Laserfiche Clinic Liaison HMC, Sept. 12 th, 2006 Adam Field Stephen Smith Ben Tribelhorn, PM Aaron Wolin Advisor: Zach Dodds

The Problem To convert pictures of documents taken with a digital camera into images that can be organized using Laserfiche's OCR and database technologies. Project goal: raw imageOCR-able image

The Problem To convert pictures of documents taken with a digital camera into images that can be organized using Laserfiche's OCR and database technologies. Project goal: Some important cases: presence of paperclips and/or staples varied/confusing backgrounds (including stacks of papers) one or more edges off the edge of the image knowing when the system has failed camera perspective issues - documents not images head-on (?) other important cases? raw imageOCR-able image

Approach taken by previous clinic Finding document corners Unwarping to 8.5 x 11" Possible approach taken by current clinic First analyzing text-line boundaries Then unwarping to straighten them Approaches Outside - InInside - Out ?

Lu and Tan. “Camera Document Restoration for OCR.” VSBs Camera Document Restoration for OCR Several algorithms use VSBs to detect and correct the image Able to detect the type of distortion or severity of the warping Uses “Vertical Stroke Boundaries” VSBs of characters

Lu, Chen, and Ko. “Perspective rectification of document images using fuzzy set and morphological operations.” Tip point tracing process. Finding Vertical Stroke Boundaries Connected components first Find the "top" and "base" lines for a line of text Scan between the top and base lines, searching for pixels that form relatively orthogonal and straight lines

Avila and Lins. “A Fast Orientation and Skew Detection Algorithm for Monochromatic Document Images.” A Fast Orientation and Skew Detection Algorithm Uses connected components and nearest neighbors to find document skew Places the text line angles into two histograms from ±90º Precisions are 1.0º and 0.1º The skew angle is the histogram peak

Hand- writing Geometric PerspectiveSkew Magazines/ Newspaper Forms Problem Taxonomy Mostly text documents warp severity document difficulty

Hand- writing Geometric PerspectiveSkew Magazines/ Newspaper Forms Problem Priorities ? Mostly text documents primary focus secondary focus warp severity document difficulty

Pair 1's plan Finding character strokes Estimating warp severity Thresholding picture from ben and stephen

Least-sq. line-fitting Visualizing the processing Finding skew estimates Two-tier assessment 1) reasonable? 2) OCR accuracy picture from aaron & adam Pair 2's plan

Tentative Schedule Weekly conference calls with Ed Heaney Accessible codebase and performance updates Other deliverables ? Th 9/21 (11:30 am) Call - progress update T 9/26 Initial Harvey Mudd Th 9/28 Prototype of each algorithm F 10/6 ? Site visit and Laserfiche

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Other Papers

Hand Writing Image Warping GeometricPerspectiveSkew Magazin es Forms Plain Text

Hand- writing Geometric PerspectiveSkew Magazines/ Newspaper Forms Taxonomy Mostly text documents