speckle images, including, the spatial-based sLASCA and the temporal-based modified laser speckle imaging (mLSI) techniques, sLASCA is an improvement of the basic LASCA technique. In sLASCA, the derived contrasts are further averaged over a predetermined number of raw speckle images. mLSI, on the other hand, is the technique in which temporal statistics are processed using the equation described by Ohtsubo and Asakura. tLASCA preserves the original image resolution similar to mLSI. tLASCA outperforms sLASCA (window size M = 5) with faster convergence of K values (5.32 versus 20.56 s), shorter per-frame processing time (0.34 versus 2.51 s), and better subjective and objective quality evaluations of contrast images, tLASCA also outperforms mLSI with faster convergence of K values (5.32 s) compared to N values (10.44 s), shorter per-frame processing time (0.34 versus 0.91 s), smaller intensity fluctuations among frames (8%-10% versus 15%-35%), and better subjective and objective quality evaluations of contrast images. As laser speckle imaging becomes an important tool for real-time monitoring of blood flows and vascular perfusion, tLASCA is proven to be the technique of choice. Index Terms--Blood flow and perfusion, laser speckle imaging, medical image processing, subjective and objective quality, time-varying speckle.

A set of orthogonal moment functions is described, based on discrete Tcheichef polynomials. The basic functions are orthogonal in the domain of the image coordinate space, eliminating the need for discrete approximation in numerical implementation.

A method for designing perfect-reconstruction M-channel integer-modulated filter banks (IMFB's) is proposed. Given the filter coefficient word length, many IMFB's satisfying the perfect reconstruction conditions can be obtained. Methods to select the best IMFB for the purpose of image compression are studied, and it is demonstrated that the IMFB obtained by maximizing the coding gain is the most suitable for image coding. Simulation results show that the PSNR of the integer-modulated FIR filter bank designed by maximizing the coding gain with the AR(1) model is close to that of the real-valued cosine-modulated filter bank of the same order. Index Terms - Image compression, M-channel filter banks, perfect reconstruction, wavelet transform.

A domain operator for binary morphological processing used extensively in image processing and computer vision applications is described. The domain operator is a single-parameter tuning method and the operation is more flexible because it has more general operations. The operator is used for edge detection in a noisy image and digital clump detection. Other uses, especially is a nuclear segmentation system, are described.

Contrary to one of the key conclusions of the above paper,(1) the cross-correlation of the 1-D SA-DCT coefficients located in two columns of different sizes does not necessarily take maximum values at the same indices. The correct way to measure the cross-correlation of the SA-DCT coefficients after the first stage of the transform is presented in this letter. The idea of implementing shape-adaptive DCT and some aspects of their work could nevertheless be useful.