System and Method for Scanned Document Correction
First Claim
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.
2 Assignments
0 Petitions
Accused Products
Abstract
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.
27 Citations
29 Claims
-
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. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
-
15. A computer-readable medium with processor executable instructions for correcting a warped page image, the instructions comprising the steps of:
-
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.
-
-
16. A system for the correction of a warped page image, the system comprising:
-
a non-transitory memory; a processor; an interface to accept a camera image of a page, and to supply a rectified image of the page; an image correction application stored in the memory and enabled as a sequence of processor executable steps for; 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. - View Dependent Claims (17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29)
-
Specification