Angular point detection method based on visible light and infrared universal calibration board

Abstract

The invention discloses an angular point detection method based on a visible light and infrared universal calibration plate. The calibration plate is composed of a calibration plate bottom plate and two rectangular sheets made of different materials. The two sheets made of different materials comprise metal sheets and non-metal sheets, and the adjacent rectangular sheets are made of different materials; the two materials have different absorption degrees on visible light and infrared spectrum photons, so that the calibration plate is enabled to be clear in imaging under a visible light cameraand an infrared camera; an identifier is arranged on a checkerboard to mark the position of an initial unit grid, world coordinates of corners on a calibration board are determined, sub-pixel-level corner coordinates of four points of the initial unit grid are detected on a shot checkerboard image, and then the sub-pixel-level corner coordinates are diverged outwards through a homography matrix tofinally complete corner detection. The calibration plate is combined with an angular point detection method, so that the detection effect is more accurate and reliable.

Description

technical field [0001] The invention belongs to the technical field of camera calibration, and in particular relates to a corner point detection method based on a visible light and infrared universal calibration plate. Background technique [0002] Today, the combined use of visible light and infrared cameras has been widely used in military reconnaissance, autonomous driving, wildlife protection and other fields. The fusion of the image information captured by the visible light camera and the infrared camera can achieve complementary advantages and expand the use scenarios of the vision system. However, both visible light and infrared cameras need to be calibrated before use to obtain the corresponding internal and external parameters. Due to the difference in the sensing spectrum of the visible light camera and the infrared camera, the black and white checkerboard calibration board or the ordinary circular array calibration board cannot be clearly imaged under the infrare...

AI Technical Summary

Problems solved by technology

Due to the different sensing spectra of visible light cameras and infrared cameras, the black and white checkerboard calibration plate or ordinary circular array calibration plate cannot clearly image under the infrared camera, that is, the black and white checkerboard calibration plate cannot be used to calibrate the infrared camera

[0003] At present, the common infrared camera calibration boards are imaged by heating or cooling to create temperature differences. This kind of calibration board usually has the disadvantages of blurred corners, poor image contrast, and high production costs.

Not only that, when shooting the existing checkerboard calibration board, the checkerboard calibration board cannot cover the entire camera field of view, that is, the current corner detection algorithm can only detect the complete checkerboard image, so the checkerboard cannot be used Extract the feature points of the edge area, so the calibrated internal and external parameters of the camera must be inaccurate

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