Print Inspection Reference Images for Faster Job Matching

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional image inspection methods require time-consuming generation of reference images prior to each job, increasing processing time due to the need for rasterization and image conversion.

Innovation Solution

An inspection apparatus and method that efficiently generates reference images by preprocessing them independently of paper type and orientation, allowing for high-speed image matching by aligning and converting scanned images to a common RGB color space and performing geometric corrections, thus reducing the computational load.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If reference images are generated from image data inputted as a job prior to executing the job, then image quality inspection accuracy is improved, but processing time increases

Engineering Contradiction:
Improveimage quality inspection accuracyVSAvoidprocessing time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent applies preliminary action by generating reference images in advance during job preparation rather than during actual printing execution. The reference image generation is performed before the print job starts, allowing the actual printing process to focus only on executing the print commands without the overhead of reference image creation. This separates the reference image generation task from the print execution task, enabling faster processing during the actual printing operation while maintaining inspection accuracy through pre-generated reference images.

Inventive Principle:
Principle #10Preliminary action

2Measurement precision

If reference images are generated for each job, then inspection accuracy is maintained, but productivity decreases

Engineering Contradiction:
Improveinspection accuracyVSAvoidprocessing speed
Core Design Contradiction:
Measurement precisionVSProductivity

Solution Approach 1:

The patent implements preliminary action by preparing reference images before the print job executes. This allows the printing system to maintain high productivity during actual printing operations since the reference images are already ready for comparison. The reference image generation is performed as a preliminary step during job setup or in advance, eliminating the need to wait for reference image generation during the printing process itself.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent ensures continuity of useful action by maintaining a ready state for reference images that can be immediately used when print jobs are executed. The system keeps reference images available for continuous comparison during printing operations, eliminating idle waiting time and ensuring that the inspection process runs continuously without interruption for reference image generation.

Inventive Principle:
Principle #20Continuity of useful action

3Speed

If rasterization processing is performed on image data prior to job execution, then image matching speed is improved, but time required for processing increases

Engineering Contradiction:
Improveimage matching speedVSAvoidreference image generation time
Core Design Contradiction:
SpeedVSLoss of time

Solution Approach 1:

The patent applies preliminary action by performing rasterization processing in advance before the actual print job execution. The image data is converted to raster format and reference images are generated beforehand, so that when the print job executes, the system can directly use the pre-rasterized images for quick matching and inspection. This separates the time-consuming rasterization task from the time-sensitive print execution, allowing fast image matching during printing while bearing the time cost of rasterization during the preliminary preparation phase.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP4358504B1Inspection apparatus and method of controlling the same, and storage medium
Publication Date: 2025.08.13 CANON KK
  • EP4358504B1 patent drawingFigure 1
  • EP4358504B1 patent drawingFigure 2
  • EP4358504B1 patent drawingFigure 3

AI summary

The inspection apparatus (200) performs first image processing (S603, S604) on image data used in printing the image, and stores image data for which the first image processing has been performed as a reference image. The inspection apparatus determines whether a first reference image corresponding to a reference image that can be used in a job to be inspected is stored, and if it is determined that the corresponding first reference image is stored, performs second image processing (S607-S609) on the first reference image to convert the first reference image into a second reference image corresponding to the job. The inspection apparatus obtains a scanned image by reading an image of paper on which printing has been performed according to the job and performs processing (S610) for matching the obtained scanned image and the second reference image.