| 摘要 |
PURPOSE:To keep always an optimum contrast by setting automatically the contrast of an ultrasonic tomographic image. CONSTITUTION:A histogram wherein the number of picture elements on each brightness value is made into a graph on an ultrasonic image is prepd. in histogram circuit 28. A width value retrieving circuit 44 obtains a specified width value at a const. height or the prepd. histogram. A circuit 62 for judging rate of increase in width compares the obtd. width value with a specified standard value alpha and the differential increment is output. The circuit 62 for judging rate of increase in width determines the rate of increase in width of contrast based on the obtd. differential increment. The contrast is automatically adjusted thereby in a contrast circuit. |
