Signature line detection in scanned documents
In this paper, we present an algorithm to determine the signature line in scanned documents through a fast and computationally efficient technique. To that effect, the algorithm consists of three modules, namely pre-processing, candidate line detection and classification. Preprocessing in this case consists of hard thresholding, which is essential to line detection in the next module. The Hough transform for a single angle (horizontal) is utilized in the line detection module. Connected component analysis is utilized to merge detected Hough lines belonging to the same line on the document. Finally, the classification module attempts to classify each line as a signature line or not. This is accomplished using Histogram of a Gradient (HoG) features and a Euclidean distance measure for comparison. Prior data for this similarity comparison consists of images of target text in different font sizes and styles. The proposed algorithm showed favorable results in terms of precision and accuracy.