The use of ultrasonography as an imaging modality has become widespread because of its ability to visualize the organs with no deleterious effects and low cost. Using ultrasonic liver images focal diseases can be identified by differences in echogenicity between normal and areas affected by diseases. In the presence of diffused disease, however, the entire organ may be affected. In that situation, there is no contrast in echo intensity on which to base a diagnosis. Hence it is difficult for an experienced clinician to diagnose the diffused liver diseases by simple visual interpretations. This can be improved by providing useful information, obtained by computer aided tissue characterization, that cannot be obtained by simple visual interpretation.
Many researchers have studied the problem of liver tissue characterization. It is difficult to classify human body organ tissues using shape or gray level information because the shape of each organ is not consistent throughout...