During digital image processing, which technique can enhance the visibility of structures by using different energies?

Energy subtraction is a technique used in digital image processing to enhance the visibility of structures by utilizing different energies of x-ray exposure. This process involves taking two or more images of the same area but with varying energy levels; typically, one image is captured at a lower energy level while another is captured at a higher energy level. The lower energy image tends to be more sensitive to certain tissues or structures, while the higher energy image may penetrate through some of those structures, thereby providing different contrast levels.

When the images are processed through energy subtraction, the resultant image emphasizes the differences between the tissues. This method can effectively highlight certain anatomical structures that may be obscured or less visible when using a single energy level. This is particularly useful in applications such as mammography or vascular imaging, where distinguishing between types of tissue is crucial for accurate diagnosis.

The other options, while pertinent to image processing, do not specifically leverage the concept of utilizing dual energy levels to enhance visibility in the same manner as energy subtraction.