This paper presents a technique used to choose optimal wavelets for electrocardiogram (ECG) signal data compression. At present, it is not clear which wavelet function is suitable for data compression of ECG signals. An important issue is that the performance of wavelet based algorithms may depend on the particular basis chosen for the signal compression. Various criteria are used to evaluate the fidelity of the reconstruction. The percent root difference (PRD) has been widely used in the literature as the principal error criterion. In this paper, three more criteria are used, namely, signal to noise ratio (SNR), distortion (D), and root mean square error (RMSE). We use a multiwavelet system that can simultaneously provide perfect reconstruction while preserving length (orthogonality), good performance at boundaries (via linear-phase symmetry), and high order of approximation (vanishing moments). Experimental results are shown for both multiwavelets and scalar wavelets.

Two simple and fast block truncation coding algorithms which require reduced bit rates are presented in this paper. The proposed algorithms are compared with the modified block truncation coding technique (MBTC) with regard to the mean square error (MSE), bit rates and subjective quality of the reconstructed images. It is found that the results obtained with the proposed algorithms at reduced bit rates are comparable to those obtained with the MBTC. Further, it is shown that one of the proposed algorithms yields results which are comparable to those achieved with more complex hybrid algorithms.

A new look-up table technique for the coding of the block truncated image bit plane is presented which yields better images in the subjective as well as in the mean square sense compared to the one proposed by Mitchell and Delp (1980).>

An optimization technique for the design of two types of multiple-valued PLAs is described. In a type-I PLA, the multiple-valued function is realized directly, whereas in a type-II PLA, output encoding is used to encode the binary output of the PLA. In both types, multiple function literal circuits are used for the purpose of minimization. It is shown that the proposed technique leads to a considerably reduced size of PLA when compared to the earlier techniques.>

Digital filter structures based on the concept of a generalized emittance converter (GIC) are proposed. These structures are shown to possess better sensitivity and noise properties than known GIC structures. The comparison study is carried out using different types of sensitivity and noise measures.>