Vein Extraction via Low-Frequency Component Separation

Solution Overview

Problem

Biometric authentication devices with general-purpose image pickup devices face challenges in extracting vein shapes due to demosaicking processes that reduce low-frequency components, leading to difficulties in extracting biological information from images.

Innovation Solution

An image processing apparatus that separates low-frequency components from input images, executes a demosaicking process, and merges the results with the separated components to enhance the extraction of vein shapes as biological information.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a demosaicking process is executed for an image including veins, then sampling noise is reduced, but low-frequency components are reduced leading to difficulty in extracting vein shapes

Engineering Contradiction:

Core Design Contradiction:

ReliabilityVSLoss of information

Solution Approach 1:

The patent segments the image processing into distinct stages: first separating low-frequency components from the demosaicked image, then merging them back in a controlled manner. This segmentation allows the demosaicking process to reduce sampling noise while preserving low-frequency components through the separation and selective merging mechanism.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent performs preliminary separation of low-frequency components before executing the demosaicking process. By pre-separating these components, the system can then apply demosaicking to reduce sampling noise while ensuring the low-frequency components are restored through the merging unit, preventing information loss.

Inventive Principle:

Principle #10Preliminary action

2Measurement precision

If a demosaicking process is executed to reduce sampling noise, then image quality improves, but vein shape extraction becomes difficult due to reduced low-frequency components

Engineering Contradiction:

Core Design Contradiction:

Measurement precisionVSDifficulty of detecting and measuring

Solution Approach 1:

The patent introduces low-frequency components as an intermediary element that mediates between the demosaicked image and the final output. The merging unit combines the demosaicked image (with reduced sampling noise) and the separated low-frequency components, enabling both improved image quality and effective vein shape extraction.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent merges the demosaicked image signal with the separated low-frequency components through a merging unit. This combination allows the system to benefit from both the sampling noise reduction achieved through demosaicking and the low-frequency information needed for vein shape extraction, resolving the contradiction between image quality and detection difficulty.

Inventive Principle:

Principle #5Merging (Combining)

Data Source

PatentUS10210601B2Image processing apparatus, image processing method, and computer-readable recording medium

Publication Date: 2019.02.19

AI summary

The image processing apparatus is configured by including a palm luminance estimation unit and a surface reflected component enhancement unit that separate low-frequency components from a signal indicating luminance values of pixels of an input image, a denoising processing unit that executes a denoising process for the signal from which the low-frequency components have been separated, and a merging unit that generates an image by merging the signal after the denoising process and the low-frequency components.