Advances in the Characterization and Modeling of Civil Engineering Materials Using Imaging Techniques

Abstract

Digital-image processing and analysis is concerned with the transformation and analysis of pictures by a computer. The process starts with the capture of a digital image ~usually referred to as imaging! followed by its storage, transmission, processing, and analysis of the image by a computer to extract information or features of interest. Examples of the type of transformations and extracted features include statistical moments, Fourier coefficients, distance measure, wavelet coefficients, and statistical model parameters. Because of the large size of image data, the history of image processing is closely tied to the advances in digital computing technology in terms of processors, memory, storage, transmission, display, and printing. Modern digital-image processing can be considered to have begun in the 1960s with the arrival of the first computers powerful enough to perform meaningful image processing tasks. Early applications of image processing were in the fields of medical imaging, astronomy, and remote sensing. Invention of the computerized axial tomography ~CAT or CT for short! in the 1970s was a major development in the application of image processing to medical diagnosis. CT provides the ability to image a particular cross section of an object and is used extensively in medical diagnosis and nondestructive testing of materials. Development of different imaging modalities has also helped the advancement of digital-image processing and analysis techniques and has broadened the field of applications. Applications of visible-light imaging include industrial inspection, automatic character recognition, fingerprint analysis, mail sorting, and license plate reading. Besides imaging using visible light, gammaray imaging in medicine, X-ray imaging in industrial applications, ultraviolet imaging in microscopy, infrared imaging in remote sensing, magnetic-resonance imaging ~MRI! in medicine, and ultrasound imaging in medicine are some of the other imaging modalities. The advent of computer technology has created an unprecedented opportunity for the growth of digital-image processing