2. The apparatus of claim 1 wherein the processor is further configured to: determined whether a present character has the same text properties as an adjacent character with respect to characters on each line or column of the text graphic unit data, wherein when the determination result is Yes, the present character is saved into a text node corresponding to the adjacent character.
2. The apparatus of claim 1 wherein the processor is further configured to: determined whether a present character has the same text properties as an adjacent character with respect to characters on each line or column of the text graphic unit data, wherein when the determination result is Yes, the present character is saved into a text node corresponding to the adjacent character. 3. The apparatus of claim 2 wherein the processor is further configured to: create a new text node when the determination result is No, and save the present character into the newly created text node.