A method of generating an image, comprising: launching a first ultrasonic plane wave from a plane wave generator toward a platen surface; acquiring a first set of pixel output signals at a first acquisition time that is delayed from the launch of the first ultrasonic plane wave by a first acquisition time delay, each pixel output signal from the first set of pixel output signals representing a local magnitude at a sensor pixel array of the first ultrasonic plane wave reflected from the platen surface; launching a second ultrasonic plane wave from the plane wave generator toward the platen surface; acquiring a second set of pixel output signals at a second acquisition time that is delayed from the launch of the second ultrasonic plane wave by a second acquisition time delay, each pixel output signal from the second set of pixel output signals representing a local magnitude at the sensor pixel array of the second ultrasonic plane wave reflected from the platen surface; the method being characterized by generating a corrected output signal for a selected pixel of the sensor pixel array based on a selected output signal from the first set of pixel output signals and on first-level correction signals from the second set of pixel output signals, wherein the selected output signal corresponds to the selected pixel and the first-level correction signals correspond to a first set of neighboring pixels near the selected pixel, wherein a difference between the first acquisition time delay and the second acquisition time delay corresponds to a mean distance between the selected pixel and the first set of neighboring pixels. launching a first ultrasonic plane wave from a plane wave generator toward a platen surface; acquiring a first set of pixel output signals at a first acquisition time that is delayed from the launch of the first ultrasonic plane wave by a first acquisition time delay, each pixel output signal from the first set of pixel output signals representing a local magnitude at a sensor pixel array of the first ultrasonic plane wave reflected from the platen surface; launching a second ultrasonic plane wave from the plane wave generator toward the platen surface; acquiring a second set of pixel output signals at a second acquisition time that is delayed from the launch of the second ultrasonic plane wave by a second acquisition time delay, each pixel output signal from the second set of pixel output signals representing a local magnitude at the sensor pixel array of the second ultrasonic plane wave reflected from the platen surface; the method being characterized by generating a corrected output signal for a selected pixel of the sensor pixel array based on a selected output signal from the first set of pixel output signals and on first-level correction signals from the second set of pixel output signals, wherein the selected output signal corresponds to the selected pixel and the first-level correction signals correspond to a first set of neighboring pixels near the selected pixel, wherein a difference between the first acquisition time delay and the second acquisition time delay corresponds to a mean distance between the selected pixel and the first set of neighboring pixels.