5. The method of claim 3 , wherein extracting physical attributes of the scanned document comprises detecting the margin smoothness of the processed scanned document.
6. The method of claim 5 , wherein detecting the margin smoothness of the processed scanned document comprises calculating a jig jag degree (D jig-jag ) by computing an average position of a margin of the document, computing a standard deviation of the margin, converting the margin into a sequence of numbers with values of 0, −1, and 1 as follows: X i = { - 1 if ⁢ ⁢ x i < μ 0 if ⁢ ⁢ x i = μ 1 if ⁢ ⁢ x i > μ , counting the total number N seq of continuous 1, −1, and 0 sequences in the converted number sequence, and computing D jig-jag as: D jig ⁢ - ⁢ jag = { 100 if ⁢ ⁢ σ ≥ 100 σ if ⁢ ⁢ σ < 100 0 if ⁢ ⁢ σ < T .