Method for Acquisition of Camera Document Images' Distorted Gradient

Dewarping of camera document images has attracted a lot of interest over the last few years since warping not only reduces the document readability but also affects the accuracy of an OCR application. In this paper, approach for efficient getting distorted gradient of camera document images is presented. The gradient of text lines can be got by scanning black pixels’ number in text. For avoiding only getting error gradient, the image is divided into 6 zones. In each zone, a gradient is found out. Then, the dewarping can be achieved by projective transformation. Experimental results on several document images demonstrate the robustness and effectiveness of the proposed technique.

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