Method for accurately calculating actual width of single pixel in crack image

An accurate calculation and crack width technology, applied in the field of crack images, can solve the problem of difficult to measure the distance between the camera and the bridge crack, and achieve the effect of eliminating uneven illumination, maintaining the original image size, and clear pictures

Inactive Publication Date: 2021-01-08
SHANDONG TRANSPORTATION INST
View PDF4 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Camera parameters need to be obtained accurately through experiments and calculations. When taking pictures of bridges on the spot, the distance between the camera and bridge cracks is often difficult to measure

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
  • Method for accurately calculating actual width of single pixel in crack image
  • Method for accurately calculating actual width of single pixel in crack image
  • Method for accurately calculating actual width of single pixel in crack image

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0035] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

[0036] The invention uses a standard block to calibrate the pixels in the image, the actual size of the standard block is known, it is placed next to the target crack, and then a camera is used to take pictures.

[0037] A method for accurately calculating the actual width of a single pixel in a crack image, specifically comprising the following steps:

[0038] (1) The multi-scale Retinex method is used to preprocess the captured pictures

[003...

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 discloses a method for accurately calculating the actual width of a single pixel in a crack image. The method specifically comprises the following steps: preprocessing a shot picture byadopting a multi-scale Retinex method; correcting the image by using perspective transformation; according to the actual length of a standard rectangular mark block and the pixel length occupied in the corrected image, obtaining the actual length a represented by each pixel, wherein the product of the calculated crack width pixel value and a is the actual crack width value. According to the method, the standard rectangle is obtained by preprocessing the picture and correcting the image, and the actual crack width value is calculated by indirectly establishing the proportional relation betweenthe image coordinate system and the actual coordinate system, so that the technical problem that the distance between the camera and the bridge crack is difficult to measure accurately is solved.

Description

technical field [0001] The invention relates to the technical field of crack images, in particular to a method for accurately calculating the actual width of a single pixel in a crack image. Background technique [0002] When using a digital camera as a collection device to take pictures of bridge cracks, it is necessary to calibrate the pixels of the camera. The corresponding relationship between the position of a certain point on the surface of the actual object and the point on the image needs to be determined by the parameters of the digital camera, the camera angle and the distance between the camera and the object. Camera parameters need to be obtained accurately through experiments and calculations. When taking pictures of bridges on the spot, the distance between the camera and bridge cracks is often difficult to measure. Contents of the invention [0003] In order to solve the technical problem that the distance between a camera and a bridge crack is difficult to...

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): G06T7/136G06T7/155G06T7/194G06T7/62
CPCG06T7/136G06T7/155G06T7/62G06T7/194
Inventor 魏帅帅郭庆辉牛磊周广利李鹏程刘福忠李广奇赵宁
Owner SHANDONG TRANSPORTATION INST
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap