Method and apparatus for downloading multi-page electronic documents with hint information

摘要

A method and apparatus for providing an optimized page-based electronic document file and downloading the optimized file. An optimized document file is created from a non-optimized electronic document. Page contents are contiguously written in the optimized file and a page offset table is provided in the optimized file that includes page offset information used to locate individual pages and objects of the document. Shared objects, such as fonts, are included in the file after the page contents. When downloading the optimized file from a host, the page offset information is read early and is used to download a specific page requested by the user without downloading other pages in the document. In one embodiment, a viewer downloads a first portion of the requested page, while all remaining portions of the requested page are located and requested by a finder process using the page offset table. In alternative embodiments, all objects for a full page may be requested at once. The requested page can thus be downloaded with only one connection to the host. Shared objects can optionally be downloaded interleaved between portions of the page contents that reference the shared objects. Alternatively, with the use of hint tables, shared and other objects can be read in one transaction identifying byte ranges in the document. The requested page is displayed to the user on an output display device. The order elements are displayed provides quick access to useful information and to active elements.