Generating multiple digital images with changed aspect ratio

In an embodiment, a data processing method comprises receiving and storing one or more original graphic image files; for each particular original graphic image file among the graphic image files: determining a first aspect ratio of the particular original graphic image file; determining whether the first aspect ratio is wider, taller, or identical to a specified second aspect ratio associated with one or more target image files; creating and storing the one or more target image files each having the second aspect ratio, by re-sampling the particular original graphic image file to match a first dimension of the one or more target image files, and selectively cropping one or more portions of the particular original graphic image file to form the one or more target image files having the second aspect ratio; wherein the method is performed using one or more computing devices.