Digital Master Document for OMR Error Correction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current optical mark recognition (OMR) and optical character recognition (OCR) processes face challenges due to image degradation and distortion caused by scanners and printers, leading to increased failure rates and errors in content extraction from scanned documents.

Innovation Solution

A digital master document is generated and stored, allowing for direct comparison with scanned marked documents, using field characteristic information and test patterns to correct for image quality issues and reduce errors, and applying filters to restore image quality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a scanned blank form document is used for comparison in OMR, then the document can be digitized and stored, but scanner image quality degradation causes blurring and distortion that lead to recognition errors

Engineering Contradiction:
Improverecognition accuracyVSAvoidimage quality
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The patent creates a digital master document template before scanning, which serves as the reference for comparison. This digital template is generated without scanner-induced degradation, and test patterns are pre-inserted into it. The digital master document is stored and used as the baseline for detecting marks on scanned forms, eliminating the need to scan a blank physical form.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent introduces test patterns as intermediary elements that are inserted into the digital master document. These test patterns serve as reference markers that allow the system to detect and correct scanner-induced distortions by comparing the positions and characteristics of test patterns in the scanned image against those in the digital master document.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Productivity

If advanced image processing algorithms are used to automate OMR, then content extraction can be performed, but the reliability of such processes becomes difficult to ensure due to scanner distortion

Engineering Contradiction:
Improvecontent extraction efficiencyVSAvoidrecognition reliability
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent implements a feedback mechanism where the system compares test patterns from the scanned image against the digital master document, detects distortions, and automatically corrects the scanned image or adjusts comparison parameters. This closed-loop feedback ensures that scanner-induced variations do not compromise recognition reliability while maintaining automated processing efficiency.

Inventive Principle:
Principle #23Feedback

3Reliability

If a digital master document is created and stored, then comparison with marked documents can be performed directly, but additional steps are required to create and store the digital template

Engineering Contradiction:
Improverecognition accuracyVSAvoidprocess complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The digital master document is created once and stored for repeated use. While this adds an initial setup step, it eliminates the need to scan blank forms for each processing task and provides consistent, high-quality reference data for all subsequent mark recognition operations, improving overall system reliability.

Inventive Principle:
Principle #10Preliminary action

4Reliability

If the entire digital master document is used for comparison, then comprehensive mark detection is possible, but processing time and computational resources increase

Engineering Contradiction:
Improvemark detection accuracyVSAvoidprocessing time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent divides the document into specific regions or fields of interest, and the comparison process focuses only on those segments where marks are expected to be located. This segmentation approach maintains comprehensive mark detection capability while significantly reducing processing time and computational resources by avoiding unnecessary comparison of entire document areas.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentUS7791756B2Methods for identifying marks using a digital master document and scanned image enhancement
Publication Date: 2010.09.07 LEXMARK INTERNATIONAL INC
  • US7791756B2 patent drawing
  • US7791756B2 patent drawing
  • US7791756B2 patent drawing

AI summary

To reduce errors introduced by a scanner, an unmarked, digital master document may be generated and stored in digital form so that subsequent scanning of the document is unnecessary to place it in digital form for comparison to a marked version of the document. Additionally, regions or fields, rather than the entire digital master document, may be individually created, stored, and subsequently used for comparison to corresponding portions of a marked version. Further, test targets or patterns may be inserted into the content of a digital master document. Characteristics of image quality degeneration and distortion can be extracted from printed versions of the test targets or patterns and used to effect closed loop control to digitally reduce image quality degeneration caused by the scanner.