1. A method for extracting a raster image of a page from a portable electronic document, comprising: (a) acquiring commands and resources of the raster image of the page by analyzing a format of the portable electronic document; (b) extracting first and second candidate raster images by processing the commands and the resources of the raster image of the page; (c) integrating the first and second candidate raster images as an integrated candidate raster image provided that the first and second candidate raster images are linked together; and (d) removing a pseudo-raster image from the integrated candidate raster image.