Patent ID: 7509452

Claim:
An image forming apparatus including hardware resources to use for an image forming process, at least one program for conducting a process concerning an image formation, and a hard disk for recording information including an image, said image forming apparatus comprising: a plurality of hard disk clusters each cluster including erase information indicating whether or not the cluster has been designated for erasure; an erase information map configured to manage the plurality of erase information each showing whether or not to erase data for the corresponding hard disk cluster; an erase information grouping part configured to group the erase information into a plurality of sections, each section including a portion of the plurality of hard disk clusters; an erase count information table configured to manage erase count information for each section, the erase count information being determined for each section based on the erase information of the plurality of hard disk clusters in the respective section, wherein the erase count information indicates a number of hard disk clusters designated for erasure in the respective section; an erase determining part determining, based on the erase count information, whether or not there are any hard disk clusters including erase information indicating that the hard disk cluster is designated for erasure included in each of the plurality of sections; and an erasing part configured to erase each hard disk cluster that includes erase information indicating that the hard disk cluster is designated for erasure in each of the plurality of sections having at least one hard disk cluster designated for erasure when it is determined by the determining part that the respective section includes at least one hard disk cluster designated for erasure.