Final answer:
To remove imperfections from bitmap or raster images, photo editing software like Adobe Photoshop, which includes tools such as the clone stamp and healing brush, should be used.
Step-by-step explanation:
To touch up photographs and remove scratches and other imperfections of bitmap or raster images, we should use photo editing software such as Adobe Photoshop or GIMP. These programs offer a variety of tools that can be used to repair imperfections by manipulating the pixels of the image to blend and correct the damaged areas. For example, the clone stamp tool can be used to copy pixels from one part of an image to another, effectively covering scratches or blemishes. Additionally, the healing brush tool can blend the imperfections into the surrounding imagery to create a seamless repair.