System and Method for Scanned Document Correction

摘要

A system and method are provided for the correction of a warped page image. The method first accepts a camera image of a page, creates a filtered edge map, and identifies text-likely regions. The filtered edge map and text-likely regions are projected into a polar coordinate system to determine page lines and warped image page curves. An adaptive two-dimensional (2D) ruled mesh piecewise planar approximation of a warped page surface is created. A three-dimensional (3D) model is created using the adaptive 2D ruled mesh and the estimate of the camera focal length estimate. Using the 3D model, a 2D target mesh is created for rectifying the image of the page. In one aspect, the adaptive 2D ruled mesh is projected onto a 3D warped page surface using the estimated camera focal length and an estimated surface normal of each planar strip from the adaptive 2D ruled mesh.

主权项

1. A method for the correction of a warped page image, the method comprising:
accepting a camera image of a page; creating a filtered edge map and identifying text-likely regions; projecting the filtered edge map and text-likely regions into a polar coordinate system to determine page lines and warped image page curves; creating an adaptive two-dimensional (2D) ruled mesh piecewise planar approximation of a warped page surface; estimating a camera focal length; creating a three-dimensional (3D) model using the adaptive 2D ruled mesh and camera focal length estimate; and, using the 3D model, creating a 2D target mesh rectifying the image of the page.