Hi Nightshade, they are purely called 'digital images or pictures'. We had this discussion on a photography forum that I'm a member of, and here is my reasoning behind my answer...
Photograph n. a picture formed by means of the chemical action of light or other radiation on sensitive film.
Picture n. (often
attrib.) a painting, drawing, photograph, etc., esp. as a work of art.
Image n. An optical appearance or counterpart produced by light or other radiation from an object reflected in a mirror, refracted through a lens, etc.
Ian G