1. A method comprising: receiving a page request for a requested document, the requested document specifying a plurality of first images as being presentable within the requested document; identifying a second portion of the plurality of first images being positioned further away from the top of the requested document relative to a first portion of the plurality of first images; generating a modified document by modifying the requested document in response to the receiving of the page request, the modified document specifying a second image and a third image, the second image to be generated based on the first portion of the plurality of first images, the third image to be generated based on the second portion of the plurality of first images; generating the second image from the first portion of the plurality of first images based on the page request for the requested document, the generating of the second image being performed using a processor of a machine; generating the third image from the second portion of the plurality of first images; identifying the second image includes the plurality of the first images having a higher priority than the third image based on the position of the images on the requested document; providing the modified document and the second image in response to the received page request for the requested document; and after a time delay from the providing of the second image, initiating a provision of the third image at a data transfer rate slower than the providing of the second image based on the second image having a higher priority than the third image.