1. A method for capturing a workflow history of an electronic document, the method comprising: storing an array having a plurality of slots that each corresponds to a different cell in a plurality of cells, wherein each cell in the plurality of cells is associated with a different spatial subdivision of an image represented by the electronic document and includes one or more pixels included in the image; receiving an event generated by an application that is configured to modify at least one pixel corresponding to at least one cell in the plurality of cells; generating a data object that includes information related to the event; capturing a digital image that reflects a state of the document at a point in the workflow history of the document corresponding to when the application generated the event; storing the data object and the digital image in a memory; and storing a pointer to the data object in each slot in the array that corresponds to a cell of the document that is modified as a result of the event.