Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Sub-pixel checkerboard corner detection method based on color constancy

A technology of color constancy and corner detection, applied in image enhancement, image analysis, image data processing, etc., to achieve good universal effect

Active Publication Date: 2018-05-08
SHANGHAI HUI X IMAGING INFORMATION TECH
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the position of the Harris corner detected in the first step will change with the change of surface illumination, and the sub-pixel precision corner point extracted by quadratic surface fitting in the second step will also be affected by the change of surface illumination

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Sub-pixel checkerboard corner detection method based on color constancy
  • Sub-pixel checkerboard corner detection method based on color constancy
  • Sub-pixel checkerboard corner detection method based on color constancy

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0043] In order to make the technical means, creative features, goals and effects achieved by the present invention easy to understand, the present invention will be further described below in conjunction with specific diagrams.

[0044] refer to figure 1 , a sub-pixel checkerboard corner detection method based on color constancy, comprising the following steps:

[0045] In the first step, the color space of the image is normalized by the following formula, so that the calibration plate image is invariant to the illumination and color shift:

[0046]

[0047] Among them, (R,G,B) represent the three color channels of the color image, (μ R ,μ G ,μ B ) represents the mean value of the three color channels in the image, (σ R ,σ G ,σ B ) represents the variance of the three color channels in the image.

[0048]It can be simply proved from the following process that the above normalization process can make the color histogram of the image have color constancy:

[0049] ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention belongs to the technical fields of image enhancement and feature detection and particularly relates to a camera calibration relevant technology in the three-dimensional measurement field. A sub-pixel checkerboard corner detection method based on color constancy comprises the steps that a, a Harris corner detector with color constancy is proposed; and b, the sub-pixel precision cornerdetection method with illumination and color offset invariance is proposed. By the adoption of the technical characteristics, almost identical pixel precision corner positions can be obtained relative to illumination and color changes.

Description

technical field [0001] The invention belongs to the technical field of image enhancement and feature detection, and specifically relates to the relevant technology of camera calibration in the field of three-dimensional measurement. Background technique [0002] The image enhancement and feature detection technology used for camera calibration is to overcome the influence of light intensity changes and large dynamic range in the image on the accuracy of the detected feature point position, so that camera calibration can adapt to complex lighting conditions, so it is very important. meaning. Color constancy is the constancy of color perception that simulates human vision, and refers to the characteristic that the human eye's perception of color remains unchanged when the illumination on the surface of an object changes. It can be seen that color constancy can overcome the influence of illumination changes on checkerboard corner detection. [0003] Based on the Beer-Lambert ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): G06T7/80G06T7/00G06T7/90
CPCG06T7/0002G06T7/80G06T7/90G06T2207/10004G06T2207/20164
Inventor 刘家朋
Owner SHANGHAI HUI X IMAGING INFORMATION TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com