5. An image forming apparatus, comprising: a text/image separation apparatus to receive data associated with a document that is received and scanned by the image forming apparatus, the document having one or more pages and to determine data for a text area in the one or more pages from the received data associated with the document; an index determination apparatus to determine data for one or more content indicating texts from among the text area in the one or more pages of the document from the received data by selecting characters of the content indicating texts based on comparing a size of characters in the text area with a predetermined size threshold that is set as an average value of preset character properties calculated on a variation of the preset character properties, and grouping selected characters together based on relative proximity to one another; and an index page creation apparatus to create index page data for an index page for the document including the one or more content indicating texts determined from the received data, wherein the index determination apparatus receives data associated with separated symbols of the text area from the text/image separation unit, compares the data associated with separated symbols to one or more predetermined size parameters to determine whether the separated symbols are content indicating symbols, and groups adjacent ones of the content indicating symbols together and determines the grouped content indicating symbols as the content indicating texts for the index page and index page data.
5. An image forming apparatus, comprising: a text/image separation apparatus to receive data associated with a document that is received and scanned by the image forming apparatus, the document having one or more pages and to determine data for a text area in the one or more pages from the received data associated with the document; an index determination apparatus to determine data for one or more content indicating texts from among the text area in the one or more pages of the document from the received data by selecting characters of the content indicating texts based on comparing a size of characters in the text area with a predetermined size threshold that is set as an average value of preset character properties calculated on a variation of the preset character properties, and grouping selected characters together based on relative proximity to one another; and an index page creation apparatus to create index page data for an index page for the document including the one or more content indicating texts determined from the received data, wherein the index determination apparatus receives data associated with separated symbols of the text area from the text/image separation unit, compares the data associated with separated symbols to one or more predetermined size parameters to determine whether the separated symbols are content indicating symbols, and groups adjacent ones of the content indicating symbols together and determines the grouped content indicating symbols as the content indicating texts for the index page and index page data. 14. The image forming apparatus of claim 5 , wherein the index page creation apparatus adds the index page data to the data associated with the document.