Overlaying advertisement on optimum images in electronic documents to be displayed on the internet, wherein the electronic document includes at least one image. Image parameters associated with the at least one image in the electronic document are processed to obtain an optimum image, and the advertisement is overlaid on the optimum image, such that it overlaps with the optimum image. The optimum image may be determined by an image recognition engine based on at least one object in the image identified by the image recognition engine, or based on object information obtained from a tagging module. The advertisement may refer to the object. The advertisement may be selected based on contextual information associated with the electronic document. The advertisement may be any of a graphic, a video, and a text.