Ultrasonic methods of nondestructive evaluation are used extensively in industry owing to the versatility and inherent advantages of the method. A major area of research in ultrasonic NDE is the analysis of reflected waveforms representing the interaction between an ultrasonic wave and inhomogeneties in the material under inspection. The objective of the analysis technique described in this paper is to extract information contained in the signal for estimating the size, shape, and location of the defects. Although full defect reconstruction schemes call for considerable computational effort, defect characterization algorithms based on pattern recognition methods are being increasingly used for signal interpretation.